Purpose: Umbilical metastasis, known as Sister Mary Joseph's nodule (SMJN), is a manifestation of advanced malignant disease. Patients with SMJN usually require supportive care or palliative systemic chemotherapy. However, with the increasing number of older and infirm patients, radiation therapy for SMJN is needed more frequently. Therefore, we conducted this review to provide insights into radiation treatment for this rare condition. Methods and Materials: We searched PubMed on October 16, 2022, and obtained 275 articles that described SMJN or metastatic tumors within or near the umbilicus, as well as 255 case reports or case series (298 patients) and 20 reviews, original articles, or other study types, 1 of which also described a case. Results: The prognosis of patients with SMJN is extremely poor. However, some patients can survive for more than 2 years. The primary organs of the umbilical metastasis are mainly in the gastrointestinal tract, including the stomach, colon, and pancreas. In addition to these organs, the ovaries, uterine corpus, and breasts are the major organs affected in women. Metastasis may be divided into 4 types according to the tumor location and mechanism of the extension: within the umbilicus, not within although existing near or adjacent to the umbilicus, in the umbilical or paraumbilical hernia sac, and iatrogenic disease. Only 7 reports described patients who received radiation therapy in detail. The patients were divided into 2 groups: a relatively long course and high total dose (approximately 45 Gy) group, and a short course and low total dose group. Conclusions: Umbilical metastasis, known as SMJN, is a rare disease and is divided into 4 types based on the location of the disease and extent mechanism. Although the prognosis of the disease is poor, some patients survive for more than 2 years. Only 7 case reports precisely described radiation therapy. Half of the patients were treated with a short course, whereas the other half were treated with (c) 2023 The Authors. Published by Elsevier Inc. on behalf of American Society for Radiation Oncology. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Purpose To determine the efficacy and safety of target volume determination by 18 F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) for intensity-modulated radiation therapy (IMRT) for locally advanced head and neck squamous cell carcinoma (HNSCC) extending into the oral cavity or oropharynx. Methods We prospectively treated 10 consecutive consenting patients with HNSCC using IMRT, with target volumes determined by PET-CT. Gross tumor volume (GTV) and clinical target volume (CTV) at the oral level were determined by two radiation oncologists for CT, magnetic resonance imaging (MRI), and PET-CT. Differences in target volume (GTV PET , GTV CT , GTV MRI , CTV PET , CTV CT , and CTV MRI ) for each modality and the interobserver variability of the target volume were evaluated using the Dice similarity coefficient and Hausdorff distance. Clinical outcomes, including acute adverse events (AEs) and local control were evaluated. Results The mean GTV was smallest for GTV PET , followed by GTV CT and GTV MRI . There was a significant difference between GTV PET and GTV MRI , but not between the other two groups. The interobserver variability of target volume with PET-CT was significantly less than that with CT or MRI for GTV and tended to be less for CTV, but there was no significant difference in CTV between the modalities. Grade ≤ 3 acute dermatitis, mucositis, and dysphagia occurred in 55%, 88%, and 22% of patients, respectively, but no grade 4 AEs were observed. There was no local recurrence at the oral level after a median follow-up period of 37 months (range, 15–55 months). Conclusions The results suggest that the target volume determined by PET-CT could safely reduce GTV size and interobserver variability in patients with locally advanced HNSCC extending into the oral cavity or oropharynx undergoing IMRT. Trial registration UMIN, UMIN000033007. Registered 16 jun 2018, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000037631

BACKGROUND/AIM:Malignant lymphoma (ML) including Hodgkin's lymphoma and non-Hodgkin's lymphoma is often treated with local radiation therapy (RT) in combination with autologous hematopoietic stem cell transplantation (ASCT) to prevent relapse; however, the efficacy and optimal timing of this approach is unclear. In this study, a national survey conducted by the Japanese Radiation Oncology Study Group reviewed ML cases from 2011 to 2019 to determine whether RT should be added to ASCT, focusing on the use of autologous peripheral blood stem cell transplantation (auto-PBSCT), a predominant form of ASCT. PATIENTS AND METHODS:The survey encompassed 92 patients from 11 institutes, and assessed histological ML types, treatment regimens, timing of RT relative to auto-PBSCT, and associated adverse events. RESULTS:The results indicated no significant differences in adverse events, including myelosuppression, based on the timing of RT in relation to auto-PBSCT. However, anemia was more prevalent when RT was administered before auto-PBSCT, and there was a higher incidence of neutropenia recovery delay in patients receiving RT after auto-PBSCT. CONCLUSION:This study provides valuable insights into the variable practices of auto-PBSCT and local RT in ML treatment, emphasizing the need for optimized timing of these therapies to improve patient outcomes and reduce complications.

We conducted a prospective study to quantitatively evaluate the movement of the chest wall to establish the simple and reproducible deep-inspiration breath-hold (DIBH) method. The left nipple position was monitored to confirm the inspiratory state. Planning computed tomography (CT) was performed under DIBH and free-breath. We conducted radiation plans with DIBH and free-breath CT and evaluated organ at risk (OAR) and target doses according to two different plans. The relationship between positioning errors of the chest wall and patient factors was evaluated using univariate analysis and fixed-effects models. Twenty-three patients aged <= 60 years were enrolled during January-August 2021; 358 daily radiation treatments were evaluated. The median time of treatment room occupancy was 16 minutes (interquartile range, 14-20). The area of the planning target volume (PTV) surrounded by the 95% isodose line was more extensive in DIBH than in free breathing (71.6% vs 69.5%, P < 0.01), whereas the cardiac and left anterior descending (LAD) artery doses were lower (both P < 0.01). In the fixed-effects model analysis, the occupation time of the treatment room was correlated with positioning error. The difference between the planned and irradiated dose was the largest in the LAD branch of the coronary artery (-2.5 Gy), although the OAR dose decreased owing to positional error. The current DIBH method, wherein a single point on the chest wall is monitored to confirm that the patient is in an inspiratory state, allows radiation to be performed in a short time with a small dose error.

Objective:Intensity-modulated radiotherapy (IMRT) is a well-established radiotherapy technique for delivering radiation to cancer with high conformity while sparing the surrounding normal tissue. Two main purposes of this study are: (1) to investigate dose calculation accuracy of helical IMRT (HIMRT) and volumetric-modulated arc therapy (VMAT) on surface region and (2) to evaluate the dosimetric efficacy of HIMRT and VMAT for scalp-sparing in whole brain radiotherapy (WBRT).Methods:First, using a radiochromic film and water-equivalent phantom with three types of boluses (1, 3, 5 mm), calculation/measurement dose agreement at the surface region in the VMAT and HIMRT plans were examined. Then, HIMRT, 6MV-VMAT and 10MV-VMAT with scalp-sparing, and two conventional three-dimensional conformal radiotherapy plans (6MV-3DCRT and 10MV-3DCRT; as reference data) were created for 30 patients with brain metastasis (30 Gy/10 fractions). The mean dose to the scalp and the scalp volume receiving 24 and 30 Gy were compared.Results:The percentage dose differences between the calculation and measurement were within 7%, except for the HIMRT plan at a depth of 1 mm. The averaged mean scalp doses [Gy], V24Gy [%], and V30Gy [%] (1SD) for 6MV-3DCRT, 10MV-3DCRT, HIMRT, 6MV-VMAT, and 10MV-VMAT were [26.6 (1.1), 86.4 (7.3), 13.2 (4.2)], [25.4 (1.0), 77.8 (7.5), 13.2 (4.2)], [23.2 (1.5), 42.8 (19.2), 0.2 (0.5)], [23.6 (1.6), 47.5 (17.9), 1.2 (1.8)], and [22.7 (1.7), 36.4 (17.6), 0.7 (1.1)], respectively.Conclusion:Regarding the dose parameters, HIMRT achieved a lower scalp dose compared with 6MV-VMAT. However, the highest ability to reduce the mean scalp dose was showed in 10MV-VMAT.Advances in knowledge:Scalp-sparing WBRT using HIMRT or VMAT may prevent radiation-induced alopecia in patients with BM.

The appropriate dosage of edaravone-a radioprotective agent-and its effect on tumors are unknown. This study evaluated the effects of edaravone on intestinal injuries and tumors in mice induced by whole body X-ray irradiation. Small intestinal mucositis was induced in C3H/HeNSlc mice using a single X-ray dose (15 Gy). Edaravone (15, 30, and 100 mg/kg) was administered 30 min before irradiation to evaluate its protective effect. After 3.5 days, the jejunum was removed and the histological changes were evaluated. Next, C3H/HeNSlc mice with squamous cell carcinoma VII tumors were provided the same single X-ray dose and 100 mg/kg edaravone; further, the tumors were immediately induced after irradiation. The tumor cell viability was detected using an in vivo-in vitro colony formation assay. We found that the intestinal colony-forming ability after irradiation was significantly higher in the 100 mg/kg edaravone group than that in the control group. Moreover, the apoptotic cells in the villi immunohistochemically stained with cleaved caspase-3 were significantly lower in the 100 mg/kg edaravone group than in the control group. We found no radioprotective effects of intraperitoneally inoculated edaravone in both hind legs on squamous cell carcinoma VII tumors. These findings suggest that 100 mg/kg edaravone exerts protective effects on small intestinal injuries without interfering with the antitumor effects of radiation.

The pathophysiological mechanisms underlying olfactory dysfunction are not well known but can be triggered in neurodegenerative diseases and after viral infection.1Xydakis MS Albers MW Holbrook EH et al.Post-viral effects of COVID-19 in the olfactory system and their implications.Lancet Neurol. 2021; 20: 753-761Summary Full Text Full Text PDF PubMed Scopus (31) Google Scholar We report a patient whose case could provide interesting insights into the neurophysiology of smell. A woman aged 35 years was referred in July, 2019, to the Department of Radiation Oncology for radiotherapy of residual tumour tissue located in the olfactory region. Full details of the patient's medical history are in the appendix (pp 1–4). The patient had previously undergone two surgical procedures to resect olfactory neuroblastoma. The first operation was a frontal craniotomy done 1 year before referral (July, 2018). After this surgical procedure had been performed, the patient reported that she had lost all olfaction, although this loss of sensation was not confirmed objectively. The second operation was done 1 year after the first operation (July, 2019) and entailed transnasal resection of recurrent tumour tissue. At the time of this second surgery, the patient had not recovered any olfaction. The olfactory epithelium was resected completely during these two operations, and the tumour could not be detected on CT 3 months after the second surgery (appendix p 5) or at the 21-month follow-up (appendix p 6). 21 days after the second surgery, we treated the patient with helical tomotherapy, a type of intensity-modulated radiotherapy, administered as 60 Gy in 30 fractions over 43 days. A dosimetric analysis is presented in the appendix (p 7). During radiotherapy sessions, the patient complained of a foul odour. Olfaction was reported when the x-rays were directed through the frontal lobe and the lower part of the nasal cavity outside the olfactory epithelial level (figure). During radiotherapy sessions to treat brain tumours, other patients have also reported experiencing foul smells.2Hara N Isobe A Yamada K et al.Unusual visual and olfactory perceptions during radiotherapy sessions: an investigation of the organs responsible.J Radiat Res (Tokyo). 2021; 62: 718-725Crossref PubMed Scopus (3) Google Scholar, 3Obinata M Yamada K Sasai K Unusual olfactory perception during radiation sessions for primary brain tumors: a retrospective study.J Radiat Res (Tokyo). 2019; 60: 812-817Crossref PubMed Scopus (4) Google Scholar We did a prospective study in which 13 (34%) of 38 patients who received radiotherapy for brain or near-orbital tumours reported olfactory perceptions.2Hara N Isobe A Yamada K et al.Unusual visual and olfactory perceptions during radiotherapy sessions: an investigation of the organs responsible.J Radiat Res (Tokyo). 2021; 62: 718-725Crossref PubMed Scopus (3) Google Scholar Two (5%) of the 38 patients had no olfactory epithelium, including the individual described here. The cause or causes of these reported olfactory sensations remain undetermined. Patients might have either smelled substances such as ozone generated by the radiation or they might have had phantosmia.4Yang JC Khakoo Y Lightner DD Wolden SL Phantosmia during radiation therapy: a report of 2 cases.J Child Neurol. 2013; 28: 791-794Crossref PubMed Scopus (13) Google Scholar Moreover, temporal lobe seizures have been associated with a reported foul odour, such as that of burning tyres.5Berkowitz AL Cranial nerves 1, 9, 10, 11, and 12.in: Berkowitz AL Clinical neurology and neuroanatomy: a localization-based approach. McGraw-Hill, New York2017: 125-128Google Scholar It is possible that terminal sensors of cranial nerves, such as the trigeminal nerve, can detect the smell of substances generated by radiation. However, the patient we report here perceived an odour when the x-ray passed through the frontal lobe. Therefore, it could be concluded that the CNS of the patient detected the x-rays during radiation sessions, although this hypothesis remains to be proven. KS reports a grant from Hitachi. All other authors declare no competing interests. Download .pdf (.44 MB) Help with pdf files Supplementary appendix Post-viral effects of COVID-19 in the olfactory system and their implicationsThe mechanisms by which any upper respiratory virus, including SARS-CoV-2, impairs chemosensory function are not known. COVID-19 is frequently associated with olfactory dysfunction after viral infection, which provides a research opportunity to evaluate the natural course of this neurological finding. Clinical trials and prospective and histological studies of new-onset post-viral olfactory dysfunction have been limited by small sample sizes and a paucity of advanced neuroimaging data and neuropathological samples. Full-Text PDF

BackgroundDefinitive radiotherapy (RT) for stage I esophageal cancer was reported to result in noninferior overall survival (OS) compared with surgery. However, only a few detailed reports of recurrence patterns and subsequent salvage treatments have been published. This study aimed to compare recurrence patterns and subsequent salvage treatments after definitive RT or chemoradiotherapy (CRT) between cT1a and cT1bN0M0 esophageal cancer (EC).MethodsPatients with cT1a or cT1bN0M0 esophageal squamous cell carcinoma who received definitive RT or CRT were included. Survival outcomes, recurrence patterns, and salvage treatments were evaluated.ResultsIn total, 40 patients with EC receiving RT or CRT were divided into two groups for evaluation: cT1a (20 patients) and cT1b (20 patients) groups. The 3-year OS rates were 83% and 65% (p = 0.06) and the 3-year progression-free survival rates were 68% and 44% (p = 0.15) in the cT1a and cT1b groups, respectively. Among those in the cT1a group, six had local recurrence and two had metachronous recurrence. Seven patients underwent salvage endoscopic submucosal dissection and one patient received argon plasma coagulation treatment. Among those in the cT1b group, six had local recurrence, one had regional recurrence, and one had both. Of these, one underwent salvage endoscopic submucosal dissection, one received photodynamic therapy, three underwent surgery, one received RT, and two received the best supportive care. Compared with the cT1b group, the cT1a group had a higher proportion of patients who underwent endoscopic treatments (p = 0.007). After the endoscopic treatments, no recurrences were observed in both groups.ConclusionsRegional recurrence and distant metastasis were not observed in the cT1a group. A higher proportion of patients in the cT1a group received salvage endoscopic treatments, and their OS tended to be favorable.

Background:Studies on the clinical outcomes of radiotherapy for clinical (c)T1aN0M0 (UICC-TNM Classification, Eighth Edition) esophageal cancer (EC) are limited. Therefore, this retrospective study aimed to clarify the clinical outcomes of definitive radiotherapy (RT) or chemoradiotherapy (CRT) for cT1aN0M0 EC unsuitable for endoscopic resection and surgery.Methods:Patients with cT1aN0M0 esophageal squamous cell carcinoma who underwent definitive RT or CRT between January 2009 and December 2020 were retrospectively reviewed. The initial response, toxicities, survival rates, recurrence patterns, and salvage treatments of the patients were evaluated. Initial response was measured using the Response Evaluation Criteria in Solid Tumors guideline. Toxicity was assessed and documented following the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Survival rates from the date of initiation of treatment were measured using the Kaplan-Meier method.Results:Twenty patients treated with definitive RT or CRT were included in the study. The median follow-up duration was 55 months (range, 13-131 months). All patients achieved complete response to the initial treatment. Grade 3 acute toxicities observed esophagitis (10%), pneumonitis (5%), and leukopenia (5%). Late toxicities higher than grade 3 were not observed. The 1-, 3-, and 5-year overall and disease-specific survival rates were 100% and 100%, 83% and 100%, and 67% and 100%, respectively. No treatment-related deaths occurred. Among the 20 patients, 6 showed local recurrence and 2 showed metachronous recurrence. Seven patients underwent salvage endoscopic submucosal dissection (ESD), and one underwent argon plasma coagulation treatment. After the endoscopic treatment, no recurrences were observed.Conclusions:Definitive RT or CRT was considered an alternative initial treatment for patients with cT1aN0M0 EC who were unsuitable for endoscopic resection and surgery.

Objectives:To develop a method for detecting jaw positions during jaw-tracking delivery to ensure an accurate delivery of radiation to patients using an electronic portal imaging device (EPID) in the cine mode on a linear accelerator for radiotherapy. Materials:A bidirectional picket fence (BPF) plan was used in a novel application to detect jaw positions during jaw-tracking delivery. In the BPF plan, jaws tracked multileaf collimator (MLC) apertures. The irradiated patterns were acquired by an EPID in the cine mode. Methods:The upper- and lower-half leaves in the MLC moved in opposite directions to facilitate detection of jaw positions on EPID images. A picket-fence-like image was created by summing all acquired cine images and evaluated to detect MLC leaf positions. Results:Jaw positions determined on the cine images were compared with those expected from the delivered BPF plan. The absolute differences (average ± 1 standard deviation) were 0.16 ± 0.19 mm for the X1 jaw and 0.11 ± 0.16 mm for the X2 jaw. The maximum error in the MLC leaf positions detected in the picket-fence-like pattern were 0.11 mm. Conclusions:Jaw positions during jaw-tracking delivery were identified using the cine EPID images and could be determined within an accuracy better than 0.5 mm. The BPF plan is also available as a picket fence test and can determine the MLC leaf positions to an accuracy better than 0.5 mm.

CyberKnife radiotherapy enables tumor-tracking irradiation using positional information regarding the tumor and a fiducial marker in a patient's body. This positional information acts as a surrogate of tumor motion. Therefore, deviations in these movements should be quantitatively estimated and included as an internal margin for radiation treatment planning. This study aimed to investigate variations between the positions of fiducial markers and tumor regions using 320-row area detector computed tomography and to analyze the effectiveness of our proposed method in contouring tumor regions based on the fiducial marker position. To determine the moving tumor volume, a typical single-phase image was selected, and pixel values in other phase images were accumulated. Moreover, a maximum-intensity projection image was created to clarify motion deviations in the tumor volume. To evaluate the delineation accuracy, the dice similarity coefficient and mean distance to agreement were calculated in phase-selected and breath-holding computed tomography. Moving chest phantom images were acquired using helical scanning 4-dimensional computed tomography (H-4DCT) and volumetric scanning 4-dimensional computed tomography (V-4DCT), and the delineation accuracies were compared for each scanning type. The average dice similarity coefficient and mean distance to agreement were degraded in limited-phase images, which cannot represent the hysteretic motion of a tumor. Moreover, deviations in tumor volume with unstable motion reached 71.6% in H-4DCT but only 1.6% in V-4DCT. Our proposed method with V-4DCT using area detector computed tomography can achieve accurate moving tumor delineation and can clarify positional associations between the fiducial marker and tumor under respiratory motion.

Objectives:In radiation therapy, the field-in-field (FIF) technique is used to prevent the administration of unnecessarily high doses to reduce toxicity. Recently, the FIF technique has been used for whole brain irradiation (WBI). Using the FIF technique, the volume that receives a higher than prescribed dose (hotspot) can be largely reduced; however, the treatment planning requires time. Therefore, to reduce the burden on the treatment planners, we propose a semiautomatic treatment planning method for the FIF technique. Methods:In the semiautomatic FIF technique, hotspot regions in a treatment plan without the FIF technique are identified three-dimensionally, and beams with blocks that cover the hotspot regions using a multileaf collimator (sub-beams) are automatically created. The sub-beams are added to the original plan, and weights are assigned based on the maximum dose of the original plan to decrease the doses in the hotspot regions. This method was applied to 22 patients previously treated with WBI, wherein treatment plans were originally created without the FIF technique. Results:In the semiautomatic FIF plans, the hotspots almost disappeared. The dose to 95% of the volume and the volume receiving at least 95% of the prescribed dose in the planning target volume decreased by only 0.3% ± 0.2% and 0.0% ± 0.1%, respectively, on average compared with those in the original plan. The average semiautomatic FIF processing time was 28 ± 4 s. Conclusions:The proposed method reduced the hotspot regions with a slight change in the target coverage.

Purpose: We investigated the localization accuracy of the off-isocenter targets using SyncTraX FX4, a new image registration device. Methods: In a phantom study, we used a MultiMet-WL Cube with metal targets at different distances from the isocenter. Image registrations were performed with SyncTraX and cone-beam computed tomography (CBCT). Nineteen fields with different gantry, collimator, and couch angles were delivered to each target. Localization errors of the off-isocenter targets were then evaluated. In a clinical study, localization accuracy was evaluated for 32 patients. First, image registration was performed using SyncTraX, and the accuracy of patient positioning was evaluated using CBCT. Next, positioning corrections were performed for intracranial setup errors exceeding the threshold (0.5 mm/0.5) in each field. Finally, total setup uncertainty was evaluated using CBCT. Differences in dosimetric errors from planned doses between no patient positioning corrections during treatment and positioning corrections with SyncTraX were also evaluated. Results: In the phantom study, the positioning accuracy on targets up to 7 cm from the isocenter was within 1 mm. In the clinical practice, the localization accuracies of SyncTraX were 0.35 +/- 0.39 mm, 0.30 +/- 0.24 mm, and 0.03 +/- 0.27 mm in the lateral, vertical, and longitudinal directions, respectively. Post-treatment setup errors were reduced by correcting intrafractional setup errors with SyncTraX during treatment. Positioning corrections with SyncTraX reduced the maximum dosimetric error from 1.6% to 1.0%. Conclusions: SyncTraX provides satisfactory localization accuracy for the off-isocenter targets within 7 cm. SyncTraX reduce dosimetric errors caused by intrafractional setup errors during treatment.

In the present review, I provide an overview of the development of radiation therapy and short history of the Department of Radiation Oncology, Juntendo University. I also emphasize the importance of radiation therapy as a major treatment modality for cancers. Radiation therapy is a standard treatment for malignant tumors. It aims to deliver a sufficient radiation dose to a target volume to eradicate tumor cells or relieve symptoms of disease. Therapy can achieve good results in many types of cancers. Although radiation therapy sometimes causes undesirable adverse events, it is generally less invasive than other treatment modalities and does not alter the shape and function of healthy organs. When the author joined this field in 1981, radiation therapy techniques were highly primitive; however, during the past 42 years, treatment has advanced rapidly with the development of computer science, mechanical techniques and instrumentation. Currently, patients can be treated with precise radiation techniques, including intensity-modulated radiation therapy, image-guided radiation therapy, stereotactic irradiation, and brachytherapy. We also introduced a new treatment planning system that uses not only anatomical but also metabolic imaging, which permits correct delineation of the target volume. Therefore, it is crucial to stay up to date with advances and developments in rapidly emerging technologies to maintain high-quality treatment. The Department of Radiation Oncology at Juntendo University (Tokyo, Japan) is still small; however, it is gradually expanding and conducting research in both clinical and basic fields. It is the author's hope that many young investigators will join this field in the future.

Purpose: During radiation therapy sessions, certain patients may perceive smells, particularly in younger populations. The sense of smell generally does not interrupt treatment; hence, it has attracted limited attention from oncologists worldwide. However, in certain cases, the prevention of smell perception may be necessary when treating pediatric patients. In this regard, this study reviewed previous studies pertaining to this unusual phenomenon of smell perception during radiation sessions. Methods and Materials: A PubMed search using the terms “radi*” AND (“olfaction” OR “odor” OR “smell” OR “phantosmia”) was performed, and 9 articles related to this sensation were identified. Furthermore, through the references in these 9 articles, 3 additional related studies were identified. Results: Perception of smell during radiation treatment sessions was first reported in 1989. This phenomenon entails the perception of a pungent, repulsive, and unpleasant smell and is generally only observed in the presence of radiation beams. Occasionally, these smell perceptions are also accompanied by visual and gustatory sensations. Patients complain about this sensation more frequently when their olfactory regions are irradiated. Nevertheless, some patients have also reported experiencing this sensation when these areas are not included in the radiation field. Although the intensity of this sensation is low, intervention is required to prevent it. The cause of this perception remains unclear and requires further investigation. Conclusions: Conclusions: During radiotherapy sessions, certain patients may perceive smells. The cause of this perception remains unclear and requires further investigation.

This study aims to implement three-dimensional convolutional neural networks (3D-CNN) for clinical target volume (CTV) segmentation for whole breast irradiation and investigate the focus of 3D-CNNs during decision-making using gradient-weighted class activation mapping (Grad-CAM). A 3D-UNet CNN was adopted to conduct automatic segmentation of the CTV for breast cancer. The 3D-UNet was trained using three datasets of left-, right-, and both left- and right-sided breast cancer patients. Segmentation accuracy was evaluated using the Dice similarity coefficient (DSC). Grad-CAM was applied to trained CNNs. The DSCs for the datasets of the left-, right-, and both left- and right-sided breasts were on an average 0.88, 0.89, and 0.85, respectively. The Grad-CAM heatmaps showed that the 3D-UNet used for segmentation determined the CTV region from the target-side breast tissue and by referring to the opposite-side breast. Although the size of the dataset was limited, DSC ≥ 0.85 was achieved for the segmentation of breast CTV using the 3D-UNet. Grad-CAM indicates the applicable scope and limitations of using a CNN by indicating the focus of such networks during decision-making.

PurposeThis is a report of our initial experience using computed tomography (CT)-guided interstitial high dose rate (HDR) brachytherapy to treat bulky pelvic nodal metastases as a part of definitive radiotherapy.Material and methodsBetween February 2015 and April 2019, 14 cervical/endometrial cancer patients presenting with bulky pelvic node(s) underwent nodal interstitial brachytherapy boost in our institution. In total, 17 nodes were treated. The median maximum diameters of the positive nodes at the time of diagnosis and at the first nodal implant were 25 mm (range: 10–65 mm) and 16 mm (range: 9–51 mm), respectively. Dosimetry data of the lymph nodal target volume and small bowel were collected and compared using the paired-sample t-test. Treatment-related toxicities were classified using the Common Terminology Criteria for Adverse Events version 4.0.ResultsThe median follow-up time for all patients was 26 months. Local recurrence in pelvic nodes occurred in one patient (7%) after 16 months. One patient experienced grade 3 bladder bleeding, and one patient experienced grade 2 pubic bone fracture. No patient had grade 2 or greater gastrointestinal toxicity. In the dosimetric analysis, the mean nodal brachytherapy D90% in terms of the total equivalent dose of 2 Gy (EQD2) was 65.6 Gyαβ10. The mean small bowel dose (SBD)0.1cc and SBD1cc in terms of the total EQD2 were 60.4 and 56.5 Gyαβ3, respectively. Nodal D90% was significantly higher in terms of the total EQD2 than the SBD0.1cc (p = 0.003) and SBD1cc (p < 0.001). The Kaplan-Meier 2-year pelvic control estimate was 90%.ConclusionsCT-guided interstitial HDR pelvic nodal brachytherapy appears to be well tolerated with excellent local control in cervical or endometrial cancer patients with bulky pelvic nodes. This approach may offer a useful therapeutic option for unresected bulky pelvic nodes.

We retrospectively analyzed the frequency of retropharyngeal lymph node （Rp） metastasis on diagnostic images and the irradiation dose to the same area in 55 patients with advanced maxillary sinus squamous cell carcinoma who underwent external radiotherapy and superselective intra-arterial chemotherapy at Juntendo Hospital. Reassessment of pretreatment images revealed potential Rp metastases in 10 patients （18％）; 9 who were diagnosed with a minor axis of ≥ 5 mm and 1 diagnosed with a major axis of ≥ 10 mm. Patients who underwent MRI or PET-CT tended to have a high rate of Rp node metastases （P ＝ 0.090）. The median irradiation dose for Rp metastasis was 57.7 Gy, and 8/10 patients were irradiated with high doses without targeting. As a result, no recurrence of Rp metastasis was observed. When the Rp region is not targeted during intensity-modulated radiation therapy, the Rp region dose is significantly lower than that of three-dimensional radiation therapy （47.4 Gy vs. 36.0 Gy, respectively; p ＝ 0.040）.

Background: The aim of this study was to evaluate the long-term treatment results of combined superselective intraarterial chemotherapy and radiation therapy for advanced maxillary sinus cancer (MSC) and the incidence of regional lymph node failure, and to reveal the clinical and anatomical predictive factors for metastasis. Methods: We retrospectively evaluated 55 consecutive patients with locally advanced squamous cell carcinoma of the maxillary sinus who were treated with external radiotherapy and superselective intraarterial chemotherapy. Elective nodal irradiation (ENI) was performed only in the clinical node-positive (cN+) cases and not in the clinical node-negative (cN0) cases. Results: Thirty-eight patients were cN0, and 17 were cN+ at diagnosis. Regional lymph node metastases occurred in 7 of 38 patients with cN0, and 2 of 17 with cN+ during the median follow-up period of 36 months. There were more cases of high-grade (3 or 4) late adverse events in the ENI group than in the non-ENI group (13% vs. 41%, respectively; p = 0.03). In cN0 cases without ENI, invasion of the pterygoid plates (57% vs. 90%; p < 0.01) and oral cavity (35% vs. 92%, with invasion vs without invasion, respectively; p = 0.02) was significantly correlated with a low 5-year regional recurrence-free rate. Conclusions: Patients with MCS and invasion of the pterygoid plates and oral cavity can be considered appropriate candidates for ENI.

Abstract Background The optimal chest wall bolus regimen for postmastectomy radiotherapy (PMRT) remains unknown. We aimed to prospectively evaluate the use of a 1-mm-thick daily tissue-equivalent bolus in patients who received PMRT using thermoluminescent dosimeters (TLDs) and skin toxicity assessment. Methods Patients with a 1-mm-thick daily bolus during PMRT were prospectively enrolled at The Juntendo University Hospital. The surface dose was measured in vivo under the 1-mm-thick bolus on the chest wall. We assessed the acute skin toxicity weekly during PMRT, and 1, 2, 4, and 12 weeks after the completion of PMRT. Results A total of 19 patients aged 32–79 years old received PMRT from July 2019 to January 2020. All patients completed the protocol treatment without interruptions, and the median follow-up was 32 weeks. In vivo dosimetry analysis revealed surface doses between 77 and 113% of the prescribed dose, with a mean of 92% of the prescribed radiation dose, and a standard deviation of 7% being delivered. Grade 2 dermatitis was found in 10 patients (53%), and Grade 3 dermatitis was found in one patient (5%). All cases of Grade 2 and 3 dermatitis were improved 4 weeks after PMRT. There were no cases of Grade 4 dermatitis and no chest wall recurrences during the treatment or follow-up period. Conclusions Results confirmed the feasibility of using a 1-mm-thick daily bolus for PMRT, exhibiting an appropriate dose buildup and acceptable skin toxicity without treatment interruptions. Trial registration The University Hospital Medical Information Network Clinical Trials Registry, UMIN000035773 . Registered 1 July 2019.