Patients with cancer are at an increased risk of developing coronavirus disease 2019 (COVID-19) infection. Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate (ADC) against epidermal growth factor receptor 2 (HER2)-positive cancer, known to cause drug-induced interstitial lung disease (DILD), including drug-induced pneumonitis. A 60-year-old woman with breast cancer developed a fever during treatment with T-DXd and was diagnosed with COVID-19. The fever persisted for approximately 3 weeks, and chest computed tomography showed multiple consolidations with bilateral peripheral predominance. Since the clinical course was atypical for COVID-19 due to the long duration of the fever and the CT pattern was frequently seen in T-DXd-induced ILD, the patient was diagnosed with T-DXd-induced ILD, following which, prednisolone was started, leading to improvement in the symptoms and fading of shadows. Even in patients suspected of COVID-19 pneumonia, physicians should consider the possibility of DILD, particularly in patients undergoing cancer treatment.

Background/Aim: Cyclin-dependent kinase (CDK) 4/6 inhibitors have become the standard of care as the first- and second-line treatments for hormone receptor-positive (HR+) or human epidermal growth factor receptor 2 (HER2)-negative metastatic and recurrent breast cancers. Although CDK 4/6 inhibitors can markedly prolong progression-free survival, there is no clear evidence of their post-treatment effects. The option of developing mammalian target of rapamycin (mTOR) inhibitors, such as everolimus, has been discussed as a post-treatment option for such patients. This study aimed at determining everolimus' efficacy as a post-treatment option following CDK4/6 inhibitor administration in clinical settings. Patients and Methods: Thirteen patients who received everolimus as a post-treatment after CDK4/6 inhibitor therapy from December 2017 to July 2021 were retrospectively reviewed. The primary endpoint was progression-free survival; the secondary endpoints were overall response rate, clinical benefit rate, and overall survival. Results: The median patient age, progression-free survival, and overall survival were 59 years (range=44-76 years), 9.1 months (95% confidence interval=2.3 to not reached), and 37.4 months (95% confidence interval=12.3-37.4), respectively. The overall response rate and clinical benefit rate were 15.3% (2/13) and 46.2% (6/13), respectively. Conclusion: Considering there is a mechanism of resistance to CDK4/6 inhibitors, everolimus would be important as an effective post-treatment for HR+ or HER2-negative metastatic and recurrent breast cancers treated with CDK4/6 inhibitors in clinical settings.

Background Previous large trials of trastuzumab (TZM) demonstrated improved outcomes in patients with HER2-positive early breast cancer. However, its effectiveness and safety in Japanese patients is not yet clear. Recently, new anti-HER2 agents were developed to improve treatment outcomes, but the patient selection criteria remain controversial. Purpose The aim of this study was to evaluate the long-term effectiveness of TZM therapy as perioperative therapy for HER2-positive operable breast cancer in daily clinical practice and to create a recurrence prediction model for therapeutic selection. Methods An observational study was conducted in Japan (UMIN000002737) to observe the prognosis of women ( n = 2024) with HER2-positive invasive breast cancer who received TZM for stage I–III C disease between July 2009 and June 2011. Moreover, a recurrence-predicting model was designed to evaluate the risk factors for recurrence. Results The 5- and 10-year disease-free survival (DFS) rates were 88.9 (95% CI 87.5–90.3%) and 82.4% (95% CI 79.2–85.6%), respectively. The 5- and 10-year overall survival (OS) rates were 96% (95% CI 95.1–96.9%) and 92.7% (95% CI 91.1–94.3%), respectively. Multivariate analysis revealed that the risk factors for recurrence were an age of ≥ 70 years, T2 or larger tumors, clinically detected lymph node metastasis, histological tumor diameter of > 1 cm, histologically detected lymph node metastasis (≥ n2), and the implementation of preoperative treatment. The 5-year recurrence rate under the standard treatment was estimated to be > 10% in patients with a score of 3 or greater on the recurrence-predicting model. Conclusion The recurrence-predicting model designed in this study may improve treatment selection of patients with stage I–III C disease. However, further studies are needed to validate the scores generated by this model.

Background: There are little data on the usefulness of trastuzumab (TZM) retreatment as the first-line treatment for patients with HER2 (human epidermal growth factor receptor 2)–positive breast cancer recurrence after perioperative treatment with TZM. Aim: To clarify the outcome and safety of TZM retreatment in patients with recurrent HER2-positive breast cancer. Method: An observational study was conducted on patients who relapsed after primary systemic therapy with TZM using the central registration system. The primary end point was progression-free survival (PFS). Secondary end points consisted of the response rate, overall survival (OS), and safety. Result: In total, 34 patients were registered between July 2009 and June 2012. The median follow-up time was 23.7 months (2-24 months). The 1- and 2-year PFS rates were 46.9% (95% confidence interval (95% CI): 29.2%-62.9%) and 29.8% (95% CI: 15.0%-46.3%), respectively (median 10.6 months). The median PFS time for patients receiving TZM combined with CTx was 13.9 months. The 1-and 2-year OR rates were 93.9 (95% CI: 77.9%-98.4%) and 84.8% (95% CI: 67.4%-93.4%). Trastuzumab-induced grade 3/4 adverse events were not observed. Conclusions: This study suggests that the PFS and OS in Japanese patients who relapsed after perioperative TZM therapy improved or were similar to those in previous reports. Differences in patient backgrounds and treatments must be considered when interpreting the results. Trastuzumab should be used combination with CTx and/or HTx for retreatment. Retreatment with TZM is safe. Trial registration: UMIN000002738.

Massive gastrointestinal bleeding from gastrointestinal varices is one of the most serious complications in patients with portal hypertension. However, if no bleeding point can be detected by endoscopy in the predilection sites of gastrointestinal varices, such as the esophagus and stomach, ectopic gastrointestinal variceal bleeding should be considered as a differential diagnosis. Herein, we report a case of ectopic ileal variceal bleeding in a 57-year-old woman, which was successfully diagnosed by multi-detector row CT (MDCT) and angiography and treated by segmental ileum resection. To date, there have been no consensus for the treatment of ectopic ileal variceal bleeding. This review was designed to clarify the clinical characteristics of patients with ectopic ileal variceal and discuss possible treatment strategies. From the PubMed database and our own database, we reviewed 21 consecutive cases of ileal variceal bleeding diagnosed from 1982 to 2017. MDCT and angiography is useful for the rapid examination and surgical resection of an affected lesion and is a safe and effective treatment strategy to avoid further bleeding.

This study compared the clinical utility of indocyanine green (ICG) fluorescence and radioisotope (RI) for sentinel lymph node (SLN) detection in breast cancer.

Previous large trials with trastuzumab (TZM) showed improved outcome in patients with HER2-positive early-stage breast cancer. However, the efficacy and safety of TZM in Japanese patients have not been fully evaluated. We have therefore conducted an observational study in Japan.

1091 Background: Near-infrared fluorescence signal of indocyanien green (ICG) can visualize subcutaneous lymphatic flows and draining (sentinel) lymph nodes (SLNs). In fluorescence ICG Breast Study Group 01 study (fICG BR01), this ICG fluorescence mapping was superior to the dye method in early stage breast cancer (Sugie T, et al. Ann Surg Oncol 2013). The following fICG BR02 study evaluates clinical usefulness of this ICG fluorescence method in comparison to the conventional radioisotope (RI) method. Methods: On the day before or on the day of SLN biopsy, 99mTc-labelled colloid was injected into the subareolar region of each patient. Before the start of operation, ICG was injected into the subareolar region and lymphatic flows bound for the axilla were traced with PDE camera (Hamamatsu Photonics Co, Japan). A real-time navigation surgery by ICG florescence imaging enabled to identify SLNs to be excised. A gamma probe was used to verify no residual radioactivity in the axilla after SLN removal. Results: A total of 847 women with T1-2 breast cancer were enrolled and 821 pts. were included in the per-protocol final analysis. The median pts. age was 55 (range, 22-80) years and the median BMI was 22.1 (range, 14.9-38.8) kg/m2. There was no significant difference in the detection rate between the ICG and RI method (97.2% vs 97.0%). However, a combination of ICG and RI achieved a significant higher detection rate than RI alone (99.8% vs 97%, p<0.001). The involvement of SLNs was found in 180 pts. and a detection rate of positive SLN using ICG fluorescence and RI was 93.3% and 90%, respectively. The detection rate of SLNs with a combination of ICG and RI was improved significantly compared with RI alone (97% vs 90%, p<0.001). There is no serious adverse event due to hypersensitivity to ICG. Conclusions: The ICG fluorescence method has a high detection rate of SLN comparable with that of the RI method. A combination of these two methods yield a significant improvement of SLN detection compared with RI alone. The results of this study confirm that ICG fluorescence imaging system is an alternative and/or additive to the conventional SLN mapping using a radioactive tracer in breast cancer. Clinical trial information: UMIN000005167.

A case of esophageal duplication is described. A 63-year-old woman was admitted to the hospital because of a chest pain. Surgery was performed under a diagnosis of ratro mediastinal abscess formation caused by a perforation of esophageal diverticulum. Pathologic review of the specithmen revealed that the cyst wall which was diagnosed as the abscess wall before the operation included an ectopic pancreatic tissue and smooth muscle layer. The pathologic diagnosis of esophageal duplication was made. In a review of the Japanese literature, there has been no report that esophageal duplications include ectopic pancreatic tissue.