A BSTRACT Objectives: To assess the real-world outcomes of postoperative radiotherapy (PORT) for oral cavity squamous cell carcinoma and to examine whether delay in starting PORT affects the survival. Methods: We retrospectively reviewed 47 consecutive patients who underwent curative surgery followed by PORT. Radiotherapy was delivered using standard planning procedures, with 66 Gy in 33 fractions for high-risk patients and 60 Gy in 30 fractions for low-risk patients. Time from surgery to PORT initiation was evaluated both continuously and as ≤6 weeks versus >6 weeks. Overall survival (OS) and progression-free survival (PFS) were measured from the start of radiotherapy and analyzed using the Kaplan–Meier methods and multivariable Cox regression. Results: The median interval from surgery to PORT was 6.1 weeks (range, 2.7–9.1). With a median follow-up of 19.4 months, the 2-year OS and PFS rates were 62.3% and 39.1%, respectively. Two-year OS was 77.8% in the ≤6-week group versus 49.0% in the >6-week group ( P = 0.045). Two-year PFS was 52.2% versus 26.1%, respectively ( P = 0.062). In multivariable analysis, PORT initiation >6 weeks after surgery was independently associated with worse PFS (hazard ratio 2.865, 95% confidence interval: 1.065–7.709; P = 0.037). Conclusion: In this real-world cohort, delayed initiation of PORT beyond 6 weeks after surgery was associated with inferior outcomes, including significantly worse PFS. Optimizing postoperative treatment timelines may improve the outcomes in oral cavity squamous cell carcinoma.
A BSTRACT Posterior reversible encephalopathy syndrome (PRES) is an uncommon but potentially serious neurotoxic complication characterized by acute neurological symptoms and characteristic radiological findings. Although it is classically associated with hypertension, renal failure, and immunosuppressive therapy, PRES has also been reported in association with cytotoxic chemotherapy, including gemcitabine. Gemcitabine-associated PRES remains rare, particularly in normotensive patients and in the presence of concurrent central nervous system malignancy. We report the case of a 39-year-old woman with metastatic HPV-positive cervical squamous cell carcinoma who developed acute neurological deterioration after receiving gemcitabine and carboplatin. She presented with severe headache, visual disturbances, nausea, vomiting, and papilledema without sustained severe hypertension. Initial brain computed tomography was unremarkable, while subsequent magnetic resonance imaging demonstrated bilateral cortical and subcortical T2/fluid-attenuated inversion recovery hyperintensities with areas of diffusion restriction, consistent with complicated PRES. Cerebrospinal fluid analysis was unremarkable. Despite aggressive neurocritical care management and discontinuation of chemotherapy, her condition deteriorated rapidly and was complicated by cerebral edema and uncal herniation. Neurosurgical intervention was considered non-beneficial in the setting of advanced malignancy. This case highlights gemcitabine as a possible precipitating factor for PRES even in normotensive patients and underscores the diagnostic complexity when PRES coexists with advanced cancer and central nervous system involvement. Although PRES is often described as reversible, outcomes may be poor in such patients. Early recognition, prompt neuroimaging, withdrawal of the offending agent, and multidisciplinary management remain essential to optimize outcomes.
A BSTRACT Synchronous adenocarcinomas of the rectum and prostate are rare, especially in the absence of an underlying genetic predisposition. Their anatomical proximity and differing therapeutic protocols pose a sequencing dilemma, as prioritization of one malignancy may delay the optimal management of the other and increase the risk of disease progression or treatment-related toxicity. A 79-year-old male presented with frequent loose stools mixed with blood and mucus. Positron emission tomography–computed tomography demonstrated distinct fluorodeoxyglucose-avid lesions in the rectum (maximum standardized uptake value [SUV max ]: 15.6) and prostate (SUV max : 23.19). Colonoscopic biopsy confirmed moderately differentiated rectal adenocarcinoma. Serum prostate-specific antigen was elevated at 56.35 ng/mL, and prostate biopsy confirmed acinar adenocarcinoma. To address sequencing challenges, androgen deprivation therapy (ADT) was initiated for prostate cancer, followed by abdominoperineal resection with end colostomy for rectal cancer. Definitive prostate radiotherapy and adjuvant rectal radiotherapy were delivered concurrently using intensity-modulated radiotherapy (IMRT) to prevent field overlap and dosimetric errors. Adjuvant chemotherapy for rectal cancer was subsequently administered, alongside continued ADT. At 1-year follow-up, the patient remained disease-free. This case demonstrates that synchronous rectal and prostate adenocarcinomas can be effectively managed through careful diagnostic confirmation and individualized treatment sequencing. The use of modern radiation techniques, such as concurrent IMRT, allows safe and precise dose delivery to both pelvic sites, enabling timely multimodality treatment when minimizing toxicity. Early multidisciplinary planning is essential for achieving favorable outcomes in such complex clinical scenarios.
A BSTRACT Purpose: Iso-center placement is a key determinant of dosimetric accuracy and workflow efficiency in intensity-modulated radiotherapy (IMRT). While the anatomical iso-center (AIP) is conventionally used, high-volume centers increasingly consider the virtual iso-center (VIP) defined during CT simulation to streamline patient setup. This study evaluates the dosimetric impact and workflow benefits of VIP relative to AIP in IMRT planning. Materials and Methods: A retrospective planning analysis was performed for 40 IMRT patients. For each case, two plans were generated: one centered on the AIP and the other on the VIP. Dosimetric indices, including conformity index (CI), homogeneity index (HI), target coverage, organ-at-risk (OAR) doses, monitor units (MUs), and iso-center displacement were compared. Workflow efficiency was assessed by estimating setup time saved through omission of couch shifts. Results: VIP-based plans demonstrated a statistically significant increase in MUs (mean + 4.4%, P < 0.001), strongly correlated with iso-center displacement ( r = 0.82). CI, HI, and OAR doses showed no significant differences between AIP and VIP plans ( P > 0.15). The VIP approach eliminated couch shifts, reducing average setup time by approximately 4.2 min per patient, translating into the potential to treat 5–6 additional patients per month. Larger displacements (>6 cm) were associated with greater MU penalties. Conclusions: VIP planning enhances workflow efficiency without compromising target coverage or OAR sparing. However, the consistent MU increase, particularly with large displacements, supports selective use and vigilant quality assurance.
