Background: Prostate cancer is a common malignancy among men worldwide, with various histopathologic features that influence its progression and prognosis. One such feature is perineural invasion (PNI), which has been associated with aggressive disease. In this retrospective study, we analyzed genomic alterations associated with PNI in patients who underwent radical prostatectomy. Methods: A total of 421 prostate cancer patients who underwent radical prostatectomy without neoadjuvant therapy were identified from The Cancer Genome Atlas. PNI was present in 378 patients (89.8%) and absent in 43 (10.2%). Differentially expressed genes were identified, and mRNA expression levels of key genes were analyzed. The prognostic significance of these genes was evaluated using log-rank tests and Cox proportional hazards models to estimate hazard ratios and 95% confidence intervals. Results: Levels of COL9A3, ASPN, ESR1, MUC1, PIP, SFRP4, KRT19, CLDN1, and COMP were significantly higher in the tumor tissues of patients in the PNI group compared to those in the non-PNI group (q < 0.05), and RYR2, MME, and AZGP1 expression levels were significantly higher in the non-PNI group (q < 0.05). A high mRNA expression level of AZGP1 was associated with longer disease-free survival, whereas high mRNA expressions of ASPN, COMP, RYR2, and SFRP4 were associated with shorter disease-free survival. Conclusions: Prostate cancer patients with genomic alterations associated with PNI may face a higher risk of disease progression after prostatectomy, highlighting the need for further prospective studies to validate these findings.

Small cell lung cancer (SCLC) is an aggressive malignancy with a high incidence of brain metastases. Prophylactic cranial irradiation (PCI) was developed to reduce central nervous system (CNS) relapses and has been shown to improve survival, particularly in limited-stage disease. The pivotal Auperin meta-analysis and subsequent studies confirmed its role in patients achieving a complete response to initial therapy. In extensive-stage SCLC, earlier trials demonstrated reduced brain metastases and modest survival gains, but more recent studies incorporating routine magnetic resonance imaging (MRI) surveillance failed to show overall survival benefits, supporting MRI monitoring with salvage therapy as an alternative. Neurocognitive toxicity remains the major limitation of PCI, especially in older adults. Common effects include memory impairment, cognitive changes, and a reduced quality of life. Advances such as hippocampal avoidance PCI and neuroprotective strategies like memantine have shown the ability to mitigate long-term decline. Modern radiotherapy techniques, including intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), enable the precise sparing of critical structures while maintaining intracranial control. The integration of immunotherapy has shifted treatment paradigms in SCLC. While checkpoint inhibitors have improved systemic outcomes, their impact on brain relapses and interactions with PCI remain uncertain. This review provides an overview of the evolution of PCI in SCLC, while emphasizing current challenges and future directions.

Background and purpose: In preparation for adjuvant breast radiation therapy (RT), permanent skin tattoo marks are often placed on the patient's skin to assist patient positioning on the treatment couch. However, those marks are often undesirable, in particular, for breast cancer patients due to various cosmetic and psychological concerns and other drawbacks. With surface‐guided radiation therapy (SGRT) being readily available, it becomes possible to adopt a “tattoo‐free” approach for patient setup. This study evaluates the efficacy and dosimetric implications of a tattoo‐free setup technique. Methods: Thirty right‐sided breast cancer patients were included in this retrospective study. All patients received an initial course of whole breast treatment of 42.56 Gy in 16 fractions using a tangential 3D conformal technique, followed by a 10 Gy boost to the lumpectomy site in four fractions. SGRT was used in daily setup to reproduce patient's positioning between the simulation and treatment. The patient's breast surface was aligned with the corresponding reference breast surface generated from the planning computed tomography (CT) images via AlignRT system. To evaluate the feasibility and accuracy of the new tattoo‐free approach, at the beginning of the program and for this group of patients, daily orthogonal kV imaging pair was performed to confirm the treatment positioning by verifying the bony landmarks, and the translational couch shifts were recorded for every fraction. Those shifts were applied to the isocenter positions of the original corresponding clinical treatment plans, and dose distributions were re‐computed. The dosimetric evaluation between the two setup methods, that is, the breast surface alignment versus the bony landmark alignment, were then assessed on the original clinical plan. New plan sums were obtained from the 16 fractions, where each one was recalculated based on the new isocenter positions determined with the kV imaging shifts. Boost fractions were excluded in this study, as setup was verified using surgical clips as the matching reference. Results: Translational shifts for the 30 patients ( N = 480) were reviewed. The mean absolute shift resulted from the orthogonal kV imaging‐based setup following the SGRT setup, in lateral, vertical and longitudinal directions, were 0.20 cm (ranged from 0 to 1.98 cm with 95% confidence interval (CI) of 0.18–0.22 cm), 0.23 cm (ranged from 0–1.25 cm with 95% CI of 0.21–0.25 cm), and 0.22 cm (ranged from 0 to 1.35 cm with 95% CI of 0.19–0.24 cm), respectively. The average change in V95% coverage over the treatment course of the 30 patients was 0.99%. No significant differences in V20Gy of lung (%) and mean heart dose were observed between the original and the corresponding shifted plans. Conclusion: A SGRT based tattoo‐free setup approach was clinically evaluated and compared to a kV orthogonal imaging‐based approach for whole breast RT treatment. It was found that the tattoo‐free setup approach is acceptable in treatment setup accuracy and dosimetric coverage. Caution needs to be paid to patient movement during setup and treatment to ensure the safety and efficacy of the approach.