The effectiveness of radiotherapy in preventing disease recurrence after breast cancer surgery.

BACKGROUND AND OBJECTIVES: The locoregional management of breast cancer has a critical impact on prognosis. This study aimed to analyze the effectiveness of radiotherapy against the deleterious effect of positive surgical margins on disease outcomes. METHODS: Retrospective, single-center study enrolled 721 breast cancer patients with a median follow-up of approximately 64.50 months (3.67-247.40). Analyses were performed considering the end of adjuvant therapy, except endocrine therapy. Kaplan-Meier and Cox regression were performed to obtain the predictive value of treatments. RESULTS: The minimally adequate radiotherapy (≥45 cGy) was associated with improved outcomes in breast cancer patients compared to inadequate radiotherapy (<45 cGy/no) by controlling locoregional relapses and distant metastasis. In patients with positive surgical margins (n = 53), radiotherapy was associated with an approximate decrease of 90% in locoregional relapse risk [adjusted HR: 0.108 (0.012-0.932), p = 0.043]. Radiotherapy did not alter the adverse effect of positive surgical margins, especially in patients with a higher risk of poorly differentiated tumors (n = 146), presence of lymphovascular invasion (n = 163), and triple-negative subtype (n = 113). Notwithstanding, radiotherapy was associated with respective decreases of distant metastasis risk of 75.2% [adjusted HR: 0.248 (0.081-0.762), p = 0.015] and 67.8% [adjusted HR: 0.322 (0.101-1.029), p = 0.056] in patients with triple-negative tumors or with lymphovascular invasion. CONCLUSION: Adequate radiotherapy is associated with better outcomes in breast cancer. Despite improving locoregional relapse-free survival, radiotherapy does not ablate positive surgical margins, a factor of poorer prognosis that prevails mainly in patients with factors of higher relapse risk.

Impact of androgen deprivation therapy on mortality of prostate cancer patients with COVID-19: a propensity score-based analysis.

BACKGROUND: Previous studies hypothesized that androgen deprivation therapy (ADT) may reduce severe acute respiratory syndrome coronavirus 2 (SARS-COV2) infectivity. However, it is unknown whether there is an association between ADT and a higher survival in prostate cancer patients with COVID-19. METHODS: We performed a retrospective analysis of prostate cancer (PC) patients hospitalized to treat COVID-19 in Brazil's public health system. We compared patients with the active use of ADT versus those with non-active ADT, past use. We constructed propensity score models of patients in active versus non-active use of ADT. All variables were used to derive propensity score estimation in both models. In the first model we performed a pair-matched propensity score model between those under active and non-active use of ADT. To the second model we initially performed a multivariate backward elimination process to select variables to a final inverse-weight adjusted with double robust estimation model. RESULTS: We analyzed 199 PC patients with COVID-19 that received ADT. In total, 52.3% (95/199) of our patients were less than 75 years old, 78.4% (156/199) were on active ADT, and most were using a GnRH analog (80.1%; 125/156). Most of patients were in palliative treatment (89.9%; 179/199). Also, 63.3% of our cohort died from COVID-19. Forty-eight patients under active ADT were pair matched against 48 controls (non-active ADT). All patients (199) were analyzed in the double robust model. ADT active use were not protective factor in both inverse-weight based propensity score (OR 0.70, 95% CI 0.38-1.31, P = 0.263), and pair-matched propensity score (OR 0.67, 95% CI 0.27-1.63, P = 0.374) models. We noticed a significant imbalance in the propensity score of patients in active and those in non-active ADT, with important reductions in the differences after the adjustments. CONCLUSIONS: The active use of ADT was not associated with a reduced risk of death in patients with COVID-19.

Outcomes of COVID-19 Patients under Cytotoxic Cancer Chemotherapy in Brazil.

BACKGROUND: Cancer patients present a distinct vulnerability to COVID-19. It is unclear if chemotherapy could accentuate the overall risk in these patients. METHODS: We performed a retrospective analysis linking COVID-19 data and oncological information systems to compare lethality in patients undergoing cytotoxic chemotherapy before COVID-19. We considered patients who received chemotherapy in the last 30 days as in "active treatment", and patients who did not receive drugs in this period as "non-active treatment" for propensity-score pair matching. We also tested the influence of baseline variables in our results in a multivariate model. RESULTS: 66.1% (162/246) of patients in matched active chemotherapy died vs. 70.2% (172/246) in the matched non-active chemotherapy group. The risk of death was positively associated with palliative intent of treatment and hematologic neoplasms. Being in active chemotherapy was not associated with increased mortality compared to non-active treatment. We also noted in exploratory propensity-score matchings that the use of alkylating agents (odds ratio [OR] 0.38, 95% confidence interval [CI], 0.21-0.70) and topoisomerase II inhibitors (OR 0.28, 95% CI 0.14-0.56) were protective factors. CONCLUSIONS: This study does not demonstrate an increase in mortality for cancer patients under active cytotoxic chemotherapy with COVID-19.

Chemoradiotherapy With or Without Surgery for Esophageal Squamous Cancer According to Hospital Volume.

PURPOSE: Esophageal squamous cell cancer (ESCC) is still associated with a dismal prognosis. However, surgical series have shown that high-volume hospitals have better outcomes and that the impact of center volume on definitive chemoradiotherapy (dCRT) or CRT plus surgery (CRT + S) remains unknown. METHODS: We performed a retrospective analysis of patients with locally advanced stage II-III (non-T4) ESCC treated with dCRT or CRT + S in São Paulo state, Brazil. Descriptive variables were assessed with the χ2 test after categorization of hospital volume (high-volume [HV] center, top 5 higher volume, or low-volume [LV] center). Overall survival (OS) was assessed with Kaplan-Meier curves, log-rank tests, and Cox proportional hazards. Finally, an interaction test between each facility's treatments was performed. RESULTS: Between 2000 and 2013, 1,347 patients were analyzed (77% treated with dCRT and 65.7% in HV centers) with a median follow-up of 23.7 months. The median OS for dCRT was 14.1 months (95% CI, 13.3 to 15.3 months) and for CRT + S, 20.6 months (95% CI, 16.1 to 24.9 months). In the multivariable analysis, dCRT was associated with worse OS (hazard ratio [HR], 1.38; 95% CI, 1.19 to 1.61; P < .001) compared with CRT + S. HV hospitals were associated with better OS (HR, 0.82; 95% CI, 0.71 to 0.94; P = .004) compared with LV hospitals. Importantly, CRT + S superiority was restricted to HV hospitals (dCRT v CRT + S: HR, 1.56; 95% CI, 1.29 to 1.89; P < .001), while in LV hospitals, there was no statistically significant difference (HR, 1.23; 95% CI, 0.88 to 1.43; P = .350), with a significant interaction test (Pinteraction = .035). CONCLUSION: Our data show that CRT + S is superior to dCRT in the treatment of ESCC exclusively in HV hospitals, which favors the literature trend to centralize the treatment of ESCC in HV centers.