Background The COVID-19 pandemic hit all over the world and cancer patients are more vulnerable for COVID-19. Mortality rate may increase up to 25% in solid malignancies. In parallel to increased mortality rates among cancer patients, safety concerns regarding cancer treatment has increased over time. However, there were contradictory results for the cancer treatment during pandemic. In this study, we assessed the effect of cancer treatment on the severity of COVID-19. Methods The MEDLINE database was searched on September 01, 2020. Primary endpoints were severe disease and death in the cancer patients treated within the last 30 days before COVID-19 diagnosis. Quality of included studies were assessed by New Castle-Ottawa Scale. Generic inverse variance method was used to calculate odds ratios (ORs) for each outcome. Results Sixteen studies were included for this meta-analysis. Chemotherapy within the last thirty days before COVID-19 diagnosis increased the risk of death in cancer patients after adjusting for confounding variables (OR: 1.85; 95% CI:1.26-2.71). However, severe COVID-19 risk did not increase. Furthermore, targeted therapies, immunotherapy, surgery, and radiotherapy did not increase the severe disease and death risk in cancer patients with COVID-19. Conclusion Chemotherapy increased the risk of death from COVID-19 in cancer patients. However, there was no safety concern for immunotherapy, targeted therapies, surgery, and radiotherapy.

Background: The ABO blood groups and Rh factor may affect the risk of lung cancer. Materials and Methods: We analyzed 2,044 lung cancer patients with serologically confirmed ABO/Rh blood group. A group of 3,022,883 healthy blood donors of Turkish Red Crescent was identified as a control group. We compared the distributions of ABO/Rh blood group between them. Results: The median age was 62 years (range: 17-90). There was a clear male predominance (84% vs. 16%). Overall distributions of ABO blood groups were significantly different between patients and controls (p=0.01). There were also significant differences between patients and controls with respect to Rh positive vs. Rh negative (p=0.04) and O vs. non-O (p=0.002). There were no statistically significant differences of blood groups with respect to sex, age, or histology. Conclusions: In the study population, ABO blood types were associated with the lung cancer. Having non-O blood type and Rh-negative feature increased the risk of lung cancer. However, further prospective studies are necessary to define the mechanisms by which ABO blood type may influence the lung cancer risk.

Background: Previous studies have observed an association between ABO blood group and risk for certain gastrointestinal malignancies, including pancreatic and gastric cancer. However, it is unclear whether there is such an association with colorectal cancer (CRC). In this study, possible relationships between ABO blood groups and Rh factor and KRAS status in patients with CRC were investigated. Materials and Methods: In 1,620 patients with CRC, blood group and Rh factor were examined and compared with the control group of 3,022,883 healthy volunteer blood donors of the Turkish Red Crescent between 2004 and 2011. The relationship of blood groups with wild type K-ras status was also evaluated. Results: Overall distributions of ABO blood groups as well as Rh factor were comparable between patients (45% A, 7.2% AB, 16.4% B, 31.4% O, and 87.2% Rh+) and controls (42.2% A, 7.6% AB, 16.3% B, 33.9% O, and 87.7% Rh+) (p=0.099). However, there were statistically significant difference between patients and controls with respect to O vs. non O blood group (p=0.033) and marginally significant difference for A vs. non-A blood group (p=0.052). Among patients, the median age was 62 (range 17-97), 58.1% were male. There were no statistically significant differences respect to sex and K-ras status. Conclusion: In present study, the ABO/Rh blood groups were statistically significantly associated with the risk of CRC. There were no relationship between K-ras status and ABO blood group and Rh factor. However further studies with larger numbers of patients are needed to establish the role of blood groups and to define the mechanisms by which ABO blood type affect CRC.

Our study aimed to assess inequities in the clinical trial participation for the selected patient groups. We searched the Food and Drug Administration (FDA) database and extracted phase‐III clinical trial data from MEDLINE for each approved drug by the FDA between January 1, 2006, and June 30, 2020. We analyzed the inclusion/exclusion criteria, participation according to gender, ethnic group, performance score, the positivity of HBV and HCV, and HIV, having comorbidities and brain metastasis. We compared the findings with that of the general population by retrieving data from the Surveillance, Epidemiology and End Results (SEER) database. We identified 142 phase III pivotal oncology trials that enrolled 105 397 patients. The proportion of female patients in trials was lower than their relative prevalence in the general population from SEER region (36% vs 49.6%, P < .001). The rates of black patients included were lower than their relative prevalence from SEER region (2.1% vs 9.8%, P < .001). 1.3% and 0.8% of patients had HBV and HCV infections, respectively. The patients' numbers with organ dysfunction were not established due to insufficient data from clinical trials. 1.6% of all patients had controlled brain metastasis. Black patients, women and patients with brain metastasis or with HBV and HCV were underrepresented. Our study underscores the importance of expanding the inclusion/exclusion criteria of pivotal oncology trials to be more representative of patients seen in clinical practice.

It is well established that adjuvant treatment reduces mortality after early breast cancer. However, the optimal timing of adjuvant treatment is not well described. To determine the optimal timing of adjuvant treatment, 402 breast cancer patients who received adjuvant treatment at Ankara Oncology Research and Training Hospital between January 1995 and August 2002 were evaluated retrospectively. Three hundred and fifty-seven (88.8%) patients received adjuvant chemotherapy, 204 (50.7%) of these patients received only adjuvant chemotherapy and 153 (38%) patients received tamoxifen following chemotherapy. Remaining 45 (11.2%) patients received only adjuvant tamoxifen. The median time to start adjuvant treatment after surgery was day 21 (range, days 4 to days 258), and the median follow-up was 50 months (range, 6-105 months). The patients were divided into 5 groups according to starting time of chemotherapy (shorter than 14 days, between days 15-29, between days 30-44, between days 45.-59 and more than 59 days). Overall survival (OS) and disease-free survival (DFS) were not shown significantly different between for 5 groups (P>0.05). Secondly, patients were divided into two groups as starting adjuvant treatment equal to or shorter than 44 days and longer than 44 days (n=344, 85.6% and vs. n=58, 14.4%, respectively). OS was significantly better in patients who started to receive adjuvant treatment within 44 days after surgery compared to patients who received adjuvant treatment after 44 days (92 vs. 83.3%, P=0.03) for 5 years, but DFS was not significantly different between two groups (83.4 vs. 82.2%, P>0.05). According to our study, adjuvant treatment of breast cancer should be initiated earlier after surgery.