Gastric cancer is one of the most common malignancies worldwide. During the last 50 years, the histological classification of gastric carcinoma has been largely based on Lauren's criteria, in which gastric cancer is classified into two major histological subtypes, namely intestinal type and diffuse type adenocarcinoma. This classification was introduced in 1965, and remains currently widely accepted and employed, since it constitutes a simple and robust classification approach. The two histological subtypes of gastric cancer proposed by the Lauren classification exhibit a number of distinct clinical and molecular characteristics, including histogenesis, cell differentiation, epidemiology, etiology, carcinogenesis, biological behaviors and prognosis. Gastric cancer exhibits varied sensitivity to chemotherapy drugs and significant heterogeneity; therefore, the disease may be a target for individualized therapy. The Lauren classification may provide the basis for individualized treatment for advanced gastric cancer, which is increasingly gaining attention in the scientific field. However, few studies have investigated individualized treatment that is guided by pathological classification. The aim of the current review is to analyze the two major histological subtypes of gastric cancer, as proposed by the Lauren classification, and to discuss the implications of this for personalized chemotherapy.

Mismatch repair (MMR) gene is closely related to the pathogenesis of colon cancer. This study aimed to evaluate the association between MMR status and efficacy of irinotecan-based chemotherapy. As a target of 5-FU, thymidylate synthase (TS) expression level might be influenced by irinotecan. Understanding whether this influence of TS is related with MMR status is helpful to the further exploration of the mechanism of irinotecan sensitivity in metastatic colon cancer with different MMR status. One hundred eighty-four patients with metastatic colon cancer receiving irinotecan-based chemotherapy for the first-line treatment were included. Correlations between MMR and clinicopathological characteristics and prognosis were determined. Two pairs of colon cancer cell lines (HCT-116-hMLH1(Vector) (deficient MMR, dMMR) versus HCT-116-hMLH1(+) (proficient MMR, pMMR); SW480-shRNA-hMLH1 (dMMR) versus SW480-shRNA-Control (pMMR)) were established by regulating MMR status. Sensitivity of these cell lines to irinotecan was determined by MTT assay. Regulation of TS by irinotecan was evaluated by western blotting and quantitative real-time PCR assay. dMMR accounted for 18.5 % and was related with proximal colon cancer (p = 0.005), poorly differentiated tumors (p = 0.018) and favorable efficacy with a higher disease control rate (DCR), a longer progression-free survival (PFS) and a trend of longer overall survival (OS). dMMR colon cancer cells were more sensitive to irinotecan. TS expression level was reduced more in dMMR cells after irinotecan treatment (p < 0.05). Our study favors an increased sensitivity of irinotecan in colon cancer with dMMR status. MMR status may be a predictive biomarker of response to irinotecan-based chemotherapy in metastatic colon cancer.

Cancer patients are susceptible groups to COVID-19, and risk-adjusted models show that most cancer patients have a 25-39% mortality risk if infected with COVID-19. The infection rate of SARS-CoV-2 in cancer patients in China was 0.79% (12 of 1524 patients; 95% CI, 0.31.2%). The case fatality rate of COVID-19 in the overall population ranges from 2.3 to 8.0%; among these, the case fatality rate for cancer patients is at 5.6%. In a retrospective cohort study of 28 COVID-19-infected cancer patients, a total of 15 (53.6%) patients had severe outcomes with a mortality rate of 28.6%. In a pooled analysis by Aakash et al, a 2% cancer prevalence was found among admitted patients with COVID-19. In Italy, a report shows that among the 3200 patients who died of SARS-CoV-2, 19.4% were patients with cancer. In New York, 61 (28%) cancer patients succumbed to COVID-19 with a case fatality rate of 37% (20/54) and 25% (41/164) for hematologic and solid malignancies, respectively. Impacts of COVID-19 in cancer care include interruptions of life-saving therapies, distraction effects, and diagnostic overshadowing that involve diverting attention to the pandemic rather than to cancer patients and disruptions of primary palliative care to patients due to forced quarantine. Herein, we review the landscape of COVID-19 in cancer care. We also briefly share our experience and the measures in place to protect cancer patients against COVID-19 in our center.