Prognostic Analysis of Primary Breast Signet Ring Cell Carcinoma and Mucinous Breast Adenocarcinoma: A SEER Population-Based Study

Breast cancer is the most common malignancy in women around the world. Information on the incidence and mortality of breast cancer is essential for planning health measures. This study aimed to investigate the incidence and mortality of breast cancer in the world using age-specific incidence and mortality rates for the year 2012 acquired from the global cancer project (GLOBOCAN 2012) as well as data about incidence and mortality of the cancer based on national reports. It was estimated that 1,671,149 new cases of breast cancer were identified and 521,907 cases of deaths due to breast cancer occurred in the world in 2012. According to GLOBOCAN, it is the most common cancer in women, accounting for 25.1% of all cancers. Breast cancer incidence in developed countries is higher, while relative mortality is greatest in less developed countries. Education of women is suggested in all countries for early detection and treatment. Plans for the control and prevention of this cancer must be a high priority for health policy makers; also, it is necessary to increase awareness of risk factors and early detection in less developed countries.

While the incidence of gastric cancer has decreased worldwide in recent decades, the incidence of signet-ring cell carcinoma (SRCC) is rising. SRCC has a specific epidemiology and oncogenesis and has two forms: early gastric cancer, which can be resected endoscopically in some cases and which has a better outcome than non-SRCC, and advanced gastric cancer, which is generally thought to have a worse prognosis and lower chemosensitivity than non-SRCC. However, the prognosis of SRCC and its chemosensitivity with specific regimens are still controversial as SRCC is not specifically identified in most studies and its poor prognosis may be due to its more advanced stage. It therefore remains unclear if a specific therapeutic strategy is justified, as the benefit of perioperative chemotherapy and the value of taxane-based chemotherapy are unclear. In this review we analyze recent data on the epidemiology, oncogenesis, prognosis and specific therapeutic strategies in both early and advanced SRCC of the stomach and in hereditary diffuse gastric cancer.

The aim of this retrospective study was to evaluate the survival impact of perioperative chemotherapy (PCT) in patients with gastric signet ring cell (SRC) adenocarcinoma. PCT is a standard treatment for advanced resectable gastric adenocarcinoma (GA). SRC has a worse prognosis compared to non-SRC and the chemosensitivity of SRC is uncertain. Among 3010 patients registered in 19 French centers between January 1997 and January 2010, 1050 (34.9%) were diagnosed with SRC. Of those treated with curative intent (n = 924), 171 (18.5%) received PCT with surgery (PCT group), whereas 753 (81.5%) were treated with primary surgery (S group). PCT was based mainly on a fluorouracil-platinum doublet or triplet regimen. The groups were comparable regarding age, gender, American Society of Anesthesiologists (ASA) score, malnutrition, tumor location and cTNM stage. 60 patients did not undergo resection because of tumor progression (10) or metastases (50) found at operation. The R0 resection rates were 65.9% and 62.3% in the S and PCT groups, respectively (P = 0.308). Fewer patients received adjuvant chemotherapy in the S group than in the PCT group (35.2% vs. 66.5%, P < 0.001). At a median follow-up of 31.5 months, the median survival was shorter in the PCT group (12.8 vs. 14.0 months, P = 0.043). On multivariate analysis, PCT was found to be an independent predictor of poor survival (HR = 1.4, 95% CI 1.1-1.9, P = 0.042). PCT provides no survival benefit in patients with gastric SRC. Clinical Trial.gov record: ADCI001, Clinical Trial.gov identifier NCT01249859.