Complete histopathologic examination of risk reduction gastrectomy specimens for CDH1 germline mutation: Is it warranted in routine clinical practice?

Aims: CDH1 germline mutation is associated with high penetrance of hereditary diffuse gastric cancer (HDGC). Due to the lack of endoscopically identifiable lesions, routine surveillance is ineffective in the early detection of gastric cancer, and risk-reduction gastrectomy is often recommended. Many academic pathology departments elect to submit the entire gastrectomy specimen for histological examination, which is associated with significantly increased cost, technical and professional time, and turnaround time. Methods: We present our experience with 5 completely submitted and 2 representatively submitted prophylactic total gastrectomy cases in HDGC patients. Results: Multifocal intramucosal signet ring cell carcinoma was identified in all cases except one, in which only in situ carcinoma was identified. The tumoral foci (2 to 35 per case; average 14.4) were concentrated in proximal stomach. No submucosal invasion or nodal metastases was seen in any case. The final stage was either stage 0 (pTisN0cM0) or stage 1a (pT1aN0cM0). Conclusions: Our findings are in line with that reported in the literature. Considering that deeply invasive carcinoma is very rare in this situation, and no further treatment is indicated for the vast majority of those patients, complete submission and pathologic examination of the entire stomach provides little additional value for routine clinical management. We propose a two-step approach with targeted submission of the proximal stomach, and subsequent entire submission of the remaining stomach if no intramucosal carcinoma is identified during the initial targeted examination.