Tumor Regression Grade and Overall Survival following Gastrectomy with Preoperative Therapy for Gastric Cancer

• Published in: Annals of surgical oncology Vol. 30; no. 6; pp. 3580 - 3589
• Main Authors: Sinnamon, Andrew J., Savoldy, Michelle, Mehta, Rutika, Dineen, Sean P., Peña, Luis R., Lauwers, Gregory Y., Pimiento, Jose M.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.06.2023; Springer Nature B.V
• Subjects: 5-Fluorouracil; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Chemotherapy; Cisplatin; Epirubicin; Fluorouracil - therapeutic use; Folinic acid; Gastrectomy; Gastric cancer; Gastrointestinal Oncology; Gastrointestinal surgery; Humans; Lymph nodes; Medical prognosis; Medicine; Medicine & Public Health; Neoadjuvant Therapy; Oncology; Oxaliplatin; Oxaliplatin - therapeutic use; Prognosis; Retrospective Studies; Stomach Neoplasms - drug therapy; Stomach Neoplasms - surgery; Surgery; Surgical Oncology; Survival; Tumors
• ISSN: 1068-9265; 1534-4681
• DOI: 10.1245/s10434-023-13151-w

Background Pre-/perioperative chemotherapy is well-established for management of locoregional gastric cancer (LRGC). The American Joint Committee on Cancer advocates histopathologic assessment of tumor regression grade (TRG) but does not endorse a specific schema. We sought to examine the prognostic value of the recently revised National Comprehensive Cancer Network (NCCN) definition of TRG specifying TRG0 as no disease in primary tumor or lymph nodes. Patients and Methods Patients with clinical-stage T2+/N+/M0 LRGC receiving preoperative chemotherapy and curative-intent gastrectomy were identified (2000–2020). TRG using the current NCCN definition was retrospectively assigned. Factors associated with TRG were examined using ordinal logistic regression and overall survival (OS) was assessed using the Kaplan–Meier method and Cox regression. Results Among 117 patients, the most common chemotherapy regimen was epirubicin, cisplatin, plus fluorouracil or capecitabine (ECF/ECX) ( n = 48, 41%), followed by folinic acid, fluorouracil, and oxaliplatin (FOLFOX) ( n = 30, 26%), and fluorouracil, leucovorin, oxaliplatin, plus docetaxel (FLOT) ( n = 13, 11%). TRG3 was the most common histopathologic response ( n = 68, 58%), followed by TRG2 ( n = 25, 21%), TRG1 ( n = 18, 15%), and, lastly, TRG0 ( n = 6, 5.1%). The only preoperative factor independently associated with lower TRG was gastroesophageal junction tumor location (OR 0.24, p = 0.012). Higher TRG was independently associated with worse OS in a stepwise fashion (HR 1.49, p = 0.026). Posttreatment pathologic lymph node status was the strongest prognostic factor (HR 1.93, p = 0.026). Independent prognostic value of TRG and ypT stage could not be shown due to substantial overlap. Conclusions TRG using the contemporary NCCN definition is associated with OS in LRGC. TRG0 is uncommon but with excellent prognosis. ypN status is the strongest prognostic factor and the revised NCCN definition acknowledging this is appropriate.