Background : While the place of radical surgery in metastatic solid cancers like colorectal and breast cancers is evolving, the same needs to be defined in patients with metastatic GBC (mGBC). The current study looked at role of radical surgery in GBC with limited metastatic disease.

Methods : Retrospective observational cohort study design was used to analyse the prospectively maintained GBC database from 1st January 2010 to 31st December 2019. This is a single institutional study conducted at Tata Memorial Centre, Mumbai (India). Patients of GBC who underwent surgical exploration and found to have low volume metastatic disease intra-operatively were included. Low metastatic disease burden was defined as either of following: microscopic disease in station 16b1 nodeN2 disease, isolated port-site metastases, low burden peritoneal disease with deposits less than 1cm, limited to adjacent omentum or adjacent diaphragm or Morrison’s pouch or a solitary discontinuous liver metastasis in the adjacent liver parenchyma.

Results : 234 patients with low volume metastatic disease detected intra-operatively were identified. Of these, 62 patients underwent radical surgery with R-0 resection of metastatic disease followed by systemic therapy while remaining 172 patients did not undergo radical surgery and were offered palliative systemic chemotherapy. Patients who underwent radical surgery had significantly superior overall survival (19 months versus 12 months, p<0.01) and superior disease-free survival (10 months versus 5 months, p<0.01) when compared to the rest. Sub-site specific analysis showed higher median overall survival with radical surgery – isolated port site metastases-23 months, en-bloc resected low volume metastases-19 months, N2 disease – 19 months as opposed to those who were offered only palliative chemotherapy – Peritoneal disease – 12 months, Station 16 node – 11 months, Liver metastases-8 months (p value = 0.001). This difference in survival was more pronounced amongst patients when operated after neoadjuvant chemotherapy. Regression analysis showed the sub-group of patients having incidental gallbladder cancers (iGBC) with limited metastases to have the most favorable outcomes with radical surgery.

Conclusions : Authors suggest a possible role for radical treatment of advanced GBC with limited metastatic burden. Neoadjuvant chemotherapy can be used for preferentially selecting patients of favorable disease biology for curative treatment. Select cases of advanced GBC can be potentially offered superior survival using varying treatment strategies.