e16716 Background: Gallbladder cancer (GBC) is an uncommon but highly fatal malignancy. Surgery remains the only potentially curative treatment for GBC. The role of neoadjuvant chemotherapy in patients with locally advanced GBC undergoing surgery is unknown. We studied the association of neoadjuvant chemotherapy on survival in locally advanced GBC patients who underwent resection. Methods: We identified adult patients with locally advanced (stage III-IV) GBC who underwent definitive surgery between 2004 and 2016 using the National Cancer Database. Treatment was categorized as neoadjuvant chemotherapy plus surgery (NAT), surgery plus adjuvant therapy (AT), and surgery alone (SA). Categorical variables were compared using the chi-square test with Bonferroni correction. Kaplan-Meier and Cox regression were used for survival analyses. We used 1:3 nearest neighbor propensity score matching based on NAT for each group. Results: Out of a total of 5,962 patients, 122 (2.2%) received NAT, 2934 (53.6%) AT, and 2421 (44.2%) SA. NAT was associated with private insurance and treatment at an academic/research facility (all p < .001) while SA patients were older, Hispanic, had government insurance, and higher comorbidities (all p < .001). Although all groups had similar lymph node assessment (NAT: 45%, AT: 46%, SA: 37%, p < .001), NAT was associated with lymph node negative disease (NAT 23%, AT 13.2%, SA 13.2%, p < .001). Median overall survival was higher in NAT compared to AT or SA (21 vs. 14 vs. 6 months, p < .001) which persisted after propensity score matching (21 vs. 15 vs. 9 months, p < .001) and multivariable regression analysis (Table). In node positive GBC, NAT was associated with improved median overall survival (NAT 24, AT 18, SA 8 months, p < .001). Conclusions: NAT is infrequently used in patients with locally advanced GBC. NAT is associated with improved median overall survival compared to AT and SA, and appears to be most beneficial in node positive disease. Prospective studies are needed to evaluate the role of neoadjuvant chemotherapy in locally advanced GB. [Table: see text]
Role of Tc99m-Sestamibi scintimammography in assessing response to neoadjuvant chemotherapy in patients with locally advanced breast cancer
