CTD-2

Introduction The overall survival (OS) of metastatic colorectal cancers (mCRCs) in clinical practice and resource-constrained low- and middle-income countries (LMICS) like India is not known. Materials and Methods Data of patients with mCRC treated between January 2013 and August 2017 were accessed from a prospectively maintained database. Demographics, disease characteristics, chemotherapeutic regimens, use of monoclonal antibodies, and survival outcomes in treated patients were collected and analyzed. Costs of treatment options as off 2017 were also interpreted. Results The data of 403 patients satisfied prespecified inclusion criteria and were included for analysis. The median age of the cohort was 48 years (range: 17–86) with a predominance of rectal cancers (63.3%), liver alone metastases (47.1%), and resected primary (69.7%). Signet ring histology was present in 82 patients (20.3%). The most commonly used first-line regimen (CT1) was modified capecitabine-oxaliplatin (53.3%). Two hundred and nineteen patients (54.3%) received second-line systemic therapy (CT2). Patients received a median of two lines of therapy (range: 1–6). MoAbs were used by 48 patients (13.4%) with CT1 and 34 patients (15.5%) with CT2. Median OS of the entire cohort was 17.61 months (95% confidence interval: 15.48–19.74), which was within the predicted range, as per investigator hypothesis. The presence of signet ring histology (p<0.001), raised carcinoembryonic antigen at baseline (p=0.017), and the absence of a resected primary (p<0.001) predicted inferior median OS. Conclusions Survival of patients with mCRC in a resource-constrained LMIC scenario like India is approximately 12 to 15 months lower than published trial data. Limited access to targeted therapy and newer expensive treatment options due to financial constraints may contribute to this disparity.

Purpose The survival benefit of first-line chemotherapy (CT1) for biliary tract cancer (BTC) is now established but the role of second-line chemotherapy (CT2) has not been fully elucidated yet. Methods Consecutive advanced BTC patients receiving CT1 between 2000 and 2016 were retrospectively studied. We investigated the safety and efficacy of CT2, prognostic factors for residual survival after CT1, and explored subgroups who would benefit from CT2. Results Among 294 patients receiving CT1 for advanced BTC, CT2 was given in 139 patients (47%). CT2 provided a response rate of 4%, a disease control rate of 52%, a median progression-free survival of 2.8 and overall survival of 7.7 months, respectively. CT2 was associated with longer residual survival after CT1 (hazard ratio [HR] 0.61, p < 0.01), as well as PS of 0-1 (HR 0.53, p < 0.01), best response to CT1 of PD (HR 1.46, p = 0.01), and CEA ≥5.0 ng/mL (HR 1.69, p < 0.01). The effects of CT2 were homogeneous across almost all subgroups but were more prominent in patients with age ≥ 70 years (HR 0.32, p for interaction =0.02), CA19-9 ≥ 200 IU/mL (HR 0.41, p for interaction = 0.08) and CEA ≥5.0 ng/mL (HR 0.41, p for interaction = 0.06). Conclusions The introduction rate of CT2 was 47%. Although the efficacy of CT2 was modest in terms of tumor response, it was associated with better survival. Further investigations are necessary both to develop more effective regimens and to select patients who will benefit from CT2.