Calcium channel blockers in pancreatic cancer: increased overall survival in a retrospective cohort study.

Repurposing commonly prescribed noncancer medications for use in oncology has substantial advantages over de-novo development of anticancer drugs. Calcium signalling has been implicated in many of the hallmarks of cancer. Previous in-vitro and in-vivo studies have shown that calcium channel blockers (CCBs) are able to promote apoptosis, inhibit proliferation and prevent invasion and metastasis in a variety of cancer types. This retrospective cohort study aimed to translate this into the clinic by investigating the effect of CCBs on survival in pancreatic cancer. One hundred sixty-four patients with unresectable pancreatic ductal adenocarcinoma were included. Data were collected on CCB prescription, and for a range of other potentially important prognostic factors: ECOG performance status, AJCC cancer stage, chemotherapy regimen, radiotherapy, age, hypertension and sex. Participants prescribed CCB (n = 30) were more likely to be older (P = 0.004) and have hypertension (P < 0.0005); baseline demographics were otherwise similar between groups. On adjusted cox regression patients prescribed CCBs demonstrated significantly improved overall survival; hazard ratio -0.496 (0.297-0.827; P = 0.007). Performance status (P < 0.0005), tumour stage (P < 0.0005), chemotherapy regimen (P < 0.0005), radiotherapy (0.002) and age (P = 0.012) were also independent predictors of survival. The Kaplan-Meier estimated median survival was 15.3 months for patients prescribed CCBs versus 10.1 months for patients not prescribed CCBs (P = 0.131). This study supports previous work suggesting CCBs may be beneficial in pancreatic cancer. Further work on larger datasets will allow for subgroup analysis delineating the effects of specific CCBs in combination with different forms of chemotherapy, paving the way for future prospective studies.