Differences in Toxicity Between Ashkenazi and Sephardic Jews With Colon Cancer Treated With Adjuvant Chemotherapy: A Prospective Study

Background/Aim: Ethnicity of cancer patients is increasingly being recognized as an important factor that may influence intergroup variation in toxicity and efficacy of chemotherapy. Data from our institution suggested that differences in chemotherapy-associated toxicity are not limited to distanced ethnic subgroups, such as Caucasians, Afro-Americans, or Asians, but may exist even between two closely related Caucasian ethnic subgroups, such as Ashkenazi and Sephardic Jews. This study aimed to explore differences in severity and frequency of various side effects, including neurotoxicity between patients from the two Jewish subgroups receiving oxaliplatin-containing adjuvant chemotherapy for colon cancer (CC). Patients and Methods: We recruited 75 patients, with performance status 0-1 and no background of neuropathy between 2012 and 2016. All patients completed a neurotoxicity questionnaire (NQ) and a QoL questionnaire (QoLQ) at baseline and the NQ also at each treatment cycle; during follow up, patients filled out the NQ and the QoLQ every four months for a total of one year. Results: Of the 75 participants, 66 were evaluable for the study including 34 (52%) Sephardic and 32 (48%) Ashkenazi Jews. Grade ≥2 vomiting and diarrhea occurred more often in Sephardic than in Ashkenazi patients (p=0.008 and 0.012, respectively). Of the 66 evaluable patients, 11 (17%) developed grade 3 neurotoxicity; of these, 9 were Sephardic and 2 were Ashkenazi (p=0.028). There were no significant differences in the dynamics of QoL between both subgroups. Conclusion: Sephardic patients receiving oxaliplatin-containing regimens are at an increased risk for neurotoxicity and other side effects as compared to their Ashkenazi counterparts.