BACKGROUND Pancreatic adenosquamous carcinoma has a poor prognosis, with limited prospective trial data to guide optimal treatment. The potential impact of drug metabolism on the treatment response of patients with pancreatic adenosquamous carcinoma is largely unknown. CASE PRESENTATION We describe the case of a 51 year old woman with pancreatic adenosquamous carcinoma who, following surgical resection, experienced early disease relapse during adjuvant gemcitabine therapy. Paradoxically, this was followed by an exceptional response to capecitabine therapy lasting 34.6 months. Strong expression of cytidine deaminase was detected within the tumour. CONCLUSIONS This case study demonstrates that early relapse during adjuvant chemotherapy for pancreatic adenosquamous carcinoma may be compatible with a subsequent exceptional response to second line chemotherapy, an important observation given the poor overall prognosis of patients with adenosquamous carcinoma. Cytidine deaminase is predicted to inactivate gemcitabine and, conversely, catalyze capecitabine activation. We discuss strong intra-tumoural expression of cytidine deaminase as a potential mechanism to explain this patient's disparate responses to gemcitabine and capecitabine therapy, and highlight the benefit that may be gained from considering similar determinants of response to chemotherapy in clinical practice.

中文翻译：

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肿瘤内胞苷脱氨酶表达强烈的胰腺腺鳞癌患者，辅助吉西他滨早期复发与二线卡培他滨化疗的特殊反应相关：病例报告。


背景胰腺腺鳞癌预后较差，指导最佳治疗的前瞻性试验数据有限。药物代谢对胰腺腺鳞癌患者治疗反应的潜在影响在很大程度上尚不清楚。病例介绍 我们描述了一名患有胰腺腺鳞癌的 51 岁女性患者的病例，她在手术切除后，在辅助吉西他滨治疗期间出现了早期疾病复发。矛盾的是，随后卡培他滨治疗出现了持续 34.6 个月的异常反应。在肿瘤内检测到胞苷脱氨酶的强烈表达。结论 本病例研究表明，胰腺腺鳞癌辅助化疗期间的早期复发可能与随后对二线化疗的异常反应相一致，考虑到腺鳞癌患者总体预后不良，这是一个重要的观察结果。胞苷脱氨酶预计会使吉西他滨失活，相反，会催化卡培他滨激活。我们讨论了胞苷脱氨酶的强肿瘤内表达作为解释该患者对吉西他滨和卡培他滨治疗的不同反应的潜在机制，并强调了在临床实践中考虑化疗反应的类似决定因素可能获得的益处。