Apparent Long-Term Cure Following Conversion Therapy for Initially Unresectable Pancreatic Ductal Adenocarcinoma: A Case Report.

Locally advanced pancreatic ductal adenocarcinoma (LA-PDAC) is increasingly managed with neoadjuvant chemotherapy with the aim of tumour downstaging and potential conversion to resection. LA-PDAC is typically defined by tumour involvement of major vascular structures precluding upfront surgical resection in the absence of distant metastases. However, only a minority of patients ultimately undergo secondary surgery, and pathological complete response (pCR) remains rare. A 64-year-old male was diagnosed in 2011 with LA-PDAC involving the pancreatic neck with vascular involvement precluding upfront resection. He received systemic chemotherapy with capecitabine-cisplatin, followed by four cycles of FOLFIRINOX (oxaliplatin, irinotecan, leucovorin, and 5-fluorouracil). Restaging imaging demonstrated marked tumour regression without metastatic disease. In December 2012, he underwent total pancreatectomy and splenectomy. Histopathological examination revealed complete tumour regression (ypT0N0R0). The patient remained free of pancreatic cancer recurrence for over 13 years and ultimately died from an unrelated primary lung malignancy. Although pCR following neoadjuvant therapy for PDAC is uncommon and associated with improved survival, long-term disease-free survival beyond a decade after conversion surgery for initially unresectable disease is rarely reported. This case highlights the potential impact of tumour biology, sustained systemic response, and multidisciplinary reassessment in selected patients with LA-PDAC.