Abstract
RATIONALE: Pancreatic cancer (PC) frequently recurs after curative surgery. Pulmonary metastases are uncommon but may indicate more indolent disease. The benefit of aggressive treatment in cases with minimal dissemination remains unclear. PATIENT CONCERNS: A 77-year-old man developed a solitary pulmonary nodule 25 months after distal pancreatectomy for stage IB PC. Tumor markers remained within normal range. DIAGNOSES: Thoracoscopic resection confirmed metastatic PC. Pleural lavage cytology was positive, indicating microscopic dissemination. INTERVENTIONS: Systemic chemotherapy was administered for over 2 years using various regimens: gemcitabine + nab-paclitaxel, nano-liposomal irinotecan + fluorouracil + leucovorin, gemcitabine + S-1, and modified fluorouracil + leucovorin + irinotecan + oxaliplatin. Treatment was paused due to fatigue when the disease and markers stabilized. OUTCOMES: After treatment interruption, a recurrent pleural mass emerged with elevated CA19-9. Chemotherapy was resumed, achieving renewed control. All standard regimens were eventually exhausted, and genomic profiling revealed no actionable mutations. The patient remains alive and stable 4.7 years after metastasis, but the optimal treatment duration remains unclear. LESSONS: This case illustrates the challenge of managing chemosensitive but incurable PC with oligometastasis and minimal dissemination. It highlights the limitations of tumor markers for early recurrence detection and the difficulty in determining treatment length when therapeutic options are depleted. Individualized, sustained therapy can offer prolonged disease control. In this case, systemic treatment was continued beyond standard timelines, prioritizing disease suppression despite treatment fatigue.