Solid Tumor Metastases to the Pancreas Diagnosed Using Fine-Needle Aspiration A Tertiary Cancer Center Experience

Objectives: Solid tumor metastases to the pancreas are rare, and only limited literature on the topic is available. In this retrospective study, we reviewed 107 cases of solid tumor metastases to the pancreas diagnosed by fine-needle aspiration (FNA) from 2005 to 2019. Methods: Information including the patients' clinical histories, radiologic and pathologic findings, treatments, and follow-up were collected. Results: The mean age of the patients was 62.4 years. The mean tumor size was 2.64 cm with even distribution throughout the pancreas ( head, neck and body, and tail). The most common primary site was the kidney; followed by the lung, skin, and breast and the gynecologic, gastrointestinal, and genitourinary tracts. The most common tumor type was carcinoma, followed by melanoma and sarcoma. In comparison to patients with nonkidney primary cancers, those with primary renal cell carcinoma had a longer median interval between primary diagnosis and metastasis (8.5 vs 4.0 years; P < .01), less often had metastasis outside the pancreas (38% vs 74%; P < .01), and had a signcantly longer 5-year survival rate (65.7% vs 24.8%; P < .01 ). Conclusions: FNA plays a crucial role in diagnosing metastases to the pancreas. Metastases originating from kidney and nonkidney primary tumors have distinct clinicopathologic features and prognoses.