Dealing with pancreatic metastases from renal cell cancer: the experience of three Italian high-volume pancreatic surgical centres

Purpose: Pancreatic metastases (PM) from renal-cell carcinoma (RCC) are rare, and have a better prognosis when compared to other pancreatic malignancies. A surgical treatment may have a role for improving overall (OS) and disease-free survival (DFS). Materials and methods: Clinical records of patients with PM from RCC observed from November 2000 to February 2019 in three Italian high-volume pancreatic surgical centres were retrieved retrospectively. Clinical-pathological features, surgical management and follow-up (FU) were evaluated. FU closed in December 2019. Results: Thirty-nine patients (21 M/18 F, averaging 65 years) were enrolled. Nephrectomy for primary (23 left/16 right), was performed 73 months (up to 24 years) before detection of PM. PM were multiple in 20 (54%) of cases, mostly (72%) located in the body-tail region. Cross-sectional and functional total body imaging studies (18F-FDG-PET/CT, 68Ga-PET/CT or Octreoscan scintigraphy) were performed. Functional studies resulted positive for a pancreatic lesion in 62% of patients, and notably, 68Ga-PET/CT was positive in all cases. Preoperative diagnosis was correct in 77% of cases. Median tumour size was 3.0 (range 0.7-7.5) cm. Surgery consisted in 33 standard resections (13 distal, 12 total pancreatectomy, 8 pancreatico-duodenectomy), and 6 limited resections (other parenchyma-sparing procedures) . Median operative time was 350 (range 150-720) minutes. Median blood loss was 400 (100-1300) ml. Overall morbidity was 38.5%, including 4 grade B pancreatic fistula and 2 haemorrhage (without reoperation). Operative mortality was 2.6% (1 died from pulmonary embolism). Median hospital stay was 12 (range 6-133) days. Late exocrine insufficiency occurred in 43% and diabetes in 47% of patients. After a median DFS of 30 (range 3-201) months, 19/36 (53%) patients experienced a disease recurrence; only 5 patients had pancreatic relapse. After a median FU of 68 months (up to 17 years), 20 (56%) patients are still alive, 13 of them without evidence of disease. Conclusions: RCC metastases to the pancreas may arise late, up to 24 years after nephrectomy. 68Ga-PET/CT may play a role in the long FU of these patients, detecting PM and extra-pancreatic metastases. Surgical treatment may allow a long DFS (up to 17 years) in more than one third of cases.