Marco Dioguardi Burgio1,2, Jérome Cros3, Nicola Panvini4, Thomas Depoilly3, Anne Couvelard3, Philippe Ruszniewski5, Louis de Mestier5, Olivia Hentic5, Alain Sauvanet6, Safi Dokmak6, Alex Faccinetto4, Maxime Ronot7,4, Valérie Vilgrain7,4. 1. Université de Paris, INSERM U1149 "centre de recherche sur l'inflammation," CRI, F-75018, Paris, France. marco.dioguardiburgio@aphp.fr. 2. Department of Radiology, AP-HP Nord, Hôpital Beaujon, 100 Boulevard du Général Leclerc, 92110, Clichy, France. marco.dioguardiburgio@aphp.fr. 3. Department of Pathology, AP-HP Nord, Hôpital Beaujon, 100 Boulevard du Général Leclerc, 92110, Clichy, France. 4. Department of Radiology, AP-HP Nord, Hôpital Beaujon, 100 Boulevard du Général Leclerc, 92110, Clichy, France. 5. Department of Gastroenterology-Pancreatology, ENETS Centre of Excellence AP-HP Nord, Hôpital Beaujon, 100 Boulevard du Général Leclerc, 92110, Clichy, France. 6. Department of HBP Surgery, AP-HP Nord, Hôpital Beaujon, 100 Boulevard du Général Leclerc, 92110, Clichy, France. 7. Université de Paris, INSERM U1149 "centre de recherche sur l'inflammation," CRI, F-75018, Paris, France.
Abstract
OBJECTIVES: Dilatation of the main pancreatic duct (MPD) is rare in pancreatic neuroendocrine neoplasm (panNEN) and may be due to different mechanisms. We compared the imaging and pathological characteristics as well as the outcome after resection of positive (S+) and negative (S-) serotonin immunoreactive panNENs causing MPD dilatation. METHODS: This retrospective study included patients with panNEN, with MPD dilatation (≥ 4 mm) on preoperative CT/MRI and resected between 2005 and 2019. Clinical, radiological, and pathological features were compared between S+ and S- panNENs. Imaging features associated with S+ panNEN were identified using logistic regression analysis. The diagnostic performance of imaging for the differentiation of S+ and S- panNENs was assessed by ROC curve analysis. Recurrence-free survival (RFS) was compared between the two groups. RESULTS: The final population of 60 panNENs included 20/60 (33%) S+ panNENs. S+ panNENs were smaller (median 12.5 mm vs. 33 mm; p < 0.01), more frequently hyperattenuating/intense on portal venous phase at CT/MRI (95% vs. 25%, p < 0.01), and presented with more fibrotic stroma on pathology (60.7 ± 16% vs. 40.7 ± 12.8%; p < 0.01) than S- panNENs. Tumor size was the only imaging factor associated with S+ panNEN on multivariate analysis. A tumor size ≤ 20 mm had 95% sensitivity and 90% specificity for the diagnosis of S+ panNEN. Among 52 patients without synchronous liver metastases, recurrence occurred in 1/20 (5%) with S+ panNEN and 18/32 (56%) with S- panNEN (p < 0.01). Median RFS was not reached in S+ panNENs and was 31.3 months in S- panNENs (p < 0.01). CONCLUSIONS: In panNENs with MPD dilatation, serotonin positivity is associated with smaller size, extensive fibrotic stroma, and better long-term outcomes. KEY POINTS: • S+ panNENs showed a higher percentage of fibrotic stroma, higher microvessel density, and lower proliferation index (Ki-67) compared to S- panNENs. • Radiologically, S+ panNENs causing dilatation of the MPD were characterized by a small size (< = 20 mm) and a persistent enhancement on portal phase on both CT and MRI. • Patients with S+ panNENs presented with longer RFS when compared to those with S- panNENs.
OBJECTIVES: Dilatation of the main pancreatic duct (MPD) is rare in pancreatic neuroendocrine neoplasm (panNEN) and may be due to different mechanisms. We compared the imaging and pathological characteristics as well as the outcome after resection of positive (S+) and negative (S-) serotonin immunoreactive panNENs causing MPD dilatation. METHODS: This retrospective study included patients with panNEN, with MPD dilatation (≥ 4 mm) on preoperative CT/MRI and resected between 2005 and 2019. Clinical, radiological, and pathological features were compared between S+ and S- panNENs. Imaging features associated with S+ panNEN were identified using logistic regression analysis. The diagnostic performance of imaging for the differentiation of S+ and S- panNENs was assessed by ROC curve analysis. Recurrence-free survival (RFS) was compared between the two groups. RESULTS: The final population of 60 panNENs included 20/60 (33%) S+ panNENs. S+ panNENs were smaller (median 12.5 mm vs. 33 mm; p < 0.01), more frequently hyperattenuating/intense on portal venous phase at CT/MRI (95% vs. 25%, p < 0.01), and presented with more fibrotic stroma on pathology (60.7 ± 16% vs. 40.7 ± 12.8%; p < 0.01) than S- panNENs. Tumor size was the only imaging factor associated with S+ panNEN on multivariate analysis. A tumor size ≤ 20 mm had 95% sensitivity and 90% specificity for the diagnosis of S+ panNEN. Among 52 patients without synchronous liver metastases, recurrence occurred in 1/20 (5%) with S+ panNEN and 18/32 (56%) with S- panNEN (p < 0.01). Median RFS was not reached in S+ panNENs and was 31.3 months in S- panNENs (p < 0.01). CONCLUSIONS: In panNENs with MPD dilatation, serotonin positivity is associated with smaller size, extensive fibrotic stroma, and better long-term outcomes. KEY POINTS: • S+ panNENs showed a higher percentage of fibrotic stroma, higher microvessel density, and lower proliferation index (Ki-67) compared to S- panNENs. • Radiologically, S+ panNENs causing dilatation of the MPD were characterized by a small size (< = 20 mm) and a persistent enhancement on portal phase on both CT and MRI. • Patients with S+ panNENs presented with longer RFS when compared to those with S- panNENs.
Authors: Anna Gallotti; Rocio Perez Johnston; Pietro A Bonaffini; Thun Ingkakul; Vikram Deshpande; Carlos Fernández-del Castillo; Dushyant V Sahani Journal: AJR Am J Roentgenol Date: 2013-02 Impact factor: 3.959