Prognostic Enigma of Pancreatic Solid Pseudopapillary Neoplasm: A Single-Center Experience of 63 Patients

Background: Studies investigating prognostic factors of solid pseudopapillary neoplasm (SPN) have been published with conflicting findings.

Methods: Retrospective analysis of 63 consecutive cases of SPN in our institution from January 2010 to December 2019 was carried out. The clinicopathological features, treatment practices along with survival associations were collected and analyzed.

Results: Fifteen patients (23.8%) were male, and 48 (76.2%) were female, with a median age of 34.0 ± 14.5 years. The larger tumor size was correlated with the more mixed components (p = 0.000) and the higher Ki-67 index (p = 0.042). No recurrence was found in the nine patients whose tumors fulfilled the WHO criteria for malignancy due to the presence of at least perineural invasion (6.4%), angiovascular invasion (2.3%), and/or adjacent organ invasion (6.4%). Microscopic infiltrative growth was detected in 9 (14.3%) tumors, which was correlated significantly with the WHO criteria (p = 0.002), capsule invasion (p = 0.005), and pancreatic parenchyma invasion (p = 0.001), but not with disease-free survival (p = 0.13). CD99 was found to be positively expressed in 88.9% (40/45) of tumors and more likely to have depressed Ki-67 index (p = 0.016). After a median follow-up of 58 months, only two patients (3.2%) had a recurrence after their first operation outside of our hospital. No patient died due to tumor progression.

Conclusions: Although survival is favorable with aggressive surgery, it is actually difficult to assess the prognostic factors of resected SPNs. Future investigations into the role of clinicopathological evaluation will unveil the prognostic enigma of pancreatic SPN after resection.

Case Report: Targeted Therapy for Metastatic Solid Pseudopapillary Neoplasm of the Pancreas With CTNNB1 and PTEN Mutations

Background

Solid pseudopapillary neoplasm (SPN) of the pancreas shows an indolent clinical behavior in cases undergoing surgical resection. The efficacy of combination therapy in the metastatic extrapancreatic SPN treatment remains largely unknown and a clinical challenge.

Case Presentation

We report a case of a metastatic pancreatic SPN in a 45-year-old woman who presented with an aggressive peritoneal dissemination and hepatic metastases and still showed an indolent clinical course with combination therapy with repeated surgery and targeted therapy. Although the follow-up effect remains to be seen, this is the first report of practical experience of the targeted agents sunitinib and everolimus in metastatic SPN tumors based on the mutation status of PTEN (c.379G>A; p.G127R) and CTNNB1 (c.98C>G; p.S33C). To our knowledge, the PTEN variant identified in this case has not been previously reported in SPN.

Conclusion

Evidence on variant genetics indicates that future molecular studies may not only help to explain the mechanism of SPN occurrence and development but are also more likely to direct to future precision treatments.

[Application of three-dimensional visualization in pancreatic tumor: a pilot study]

Objective: To study the value of three-dimensional(3D) visualization in the diagnosis and surgical treatment for pancreatic tumor. Methods: From June to September 2016, 26 patients with pancreatic tumors in Jinling Hospital, Medical School of Nanjing University were involved. The study included 26 patients(8 females and 18 males) with mean age of (57±12)years (ranging from 23 to 77 years). And there were 20 malignant tumors and 6 benign tumors. All of them were examined with abdominal thin slice CT scanning and the CT images were imported into 3D visualization system for 3D visualization. The main elements examined by 3D visualization included tumor shape, size, and location; distribution and morphology of the peripancreatic lymph node; the relationships among neoplasms, organs and blood vessels. Results: Among the 26 patients, there were 21 cases with pancreatic cancer, of which 15 cases successfully underwent standard pancreatectomy. All patients were operated underwent accurate assessment. The 3D model demonstrated the origination and bifurcations of blood vessels, and the relationships among neoplasms, organs and blood vessels efficiently. The 3D technique could facilitate to evaluate response of neiadjuvant chemotherapy in the pancreatic cancer patients (n=5).3D reconstruction could detect the lymph-node metastases accurately (n=12) in patients with pancreatic cancer. 3D reconstruction were applied to evaluate the the size and range of tumor on 5 cases. Conclusions: 3D reconstruction allows stereoscopic identification of the spatial relationships between physiologic and pathologic structures.The 3D technique could facilitate to evaluate distribution and morphology of the peripancreatic lymph node, and to evaluate the relationships among neoplasms, organs and blood vessels.