Evolution of liver metastasis from solid pseudopapillary tumor of the pancreas

Unraveling the enigma: A comprehensive review of solid pseudopapillary tumor of the pancreas

Solid pseudopapillary tumor of the pancreas (SPTP) is a rare neoplasm predominantly observed in young females. Pathologically, CTNNB1 mutations, β-catenin nuclear accumulation, and subsequent Wnt-signaling pathway activation are the leading molecular features. Accurate preoperative diagnosis often relies on imaging techniques and endoscopic biopsies. Surgical resection remains the mainstay treatment. Risk models, such as the Fudan Prognostic Index, show promise as predictive tools for assessing the prognosis of SPTP. Establishing three types of metachronous liver metastasis can be beneficial in tailoring individualized treatment and follow-up strategies. Despite advancements, challenges persist in understanding its etiology, establishing standardized treatments for unresectable or metastatic diseases, and developing a widely recognized grading system. This comprehensive review aims to elucidate the enigma by consolidating current knowledge on the epidemiology, clinical presentation, pathology, molecular characteristics, diagnostic methods, treatment options, and prognostic factors.

Case report: Retroperitoneal solid pseudopapillary neoplasm associated with multiple hepatic metastases

Solid pseudopapillary neoplasm (SPN) is a rare tumor mostly occurring in the pancreas. They are low-grade malignant tumors of the exocrine pancreas that occasionally metastasize, usually to the liver or peritoneum. Additionally, multiple metastases of extrapancreatic SPN to the liver are extremely rare and have been reported before. This study presents a case of a 13-year-old male patient with retroperitoneal SPN and multiple hepatic metastases. The patient presented with abdominal trauma and underwent enhanced CT, which revealed upper pancreatic occupancy and three hypodense foci in the right lobe of the liver. Moreover, increased spleen size was noted. The patient's serum tumor marker CA125 was increased to 39.00 U/mL (N < 35.0 U/mL), and circulating tumor cells were elevated to 10.2 FU/3 mL (N < 8.7 FU/3 mL). The patient underwent retroperitoneal occupancy resection and splenectomy, followed by resection of liver metastases 7 months after the surgery. Furthermore, multiple liver metastases from retroperitoneal SPN were confirmed postoperatively. The patient recovered for 1 year without tumor recurrence. This case emphasizes the importance of evaluating serum tumor markers and medical imaging in young patients as well as the fact that surgery appears to be the preferred treatment option for multiple metastases in SPN.

Malignant Solid Pseudopapillary Neoplasm of the Pancreas: An Orthogonal Analysis

BACKGROUND

Pancreatic solid pseudopapillary neoplasms (SPN) are generally indolent; however, some patients present with "malignant" SPN. An orthogonal analysis of multiple datasets was performed to investigate the utility of complete surgical resection (CSR) for malignant SPN.

METHODS

A systematic review was performed for cases of malignant SPN, defined as T4, N1, and/or M1. Malignant SPN was analyzed within the National Cancer Database (NCDB) and compared with T1-3N0M0 SPN. Predictors of malignant SPN were assessed, and treatments were analyzed by using survival analysis.

RESULTS

The systematic review yielded 164 cases of malignant SPN. Of 31 children, only one died due to malignant SPN. Among adults, CSR was associated with improved disease-specific survival (DSS) (P = 0.0002). Chemotherapy did not improve malignant SPN DSS, whether resected (P = 0.8485) or not (P = 0.2219). Of 692 adults with SPN within the NCDB, 93 (13.4%) had malignant SPN. Pancreatic head location (odds ratio [OR] 2.174; 95% confidence interval [CI] 1.136-4.166; P = 0.0186) and tumor size (OR 1.154; 95% CI 1.079-1.235; P < 0.0001) associated with the malignant phenotype. Malignant SPN predicted decreased overall survival (OS) compared with T1-3N0M0 disease (P < 0.0001). Resected malignant SPN demonstrated improved OS (P < 0.0001), including resected stage IV malignant SPN (P = 0.0003). Chemotherapy did not improve OS for malignant SPN, whether resected (P = 0.8633) or not (P = 0.5734). Within a multivariable model, resection was associated with decreased hazard of death (hazard ratio 0.090; 95% CI 0.030-0.261; P < 0.0001).

CONCLUSIONS

Approximately 13% of patients with SPN present with a malignant phenotype. Pediatric cases may be less aggressive. Resection may improve survival for malignant SPN, which does not appear chemosensitive.

A refractory liver metastatic solid pseudopapillary neoplasm pancreas harbored CTNNB1 mutation showed good response to celecoxib: A case report

Solid pseudopapillary neoplasm (SPN) of the pancreas is rare relatively low-grade malignant neoplasm and metastasis rarely. Surgical resection is the primary treatment option for primary and metastatic lesions of SPN, and chemotherapy is often ineffective in non-operable SPNs. SPNs are characterized by the presence of somatic CTNNB1 exon 3 mutations, leading to the activation of Wnt/β-catenin/Cox-2 signal pathway. Here, we firstly report that a refractory liver metastatic pancreatic SPN patient after the failure of multi-line chemotherapies benefited from the Cox-2 selective inhibitor (Celecoxib) based on CTNNB1 D32V mutation detected by next-generation sequencing (NGS), achieving a more than 22-month progression-free survival without any adverse events. Our case provides a potential treatment option for liver metastatic SPN patients with CTNNB1 mutations and highlights the application of NGS for the better treatment decision making.

Grading Solid Pseudopapillary Tumors of the Pancreas: the Fudan Prognostic Index

BACKGROUND

Ki-67 has been shown to predict outcome of patients with solid pseudopapillary tumor of the pancreas (SPTP) but has not been incorporated into a formal classification system to predict recurrence-free survival (RFS).

METHODS

This is a retrospective cohort study of patients with histologically confirmed diagnosis of SPTP who had at least 1 year of follow-up at two tertiary academic centers. Survival data were assessed by Kaplan-Meier method and multivariable Cox regression model. Prognostic performance was compared among various systems.

RESULTS

A total of 193 consecutive patients were included, ranging in age from 12 to 70 years (median 33 years). Seven patients (3.6%) developed tumor recurrence. The 3-, 5-, and 10-year RFS rates were estimated at 96.9%, 96.1%, and 94.8%, respectively. For the AJCC staging system, patients with stage I had similar prognosis to those with stage II. For the ENETS staging system, patients with stage I to III had similar prognosis. Grade based on Ki-67 was superior to both the AJCC and ENETS systems for predicting survival. Multivariate analysis revealed that large tumor size [> 10 cm; hazard ratio (HR), 6.177 95% confidence interval (CI), 1.289-29.603; P = 0.023] and Ki-67 (HR, 17.199 95% CI, 4.001-73.930; P < 0.001) were independent predictors for RFS. The Fudan Prognostic Index based on the combination of Ki-67 and tumor size showed excellent discrimination for RFS and was more accurate and informative than other grading/staging systems.

CONCLUSION

The Fudan Prognostic Index better predicts RFS compared with either Ki-67 alone or the current AJCC and ENETS TNM-based staging systems.

Preoperative neutrophil-to-lymphocyte ratio predicts malignancy and recurrence-free survival of solid pseudopapillary tumor of the pancreas

BACKGROUND

Systemic inflammatory markers such as neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been shown to be prognostic for many types of pancreatic malignancy. The aim of this study was to evaluate the prognostic role of these markers in patients with solid pseudopapillary tumor of the pancreas (SPTP).

METHODS

Patients who underwent surgical resection for histologically confirmed SPTP were retrospectively reviewed in our institution. Preoperative NLR and PLR were calculated. Clinicopathologic data were correlated with the presence of malignant potential and recurrence-free survival (RFS).

RESULTS

A total of 113 patients with SPTP were included in this study. Of them, 23 were men and 90 were women, with a median age of 35 years (interquartile range, 25-44). The optimal cut-off values for malignant SPTP were 3.22 for NLR, and 75.5 for PLR, respectively. Univariate analysis showed that high NLR (>3.22) and white blood cell count more than 9.96 × 109 /L were predictive of a malignant SPTP. Meanwhile, high NLR (P = 0.001) and age more than 35 years (P = 0.026) were associated with worse RFS. On multivariable analyses, high NLR was the only independent predictor of malignant SPTP (odd ratio 6.871; 95% confidence interval [CI], 1.482-31.864; P = 0.014) and RFS (hazard ratio 12.633; 95% CI, 1.758-90.790; P = 0.012).

CONCLUSIONS

This study highlights the supportive role of preoperative NLR in predicting malignancy and RFS of SPTP patients. Further studies including a larger cohort of patients are needed to corroborate our findings.

Prediction of malignancy and adverse outcome of solid pseudopapillary tumor of the pancreas

Since solid pseudopapillary tumor of the pancreas (SPTP) was officially classified by the World Health Organization in 1996, SPTP has recently received special attention in the literature. Studies have shown that SPTP is a heterogeneous tumor, with a small percentage of patients harboring aggressive behaviors. However, criteria for malignancy grade in SPTP have not been well established. The prognosis of SPTP is generally good, with cases having a chance for long-term survival even with recurrence and/or metastasis after surgical resection. The current American Joint Committee on Cancer/Union for International Cancer Control tumor, node, metastasis staging system is not specific to SPTP. The lack of a predictive staging classification that accurately describes the heterogeneity of this disease hinders meaningful research into optimal individualized therapy. Here we summarize and discuss the associated factors proposed for appraisal of the malignant potential and adverse outcome of SPTP.