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

Solid pseudopapillary epithelial neoplasm of the pancreas with liver metastasis

A girl in early adolescence presented with complaints of abdominal pain lasting for 4 months, along with a palpable lump in the epigastric region. A CT scan revealed a large solid-cystic mass lesion measuring 9.5×10.7×12.1 cm, involving the body and tail of the pancreas. Additionally, well-defined hypodense lesions in the liver, localised to segments VIII and IVa, were observed, with the aetiology being indeterminate. An endoscopic ultrasound-guided biopsy of the pancreatic mass confirmed a diagnosis of solid pseudopapillary epithelial neoplasm (SPEN). Ultrasonography (USG) of the liver suggested liver metastasis. Surgical excision of the pancreatic mass and complete excision of the liver metastases were performed with the aid of intraoperative USG. No other sites of metastasis were identified. Liver surface masses, measuring 4×3 cm and 5×3 cm in segments VIII and IVa, respectively, were excised, along with a 13×10×6 cm mass in the pancreatic body and tail. Microscopic examination revealed tumour cells arranged in pseudopapillary and solid patterns. The cells were round to oval with eosinophilic cytoplasm, and areas of necrosis, hyalinisation, cholesterol clefts and calcification were identified, consistent with SPEN. The liver lesions were confirmed as metastases of SPEN. All surgical margins were clear, and the three lymph nodes examined were free of tumour involvement. Immunohistochemistry was negative for synaptophysin and chromogranin, supporting the diagnosis of SPEN. Less than 2% of the tumour cells were positive for Ki-67. A final diagnosis of SPEN of the pancreas with liver metastases was established. The patient is currently on routine follow-up and remains disease-free 4 months postsurgery.

A narrative review on rare types of pancreatic cancer: should they be treated as pancreatic ductal adenocarcinomas?

Pancreatic cancer is one of the deadliest malignancies in humans and it is expected to play a bigger part in cancer burden in the years to come. Pancreatic ductal adenocarcinoma (PDAC) represents 85% of all primary pancreatic malignancies. Recently, much attention has been given to PDAC, with significant advances in the understanding of the mechanisms underpinning disease initiation and progression, along with noticeable improvements in overall survival in both localized and metastatic settings. However, given their rarity, rare histological subtypes of pancreatic cancer have been underappreciated and are frequently treated as PDAC, even though they might present non-overlapping molecular alterations and clinical behavior. While some of these rare histological subtypes are true variants of PDAC that should be treated likewise, others represent separate clinicopathological entities, warranting a different therapeutic approach. In this review, we highlight clinical, pathological, and molecular aspects of rare histological types of pancreatic cancer, along with the currently available data to guide treatment decisions.

Solid pseudopapillary neoplasm of the pancreas with hepatic metastases: problems and strategies

Background

Solid pseudopapillary neoplasms of the pancreas with hepatic metastases are infrequent and difficult to diagnose, and treatment is uncertain.

Methods

A retrospective analysis of clinical data from patients with pancreatic solid pseudopapillary neoplasm (SPN) hepatic metastases who underwent surgery at the First Hospital of Jilin University from January 2005 to December 2021 was conducted. A total of 287 patients with SPN were included in the study, of which 8 (3%) developed liver metastases, all of whom were treated surgically and recovered well after surgery. The clinical presentation, imaging features, surgical treatment, histopathological examination, and postoperative follow-up data (mean 70 months; range 28-138 months) of the patients were recorded and analyzed. Clinical response strategies can be derived by reviewing previous studies on hepatic metastases of SPNs.

Results

For resectable hepatic metastases from pancreatic solid pseudopapillary neoplasms, early surgery with total resection of the primary tumor and metastasis has shown great efficiency and is associated with patient good prognosis. In patients presenting unresectable hepatic metastases, aggressive tumor reduction surgery resulted in the alleviation of clinical symptoms and reduction of tumor burden while potentially achieving long-term survival.

Conclusion

For hepatic metastases of SPNs, a preoperative liver tissue biopsy is beneficial for a definitive diagnosis. Surgery demonstrates excellent therapeutic efficacy and is considered the preferred curative treatment approach. This paper presents clinical experiences with SPN-related hepatic metastases at the Affiliated Hospital of Jilin University, which can be used to guide patient counseling in clinical practice.

Solid pseudopapillary neoplasm (SPN) of the pancreas: current understanding on its malignant potential and management

Solid pseudopapillary neoplasms (SPN) of the pancreas are presently recognized as low-grade malignant tumors that are frequently observed in young females. This tumor has a low incidence and is associated with an excellent prognosis following surgical resection. Typical SPNs primarily affect the pancreas and tend to have moderate or asymptomatic manifestations. Based on retrospective research, it is anticipated that patients with SPN can achieve disease-free survival, even in cases when metastasis is detected during inspection. However, the incidence of malignant SPN has been consistently underestimated, as evidenced by recent research findings. Malignancy of SPN primarily encompasses invasion and infiltration, metastasis, and recurrence after R0 resection. Imaging technologies such as Ultrasound, Computed Tomography, Magnetic Resonance Imaging, and Position Emission Tomography are capable of preliminarily identifying malignant SPN, which is primarily based on its invasive clinical features. Research on risk factors of malignant SPN revealed that larger tumor size, Ki-67 index, and several other parameters had significant correlations with invasive tumor behavior. Pathologic features of malignant SPNs overlay other pancreatic tumors, nevertheless they can provide valuable assistance in the process of diagnosis. Several confirmed specific pathologic biomarkers are related to its cellular origin, characteristic gene mutation, and cell proliferation. Considering the invasiveness of malignant SPN, it is imperative to enhance the comprehensiveness of its therapy. Tumor resection remains a suggested course of action in line with typical SPN, and additional lymph node dissection is seen as reasonable. Compared to benign SPNs, malignant SPNs have worse prognosis, underscoring the necessity of early identification and treatment in comprehensive medical centers to get improved clinical outcomes.

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.

Solid pseudopapillary neoplasm of the pancreas: a retrospective study of 195 cases

Objective

Solid pseudopapillary neoplasm of the pancreas (SPN) is a rare exocrine tumor of the pancreas. The aim of our study is to summarize the clinical features of SPN and to analyze the risk factors for malignant SPN.

Methods

From May 2013 to September 2022, patients who were pathologically confirmed to have SPN were retrospectively reviewed. Demographic data, clinical and pathological features, follow-up data were collected and analyzed. To investigate the factors influencing the benign or malignant nature of SPN, we employed logistic regression. Additionally, we utilized Kaplan-Meier curves to depict and analyze the overall prognosis.

Results

A total of 195 patients were included, 163 of whom were female and the average age of all patients was 31.7 years old. Among 195 patients, 101 patients (51.8%) had no obvious clinical symptoms and their pancreatic lesions were detected during routine examination. The primary symptom was abdominal pain and distension in 64 cases (32.8%). The maximum diameter of SPN tumors ranged from 1-17 cm (mean 6.19 cm). Forty-eight postoperative complications developed in 43 (22.1%) patients. After a median follow-up duration of 44.5 months, the overall 5-year survival rate was 98.8% and the recurrence rate was 1.5%. Furthermore, we observed a statistically significant difference in the completeness of the tumor capsule between benign and malignant SPN.

Conclusion

SPN is associated with a favorable long-term survival after surgery in our large sample size cohort. For malignant SPN, tumor capsule incompleteness is an independent risk factor.

Preoperative CT histogram analysis to predict the expression of Ki-67 in solid pseudopapillary tumours of the pancreas

AIM

To explore the value of preoperative computed tomography (CT) histogram features in predicting the expression status of Ki-67 in patients with solid pseudopapillary pancreatic tumours (SPTP).

MATERIALS AND METHODS

This retrospective study analysed venous phase CT images of 39 patients with SPTP confirmed at surgery and histopathology and measured using the Ki-67 proliferation index from November 2015 to February 2022. According to the Ki-67 proliferation index, they were divided into high expression (Ki-67 ≥ 4%) and low expression (Ki-67 < 4%) groups. The histogram features of quantitative parameters were extracted using MaZda software, and the quantitative parameters of CT histograms were compared between groups. The receiver operating characteristic (ROC) curves of the patients were plotted according to the parameters, with statistically significant differences. The area under the curve (AUC), sensitivity, and specificity were calculated, and the effectiveness of the histogram parameters in predicting Ki-67 expression was analysed and evaluated.

RESULTS

In total, 27 SPTP patients were enrolled, including 11 with high expression of Ki-67 and 16 with low expression. Comparative analysis of the Ki-67 high- and low-expression groups revealed a statistically significant in necrosis and variance (p<0.05). ROC curve analysis showed that the AUC of necrosis and variance predicting Ki-67 expression status were 0.753 and 0.841, the sensitivities were 81.8% and 81.3%, and the specificities were 68.7% and 81.8%, respectively.

CONCLUSION

Preoperative CT histogram features help predict Ki-67 expression status in patients with SPTP.

Local resection for solid pseudopapillary neoplasms of the pancreas shows improved postoperative gastrointestinal function and reduced mental stress: a multiquestionnaire survey from a large cohort

BACKGROUND

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare, low-grade malignant pancreatic tumor with a highly favorable prognosis. Most SPN patients are young and middle-aged women. The main controversial topic for SPN is local resection (LR) versus radical resection (RR). Theoretically, LR could lead to better gastrointestinal function (GIF) and less mental stress. However, no data is available to support this hypothesis.

METHODS

All SPN patients undergoing surgical treatment in Peking Union Medical College Hospital from 2001 to 2021 were included in the study. A cross-sectional online multiquestionnaire survey containing 110 questions was sent to them (Clinicaltrial.org, NCT05604716). This online multiquestionnaire survey focused on GIF and mental stress and consisted of eight questionnaires. Multiple linear regression analysis was conducted to identify independent factors impacting GIF and mental stress.

RESULTS

A total of 183 cases provided valid results. Among them, 46 patients (25.1%) underwent LR, and 137 (74.9%) underwent RR. Ninety-four cases (51.4%) underwent minimally invasive surgery (MIS), while 89 (48.6%) underwent open surgery. The average GSRS score of the patients was 1.9±0.7, indicating that most suffered from mild gastrointestinal dysfunction. The scores of PHQ-9 and GAD-7 in 16 patients (8.7%) and 27 (14.8%) patients, respectively, were beyond 10.0, which indicated clinical depression and anxiety. Additionally, 19 (10.4%) patients reported poor ability to work, and 31(16.9%) patients had significant body image concerns. Compared to other clinicopathological characteristics, LR (LR vs. RR: PHQ-9 score, P =0.018; WAI average score, P =0.010; EORTC QLQ-C30, nine subdomains, P <0.05; GSRS average score, P =0.006) and MIS (MIS vs. open surgery: EORTC QLQ-C30, three subdomains, P <0.05; GSRS average score, P =0.006) were the most significant factors predicting improved GIF and reduced mental stress.

CONCLUSIONS

This study systematically presents postoperative GIF and mental stress of SPN patients using validated multiquestionnaires for the first time. It provides solid evidence that LR and MIS can improve GIF and reduce mental stress after surgery for SPN patients, which could be helpful for the surgeons to make more personalized surgical plans for their patients.

Solid Pseudopapillary Neoplasms of the Pancreas: Clinicopathologic Analysis and a Predictive Model

Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare. They are considered low-grade malignancies, and a small percentage of patients experience recurrence or metastasis. It is critical to investigate associated biological behavior and identify patients at a risk of relapse. This was a retrospective study of 486 patients with SPNs who were diagnosed between 2000 and 2021. Their clinicopathologic features, including 23 parameters and prognoses were analyzed. Six patients (1.2%) presented with synchronous liver metastasis. A total of 21 patients experienced recurrence or metastasis postoperatively. The overall and disease-specific survival rates were 99.8% and 100%, respectively. The 5- and 10-year relapse-free survival (RFS) rates were 97.4% and 90.2%, respectively. Tumor size, lymphovascular invasion, and the Ki-67 index were independent predictors of relapse. Furthermore, a Peking Union Medical College Hospital-SPN risk model was built to evaluate the risk of relapse and compared it with the American Joint Committee on Cancer tumor staging system (eighth edition, 2017). Risk factors included 3 parameters: tumor size (>9 cm), lymphovascular invasion status (presence), and Ki-67 index (>1%). Risk grades were available for 345 patients, who were divided into 2 groups: (1) low risk (n = 124) and (2) high risk (n = 221). The group with no risk factors was designated as low risk and had a 10-year RFS of 100%. The group associated with 1 to 3 factors was designated as high risk, with a 10-year RFS of 75.3%. Receiver operating characteristic curves were generated, and the area under the curve was 0.791 for our model and 0.630 for the American Joint Committee on Cancer with respect to the cancer staging system. We validated our model in independent cohorts and demonstrated a sensitivity of 98.3%. In conclusion, SPNs are low-grade malignant neoplasms that rarely metastasize, and the 3 selected pathologic parameters can be used to predict their behavior. A novel Peking Union Medical College Hospital-SPN risk model was proposed for routine application to guide the patient counseling in clinical practice.

PANCREATECTOMY AND HEPATECTOMY: A COMBINED SURGICAL RESECTION OF PSEUDOPAPILLARY SOLID TUMOR OF PANCREAS ASSOCIATED WITH HEPATIC METASTASIS

BACKGROUND

Solid pseudopapillary tumor of the pancreas has been frequently reported in the past two decades. Surgery remains the treatment of choice, with the liver being the most frequent site of metastases.

AIMS

The study aimed to present an option of surgical treatment for an 18-year-old female patient with a solid lesion in the body and tail of the pancreas associated with metastatic lesions in both hepatic lobes.

METHODS

Two surgical procedures were scheduled. In the first procedure, body-caudal pancreatectomy with splenectomy was performed, associated with the resection of three lesions of the liver's left lobe. A right hepatectomy was performed 6 months later, progressing without complications.

RESULTS

The patient continues without clinical complaints on the last return, and abdominal magnetic resonance performed 28 months after the second procedure does not show liver or abdominal cavity lesions.

CONCLUSIONS

The knowledge on the biological behavior of tumors, evolution, and recurrence risks allows the indication of more rational surgical techniques that best benefit patients.

Solid Pseudopapillary Neoplasms of the Pancreas Across Races Demonstrate Disparities with Comparably Good Prognosis

BACKGROUND

Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare with low-grade malignancy and unclarified clinicopathological features. This study aimed to examine their characteristics and re-evaluate current treatments.

METHODS

Databases from three sources were screened for patients with SPNs. We compared the perioperative variables, clinical data, overall survival (OS), and prognostic factors for recurrence among the three corresponding cohorts.

RESULTS

We identified 286 patients diagnosed with SPNs between 1988 and 2020. Patients were mostly women (81%; median age: 38 years), and peak incidence was observed in women of 20-29 years of age. SPNs had a peak incidence in Asian men at 50-59 years of age (p = 0.002) and a delayed peak incidence in Asian women at 30-39 years of age (p < 0.001). Treatment strategies differed significantly across the institutions and included variations in the number of harvested lymph nodes and rates of vascular resection. Lymph node positivity was the only predictor of postoperative recurrence (odds ratio, 2.2; 95% confidence interval, 1.38-2.99; p = 0.007). Higher rates of lymphovascular invasion (p = 0.02), perineural invasion (p < 0.001), and R1 margin involvement (p < 0.001), as seen in one institution, did not result in poorer long-term survival in terms of the overall (p = 0.43), SPN-specific (p = 0.69), and recurrence-free survivals (p = 0.067).

CONCLUSIONS

In contrast to previous findings that SPNs are prevalent in young women, a racial predilection for middle-aged Asian men and a delayed female peak incidence were noted. Parenchyma-preserving pancreatectomy may be an acceptable treatment. Non-radical surgery may be appropriate in patients with multiple comorbidities.

Analysis of invasiveness and tumor-associated macrophages infiltration in solid pseudopapillary tumors of pancreas

BACKGROUND

Solid pseudopapillary tumor (SPT) is a rare pancreatic tumor. Considering its malignant behaviors, SPT has been classified as a low-grade malignant tumor. Indeed, only 9.2% of all SPT patients are initially diagnosed as malignant with invasion or metastasis. Thus, one of the challenges in managing SPT patients is predicting malignant behavior.

AIM

To investigate the malignant behavior and tumor-associated macrophage (TAM) infiltration between different histopathologic features of SPT patients.

METHODS

Twenty-five formalin-fixed paraffin-embedded tissue samples from 22 patients pathologically diagnosed with an SPT between 2009 and 2019 at West China Hospital were included in this retrospective study. Integrity of the capsule and growth pattern of the tumor cells was assessed microscopically in hematoxylin-eosin (HE)-stained sections. Based on the histopathological features, the SPT patients were divided into two groups: capsule or invasion. Clinical features, malignant behavior, and TAM infiltration were compared between the two groups.

RESULTS

Among the 22 SPT patients, 11 were identified for each group, having either a capsule or invasion histopathologic feature. Malignant behavior was more frequent in the invasion group, including 2 patients who had peripheral organ invasion, 3 with liver metastasis, and 1 with both lymph node and spleen metastases (P= 0.045). Ki-67 index of more than 3% was also more frequent in the invasion group (P = 0.045). Immunohistochemical analysis showed that the invasion group had a significant increase of CD68-positive TAMs in intratumor and peritumor sites in comparison with the capsule group (all P < 0.0001). Similarly, CD163-positive M2-like macrophages were also markedly increased in the intratumor and peritumor sites in the invasion group (all P < 0.0001). At the liver metastasis site, both intratumor and peritumor tissues showed relatively high-level CD68-positive TAMs and CD163-positive M2-like macrophages infiltration. However, the differences between the intratumor, peritumor and normal hepatic tissues did not reach statistical significance (all P > 0.05).

CONCLUSION

SPT patients with invasion evident under microscope were more likely to exhibit malignant behavior and TAM infiltration, especially M2-like macrophages. This finding can help in future investigations of the underlying mechanism of TAM-mediated SPT malignant behavior.

Impact of parenchyma-preserving surgical methods on treating patients with solid pseudopapillary neoplasms: A retrospective study with a large sample size

BACKGROUND

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm that mainly affects young women.

AIM

To evaluate the impact of parenchyma-preserving surgical methods (PPMs, including enucleation and central pancreatectomy) in the treatment of SPN patients.

METHODS

From 2013 to 2019, patients who underwent pancreatectomy for SPNs were retrospectively reviewed. The baseline characteristics, intraoperative index, pathological outcomes, short-term complications and long-term follow-up data were compared between the PPM group and the conventional method (CM) group.

RESULTS

In total, 166 patients were included in this study. Of them, 33 patients (19.9%) underwent PPM. Most of the tumors (104/166, 62.7%) were found accidentally. Comparing the parameters between groups, the hospital stay d (12.35 vs 13.5 d, P = 0.49), total expense (44213 vs 54084 yuan, P = 0.21), operation duration (135 vs 120 min, P = 0.71), and intraoperative bleeding volume (200 vs 100 mL, P = 0.49) did not differ between groups. Regarding pathological outcomes, tumor size (45 vs 32 mm, P = 0.07), Ki67 index (P = 0.53), peripheral tissue invasion (11.3% vs 9.1%, P = 0.43) and positive margin status (7.5% vs 6%, P = 0.28) also did not differ between groups. Moreover, PPM did not increase the risk of severe postoperative pancreatic fistula (3.8% vs 3.0%, P = 0.85) or tumor recurrence (3.0% vs 6.0%, P = 0.39). However, the number of patients who had exocrine insufficiency during follow-up was significantly lower in the PPM group (21.8% vs 3%, P = 0.024). CM was identified as an independent risk factor for pancreatic exocrine insufficiency (odds ratio = 8.195, 95% confident interval: 1.067-62.93).

CONCLUSION

PPM for SPN appears to be feasible and safe for preserving the exocrine function of the pancreas.

The Sex Features of Patients With Solid Pseudopapillary Neoplasms of the Pancreas: A Retrospective Study

Background

Solid pseudopapillary neoplasms of the pancreas (SPNs) in male patients are more frequently reported. The aim of the study was to evaluate the sex features of SPN and the risk factors that predict tumor recurrence.

Methods

From 2013 to 2019, patients who were pathologically confirmed to have SPNs were retrospectively reviewed. The baseline study parameters were compared between males and females. A logistic regression model was established to identify the independent risk factors for tumor recurrence.

Results

In total, 221 patients were included in this study. Of them, 53 patients (24.0%) were males. Male patients were older than female patients (39.1 vs 31.6 years, P=0.001), and the tumor size in male patients was smaller than that in female patients (50.38 vs 39.65 mm, P=0.038). The preoperative imaging diagnostic accuracy was significantly higher in females than in males (70.5% vs 54%, P=0.02). SPNs in male patients tended to be misdiagnosed with other malignant tumors (37.7% vs 10.7%, P<0.0001), with a more solid component observed in images (66.8% vs 24.7%, P<0.0001). For immunohistochemical staining, the expression of beta catenin was significantly lower in male patients (P=0.002), and the expression of vimentin was the opposite (P=0.01). The overall survival rate and disease-free survival were not different. Based on multivariate analysis, older age [hazard ratio (HR)= 1.094, 95% confidence interval (CI): 1.005-1.190] and KI 67 index grade III (HR=12.029, 95% CI: 2.399-60.311) were independent risk factors for tumor recurrence.

Conclusion

The clinical and imaging features of SPN in males were not in full accord with those in females; however, the differences did not influence prognosis.

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.

Prediction of Recurrence Risk in Solid Pseudopapillary Neoplasm of the Pancreas: Single-Institution Experience

BACKGROUND

Solid pseudopapillary neoplasm (SPN) of the pancreas is a low-grade malignant neoplasm with unpredictable behavior. Factors associated with recurrence were not conclusively identified. The aim of this study is to define the clinicopathological criteria for recurrence risk prediction in SPNs based on the most recent scientific evidence and to present our experience with SPNs.

METHODS

A retrospective review of patients with SPNs operated on in our institution from June 2012 to June 2018 was completed. Patient characteristics and clinical outcomes were analyzed. A detailed literature review was performed to evaluate the factors associated with the recurrence of SPNs.

RESULTS

The cohort consisted of 13 female patients with a median age of 24 years and a mean tumor size of 7.7 cm. Body and tail (53.8%) were the most common location, and distal pancreatectomy with splenectomy was the prevalent surgical procedure. One patient of SPN operated on for local recurrence after 11 years which had high-grade malignant histological features on the previously resected tumor. At a median follow-up of 42 months (range 36 to 108), all patients were disease free and alive. The proposed criteria for predicting recurrence in SPNs include tumor size >8 cm, synchronous metastasis, malignant SPN (according to 2000 or 2010 World Health Organization [WHO] criteria), lymphovascular invasion, pancreatic parenchymal invasion, and high Ki-67 index (>4%). All these are worse prognostic factors and should be considered as high-risk factors for postoperative relapse.

CONCLUSION

The above-mentioned criteria can better predict SPN recurrence. Patients with high-risk features should undergo an extended follow-up.