Do Solid Pseudopapillary Neoplasms Shrink After Menopause?: Review of the Literature

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.

Spontaneous regression in solid pseudopapillary neoplasm of pancreas

A solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm that mainly occurs in young women. We herein report the case of spontaneous regression in SPN of the pancreas. A 48-years-old female was found to have a mass in the head of the pancreas on examination for her back pain and referred to our hospital in 20XX. Laboratory data showed no abnormalities in serum levels of pancreatic enzymes and tumor markers. A contrast CT scan of upper abdomen showed a slightly enhanced lesion (23 × 19 mm in diameter) without cystic component or fibrous capsule in the head of the pancreas. An MRI scan showed the mass as low-intensity in T1-WI and high-intensity in T2-WI. She admitted to our hospital for further examination of a pancreatic mass by EUS-FNA in 20XX + 4. EUS showed a slightly hypoechoic mass (30 × 19 mm in diameter) compared with the neighboring normal pancreas. Tumor margin was relatively clear and the internal echo image was homogenous. Histological findings revealed a solid and pseudopapillary proliferation of eosinophilic polygonal cells with oval nuclei. The tumor cells were positive for vimentin and CD10 in the cytoplasm and β-catenin in the nuclei, which led to the diagnosis of SPN. We recommended this patient to undergo surgical resection, however, the patient chose follow-up examinations. Follow-up study after 1 year using MRI scan showed spontaneous regression, which was coincided with her menopause. These findings suggest that the natural regression of SPN may occur and female sex hormone changes may regulate the growth of SPN.

Pancreatic Solid Pseudopapillary Neoplasm: Key Pathologic and Genetic Features

CONTEXT.—

Solid pseudopapillary neoplasm of the pancreas is a low-grade malignant tumor generally associated with a good prognosis. Solid pseudopapillary neoplasms show peculiar morphologic features, but sometimes the differential diagnosis with other pancreatic neoplasms (ie, pancreatic neuroendocrine tumors) can be a challenging task, especially in cytologic or biopsy specimens. In these cases immunohistochemistry is a useful tool, but the diagnostic utility of several proposed immunohistochemical markers is questionable. In recent years, despite several attempts to characterize the pathogenetic, molecular, and prognostic features of solid pseudopapillary neoplasms, they still remain unclear.

OBJECTIVE.—

To give the reader a comprehensive update on this entity.

DATA SOURCES.—

The PubMed database (US National Library of Medicine) was searched using the following string: pseudopapillary tumor [AND/OR] neoplasm [AND/OR] pancreas. All articles written in English were included. In addition, because a heterogeneous terminology has been used in the past to define solid pseudopapillary neoplasms, the reference lists of each paper selected in the PubMed database were also reviewed.

CONCLUSIONS.—

This review gives a comprehensive update on the pathologic, clinical, and molecular features of solid pseudopapillary neoplasms, particularly addressing issues and challenges related to diagnosis. In addition, we have tried to correlate the molecular alterations with the morphologic and clinical features.

Sex Differences in the Exocrine Pancreas and Associated Diseases

Differences in pancreatic anatomy, size, and function exist in men and women. The anatomical differences could contribute to the increase in complications associated with pancreatic surgery in women. Although diagnostic criteria for pancreatitis are the same in men and women, major sex differences in etiology are reported. Alcohol and tobacco predominate in men, whereas idiopathic and obstructive etiologies predominate in women. Circulating levels of estrogens, progesterone, and androgens contribute significantly to overall health outcomes; premenopausal women have lower prevalence of cardiovascular and pancreatic diseases suggesting protective effects of estrogens, whereas androgens promote growth of normal and cancerous cells. Sex chromosomes and gonadal and nongonadal hormones together determine an individual's sex, which is distinct from gender or gender identity. Human pancreatic disease etiology, outcomes, and sex-specific mechanisms are largely unknown. In rodents of both sexes, glucocorticoids and estrogens from the adrenal glands influence pancreatic secretion and acinar cell zymogen granule numbers. Lack of corticotropin-releasing factor receptor 2 function, a G protein-coupled receptor whose expression is regulated by both estrogens and glucocorticoids, causes sex-specific changes in pancreatic histopathology, zymogen granule numbers, and endoplasmic reticulum ultrastructure changes in acute pancreatitis model. Here, we review existing literature on sex differences in the normal exocrine pancreas and mechanisms that operate at homeostasis and diseased states in both sexes. Finally, we review pregnancy-related pancreatic diseases and discuss the effects of sex differences on proposed treatments in pancreatic disease.