Solid pseudopapillary tumor of the pancreas (SPPT): Still an unsolved enigma

Abstract

Solid pseudo-papillary tumor (SPPT) is a rare cystic tumor of the pancreas (1-3% of exocrine tumors of the pancreas) which shows an "enigmatic" behavior on the clinical and molecular pattern. A retrospective analysis of the citological studies and resected specimens of pancreatic cystic tumors from May 1996 to February 2010 was carried out. Three cases of SPPT were found, which are the objective of this study. The diagnosis was established upon occasional finding in the abdominal CT, in spite of sizing between 3 and 6 cm of diameter. In the three cases the preoperative diagnosis was confirmed by citology and specific immunohistochemical staining. Cases 2 and 3 showed strong immunoreactivity for Beta-Catenina and E-Cadherina staining. Radical resection (R0) was carried out in the three cases. A young male -21 years of age (case 1)-who had duodenal infiltration and two lymph nodes metastases died of hepatic and peritoneal recurrence 20 months following surgery. The other two cases are free of disease. The current review of the literature reports roughly 800 cases since the first report in 1959, and shows the enigmatic character of this tumor regarding the cellular origin, molecular pathways, prognostic factors and clinical behavior.Key words: Solid-pseudopapillary tumor. Pancreatic cystic neoplasm. Prognosis. Beta-catenina. RESUMENEl tumor pseudopapilar (TSPP) es un tumor quístico del pán-creas muy poco frecuente (1-3% de los tumores exocrinos del páncreas) y que tiene un comportamiento oncológico y molecular "enigmático". Se realizó un análisis retrospectivo de las citologías de las lesiones quísticas del páncreas, así como de los tumores quísticos resecados entre mayo de 1996 y febrero de 2010, encontrándose tres tumores SSPP, motivo de este estudio. En los tres casos el diagnóstico fue ocasional en el TC abdominal a pesar de presentar unos tamaños entre 3 y 6 cm de diámetro. En los tres casos se confirmó el diagnóstico preoperatorio mediante citología e inmunohistoquímica. En los casos 2 y 3 se confirmó la positividad para Beta-Catenina y E-Cadherina. En todos los casos se realizó cirugía radical (R0). Un varón de 21 años -caso 1-que presentaba infiltración duodenal y metástasis ganglionares falleció de progresión hepática y peritoneal a los veinte meses de la cirugía. Las otras dos pacientes -casos 2 y 3-se encuentran libres de recidiva. La revisión de la literatura desde su descripción en 1959 hasta la actualidad -aproximadamente 800 casos-confirma el carácter enigmático de este tumor en relación a su origen celular, molecular, factores pronósticos y comportamiento clínico.Palabras clave: Tumor sólido-pseudopapilar, Tumores quísti-cos de páncreas. Pronóstico.

Solid-Pseudopapillary Neoplasm of the Pancreas: Cytomorphologic Findings and Literature Review

“…[8,9,29]. A few studies have suggested a poor prognosis in males; however, larger studies have disputed this association [2,5,7,8,15,16,22,30,31]. Also, the malignant potential of SPN found in children is not significantly different from that in adults [29].…”

“…The predilection for female patients has led to conjectures about the origin of SPN. Some have suggested origin in ovarian tissue deposited in the pancreas during early embryogenesis [5,6]. In the largest meta-analysis to date, 2,744 cases of SPN reported in English language over 50 years (1961-2012) were analyzed, and the results demonstrated an overwhelming majority of female patients (87.8%), with a mean age of 28.5 years at presentation [7].…”

“…Degenerative changes may cause profound nuclear atypia; however, mitosis is rare [3]. Although SPNs are considered neoplasms of low malignant potential, more aggressive dedifferentiated (sarcomatous) variants have been reported [5,8,15,21]. …”

Solid-pseudopapillary tumor of pancreas in a young woman: a case report and literature review

“…Solid-pseudopapillary tumor of pancreas can be visualized in many imaging modalities, such as ultrasonography (US), X-ray computed tomography (CT) and magnetic resonance imaging, which can be used to differentiate it from other pancreatic lesions 1,2,4,[15][16][17][18] .…”

“…Complete resection is curative in most cases 9,15,19 , but prognostic factors are not well established and clinical evolution cannot be predicted. Rare cases of fatal metastasizing solid-pseudopapillary tumors of pancreas have been previously reported, suggesting that these tumors may occasionally show aggressive clinical behavior 2,9,14,20 . In this article, we present a case of a SPT in a 17-year-old Brazilian woman with a good evolution.…”