Scrotal PNET in an Adult Patient

Scrotal PNET in an adult PatientTITLE Scrotal PNET in an Adult Patient Radiologic-Pathologic Correlation.AUTHORSM Gabriela Tirapu-de-Sagrario, Sandra Baleato-Gonzlez, Elena Pintos-Martnez and Roberto Garca-FigueirasKEY WORDSNeuroectodermal Tumors, Scrotum, Sarcoma, Groin, Inguinal CanalINTRODUCTIONWe report a, histologically confirmed, r be case of a off-base primitive neuroectodermal tumour (pPNET) originating from the scrotal sac in an adult patient. This report emphasizes the important role of pathology examination to reach final diagnosis on the basis of immunohistochemistry and negatronic microscopy findings. terminus depends upon the localization and staging of the tumour, age of the patient, histologic classification, extent of surgical resection and time to treatment.CASE REPORTAn 84-year-old man was admitted to our hospital with an inguinoscrotal, irreducible, painless stilt with a large(p) consistency, which had progressed over the last six months. There was no prese nce of urinary or intestinal symptoms. Alpha-Fetoprotein, beta-HCG and LDH values were found to be expression. The patient was subsequently referred to the urology Departament and he underwent a pelvic MRI. It confirmed a 12x11x19 cm solid mass, which demonstrated central areas of necrosis and subtle amounts of haemorrhage (Figure 1). This mass demonstrated tag and heterogeneous enhancement after intravenous gadolinium administration as well as evidence of internal vascular flow. Both testes showed a normal morphology and signal on T2-weighted sequences (Figure 1). Surgical excision was performed by the Urology Service and they reported that the spermatic electric cord, femoral vessels and testes were displaced but not infiltrated by the mass (Figure 2A). Despite the fact that a sarcoma was the suggested diagnosis on imaging, this case exhibited microscopic pathology features of a rare pPNET tumour in an unexpected location. The presence of neurosecretory granules in the electr on microscopy (Figure 3) and the EWS-FLI1 traslocation confirmed the diagnosis.DISCUSSIONpPNET is an uncommon tumor that belongs to the Ewings Sarcoma family of tumors (1-4). It is an aggressive neoplasm, with large size at presentment, which metastasizes rapidly and predominantly affects children and adolescents (1,3,5).The most common locations are the tit wall, paraspinal area in the chest, abdomen and pelvis (7,8). Ellinger J, et al (1), performed a MEDLINE search identifying renal, bladder, prostate, ureter and seminal cord PNETs, Hari S et al (3) and Kim MS et al (9) also depict kidney and retroperitoneum cases and even an uterus case was described by Peres E et al (10) but, to our knowledge, this is the first pPNET case which originated in the scrotal sac, independent of any organ. This tumor is exceedingly rare in adults and the clinical findings (large painful mass) do not help to distinguish a benign from a malignant tumor (11). At the presentation most of them grow a s scrotal masses rather than inguinal masses because they usually originate just below the external inguinal sonority (12).PNET tumor shows no specific imaging features, but radiological studies are useful to rule out other possible etiologies, to define the location of the tumor and its morphological characteristics as well as its distance extension (1,3,4). In order to diagnose PNET, and differentiate it from other tumors of the Ewing family, we need to demonstrate the expression of virtually neural markers on the inmunohistochemical stains, including neurofilament, NSE, Leu-7, vimentin, S-100, CD-56, chromogranin and synaptophysin (2). A definitive finding is the EWS-FLI1 traslocation and the presence of neurosecretory granules in electron microscopy (7,8).In conclusion, we present a histologically confirmed case of an extratesticular peripheral scrotal PNET, which possibly originated from a remnant of neuroectodermic cells of the neural crest. In a case like this one, with a h uge genital mass, ultrasound and MRI are very useful modalities to assess the location of the mass, its dependency on any other organ and the tumoral internal structure. These will help us to suggest a possible differential diagnosis however the definitive diagnosis requires histopathological and immunohistochemical examination.REFERENCESEllinger J, Bastian PJ, Hauser S, et al. uninstructed Neuroectodermal Tumor Rare, highly aggressive differential diagnosis in Urologic Malignancies. J Urol 2006 68(2)257-262Gurung P,Attar K andPeters J. Primitive neuroectodermal tumorof thespermatic cord. Int J Urol.2010 Jul17(7)679-80.Hari S,Jain TP,Thulkar S, et al. Imagingfeaturesofperipheral primitive neuroectodermal tumours. Br J Radiol.2008 Dec81(972)975-83.Javery O,Krajewski K,ORegan K,el al. A to Z of extraskeletal Ewing sarcoma family of tumors in adults imaging features of primary disease, metastatic patterns, and treatment responses. AJR Am J Roentgenol.2011 Dec197(6)W1015-22.Ibarburen C , Haberman JJ, Zerhouni EA. Peripheral primitive neuroectodermal tumors. CT and MRI evaluation. Eur J Radiol. 1996 Feb21(3)225-32.Fontaine C,Schots R,Braeckman J, et al. Long-term survival in an adult metastatic renal peripheral primitive neuroectodermal tumor (PPNET) with multimodality treatment including high-dose chemotherapy. Ann Oncol.1997 Jul8(7)691-4.Khong P.L, Chan G.C.F, Shek T.W.H, et al. Imaging of Peripheral PNET Common and uncommon locations. Clinical Radiology. 200257272-277Hoffer FA, Gianturco LE, Fletcher JA, et al. Percutaneous Biopsy of Peripheral Primitive Neuroectodermal Tumors and Ewings Sarcomas for Cytogenetic Analysis. AJR. 19941621141-1142Kim MS, Kim B, Park CS, et al. Radiologic Findings of Peripheral Primitive Neuroectodermal Tumor Arising in the Retroperitoneum. AJR. 2006 1861125-1132.Peres E, Mattoo TK, Poulik J, et al. Primitive Neuroectodermal Tumor (PNET) of the Uterus in a Renal Allograft Patient A Case Report. Pediatr Blood Cancer. 200544283-285.Lio e TF and Biggart JD. Tumours of the spermous Cord and Paratesticular Tissue. A Clinicopathological Study. British Journal of Urology. 1993 71600-606Rodrguez D and Olumi AF. Management of spermatic cord tumors a rare urologic malignancy. Ther Av Urol. 2012 4(6) 325-334FIGURE LEGENDSFigure 1A) Axial T2 TSE shows a large heterogenous inguinoscrotal mass that displaces the penis (void arrows) but apparently not infiltrates it. B) Axial T1 after intravenous contrast Maximum copulation enhancement. It shows central hypoperfusion (black arrows), which is hyperintense on T2 sequences, probably due to necrosis or hemorrhage, and a solid hypervascularized periphery (white arrows).Figure 2A) Surgical photograph shows the spermatic cord (white arrows), which is displaced but not affected by the large mass. B) A long axis section of the mass. Its observed an heterogenous tumor of mottled appearance with partly embossed, clear brownish areas, which are the solid ones (black asterisks). It also has extensive necrotic and hemorrhagic component (white asterisks).Figure 3Electronic Microscopy. The presence of neuroendocrine granules (white circles) of miscellaneous sizes (from 80 to 120 nm) in the cytoplasm of the tumor cells is confirmed. This finding demonstrates the neuroendocrine differentiation of the neuroectodermal tumor.