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 neoplasms, Scrotum, Sarcoma, Groin, inguinal CanalINTRODUCTIONWe report a, histologically confirmed, obsolescent crusade of a marginal primitive neuroectodermal tumour (pPNET) originating from the scrotal sac in an vainglorious patient. This report emphasizes the important role of pathology examination to reach final diagnosing on the basis of immunohistochemistry and electronic microscopy findings. Outcome depends upon the localization and staging of the tumour, time of the patient, histologic classification, extent of surgical resection and time to treatment.CASE REPORTAn 84-year-old humanness was admitted to our hospital with an inguinoscrotal, irreducible, painless mass with a hard consistency, which had progressed over the suffer six m onths. There was no carriage of urinary or enteral symptoms. Alpha-Fetoprotein, beta-HCG and LDH values were found to be normal. The patient was subsequently referred to the Urology Departament and he underwent a pelvic MRI. It confirmed a 12x11x19 cm self-coloured mass, which exhibit aboriginal areas of necrosis and subtle amounts of haemorrhage (Figure 1). This mass demonstrated label 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 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 neoplasm in an unanticipated location. The presence of neurosecreto ry granules in the electron microscopy (Figure 3) and the EWS-FLI1 traslocation confirmed the diagnosis.DISCUSSIONpPNET is an unmatched tumor that be languishs to the Ewings Sarcoma family of tumors (1-4). It is an aggressive neoplasm, with large size at show, which metastasizes rapidly and predominantly affects children and adolescents (1,3,5).The most common locations are the chest wall, paraspinal area in the chest, breadbasket 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 described 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 pipe organ. This tumor is extremely rare in adults and the clinical findings (large painful mass) do not help to make a benign from a malignant tumor (11). At the pre sentation most of them grow as scrotal masses rather than inguinal masses because they usually originate just below the external inguinal ring (12).PNET tumor shows no specific imaging features, but radiological studies are profitable to rule out other realizable etiologies, to set apart the location of the tumor and its morphological characteristics as well as its hold extension (1,3,4). In order to diagnose PNET, and differentiate it from other tumors of the Ewing family, we guide to demonstrate the expression of some neural markers on the inmunohistochemical stains, including neurofilament, NSE, Leu-7, vimentin, S-100, CD-56, chromogranin and synaptophysin (2). A authoritative 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 huge 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. Primitive Neuroectodermal tumour 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.201 1 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 cytogenetical 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. Pedia tr Blood Cancer. 200544283-285.Lioe TF and Biggart JD. Tumours of the Spermatic 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 relative 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 visual aspect with partially embossed, clear brownish areas, which are the solid ones (black asterisks). It also has large necrotic and hemorrhagic component (white asterisks).Figure 3Electronic Microscopy. The presence of neuroendocrine granules (white circles) of various 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.