Journal of Postgraduate Medicine
 Open access journal indexed with Index Medicus & EMBASE  
     Home | Subscribe | Feedback  

CASE REPORT
[Download PDF
 
Year : 2015  |  Volume : 61  |  Issue : 2  |  Page : 126-128  

Primary renal primitive neuroectodermal tumor: A rare presentation

V Goel1, V Talwar1, C Dodagoudar1, S Singh1, A Sharma2, N Patnaik3,  
1 Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Center, New Delhi, India
2 Department of Pathology, Rajiv Gandhi Cancer Institute and Research Center, New Delhi, India
3 Department of Pathology, University College of Medical Sciences and Guru Tegh Bahadur Hospital, New Delhi, India

Correspondence Address:
V Goel
Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Center, New Delhi
India

Abstract

Primitive Neuroectodermal Tumor of the kidney is a rare entity. Very few cases of primary renal PNET have been reported to date. Most literature about rPNET is isolated case reports. We report a case of rPNET in a 39-year-old male with a pre-operative diagnosis of renal cell carcinoma with renal vein thrombosis. The patient underwent radical nephrectomy with thrombolectomy, and histopathological examination revealed a highly aggressive tumor composed of monotonous sheets of round cells. Tumor cells were positive for CD 99 and FLI-1, hence confirming the diagnosis of Primitive Neuroectodermal Tumor. Post-surgery, patient was given VAC/IE-based adjuvant chemotherapy. In view of highly aggressive nature of this tumor, prompt diagnosis and imparting effective chemotherapy regimen to the patient is required, and it is important to differentiate PNET from other small round-cell tumors because of different therapeutic approach.



How to cite this article:
Goel V, Talwar V, Dodagoudar C, Singh S, Sharma A, Patnaik N. Primary renal primitive neuroectodermal tumor: A rare presentation.J Postgrad Med 2015;61:126-128


How to cite this URL:
Goel V, Talwar V, Dodagoudar C, Singh S, Sharma A, Patnaik N. Primary renal primitive neuroectodermal tumor: A rare presentation. J Postgrad Med [serial online] 2015 [cited 2022 Oct 2 ];61:126-128
Available from: https://www.jpgmonline.com/text.asp?2015/61/2/126/150897


Full Text

 Introduction



Primitive Neuroectodermal Tumor (PNET), a highly aggressive tumor of the kidney is a rare malignancy with only few cases being reported in literature. [1] It generally occurs in adolescents and young adults with isolated pediatric cases. [2],[3] Boys and men are more likely to suffer rPNET (renal PNET), and the sex ratio (male: female) is about 3:1. [4] It usually presents at an advanced stage, with distant metastasis and is associated with a poor prognosis. We report in this paper, a case of primary renal PNET in a young male.

 Case Report



A 39-year-old male presented with complaints of hematuria and heaviness in the right flank since 15 days. Physical examination revealed a soft lump in the right hypochondrium. Ultrasound examination of the abdomen showed an irregular cystic structure in the right kidney at lower pole with few internal echoes. Size of the mass lesion was 25 × 30 mm. CT scan of the abdomen demonstrated a large significantly enhancing right renal lower polar mass with necrosis with thrombosis in right renal vein. On the basis of these clinico-radiological findings, diagnosis of right side renal cell cancer was made, and right radical nephrectomy with thrombolectomy was performed. Gross examination revealed a friable, grayish-white, lobulated mass (7 × 5 cm) with multiple foci of hemorrhage and necrosis. The mass extended from mid to lower pole of the right kidney and infiltrated into the renal pelvis and was limited to the renal capsule The renal vein and ureter were free of the tumor. There was a thrombus inside the renal vein, which was not adherent to intima of renal vein. No lymph nodes were dissected from aortocaval region. Microscopically, the tumor was composed of monotonous sheets of round cells with scant cytoplasm, hyperchromatic vesicular nuclei, coarse chromatin and few conspicuous nucleoli, transverse by thin fibrous bands infiltrating and entrapping the renal glomeruli and tubules [Figure 1]. Brisk mitosis and apoptosis was noted. Areas of necrosis were present. Lympho-vascular embolization was present. No extension into the peri-renal fat was seen. On immunohistochemistry, the tumor cells were positive for CD99 [Figure 2]a], FLI-1 [Figure 2]b], NSE [Figure 2]c], and synaptophysin [Figure 2]d], but negative for desmin, CK, EMA, and LCA. A diagnosis of PNET was made based on the above findings, and patient was started on VAC (vincristine, adriamycin, and cyclophosphamide) alternating with IE (ifosfamide and etoposide)-based adjuvant chemotherapy regimen which he tolerated well. After 6 cycles of chemotherapy, a PET scan showed absence of any metabolically active focal uptake in whole body. Bone marrow aspiration and biopsy was done, which revealed uninvolved bone marrow. Chemotherapy with VAC (vincristine, actinomycin D, and cyclophosphamide) alternating with IE (ifosfamide and etoposide) for a year was planned. {Figure 1}{Figure 2}

 Discussion



The Primitive Neuroectodermal Tumor (PNET), was first recognized by Arthur Purdy Stout in 1918, and is a member of the family of "small round-cell tumors." [5] PNET arising in the kidney was first reported by Mor in 1994. [6] Primitive Neuroectodermal Tumors occurs preferentially in the soft-tissues of the paravertebral region and chest wall, less frequently in extremities, with a slight male predominance. rPNET appears to be an unique clinical entity that behaves more aggressively than PNET arising at other sites. [7]

The presenting symptoms and images of rPNET are non-specific and similar to other renal tumors. rPNET show a male predominance with 85% cases being diagnosed during the second to fourth decade. It is an aggressive tumor that tends to recur locally and to metastasize to lymph nodes, lung, liver, bone, and bone marrow, which entail a worse prognosis. [8]

The differential diagnosis of rPNET includes other small round cell tumors like neuroblastoma, adult nephroblastoma, malignant lymphoma, rhabdoid tumor, small cell carcinoma and monophasic, poorly differentiated, round cell variant of synovial sarcoma, carcinoid, rhabdomyosarcoma, clear cell sarcoma of the kidney, the small cell variant of osteosarcoma, and desmoplastic small round cell tumor. [9]

Grossly, rPNET are typically very large tumors with about 65% measuring >10 cm in diameter. [10] They tend to be grayish in color, encapsulated, and contain focal areas of hemorrhage or necrosis. Microscopically, the tumor is composed of sheets of round cells; individual cells have a round nucleus with a distinct nuclear membrane, fine powdery chromatin, and 1 or 2 small nucleoli. The cytoplasm is ill-defined, scanty, usually PAS-positive, and mitosis are variable. Perivascular pseudo rosettes and Homer-Wright rosettes are common.

To better address the diagnosis, an immunohistochemical analysis is necessary. Immunohistochemical markers to be used to confirm diagnosis are cytokeratin (for nephroblastoma, small cell carcinoma, and synovial sarcoma), LCA (for Lymphoma), NSE/chromogranin A (for neuroblastoma), and CD-99 for PNET. CD99 (the product of MIC2 gene) greatly aids in recognizing the ES/PNET family of tumors. [11] Many PNET also stain for neural markers, including NSE, Leu-7, S-100 protein, synaptophysin, and PGP9.5. [12]

The most frequent translocation in PNET is t(11;22)(q24;q12), detected in approximately 90% of cases, resulting in EWS-FLI fusion gene. Monoclonal antibodies to FLI1 can be used to detect these tumors. [13]

The 5-year disease-free survival rate of rPNET is about 45% to 55%. [14] The overall survival in patients who had localized rPENT was longer than that in the patients who had rPENT with regional nodes or distant metastases. [15] The preferred treatment for rPENT is surgical resection associated with chemotherapy and radiotherapy treatment. The role of radiotherapy is not clear, but it may be advocated in locally advanced disease and involvement of Gerota's fascia. [15] Post-operative chemotherapy for rPENT is usually used and can improve the prognosis of rPNET. [7] The most commonly used chemotherapeutics are adriamycin, etoposide, dactinomycin, vincristine, cyclophosphamide, and ifosfamide. [7],[14] A multimodality management is recommended.

References

1Funahashi Y, Hattori R, Yamamoto T, Mizutani K, Yoshino Y, Matsukawa Y, et al. Ewing's sarcoma/primitive neuroectodermal tumor of the kidney. AktuelleUrol 2009;40:247-9.
2Citak EC, Oguz A, Karadeniz C, Okur A, Akyurek N. Primitive neuroectodermal tumor of the kidney in a child. Pediatr Hematol Oncol 2009;26:481-6.
3Popov SD, Sebire NJ, Pritchard-Jones K, Vujaniæ GM. Renal tumors in children aged 10-16 years: A report from the United Kingdom Children's Cancer and Leukaemia Group. Pediatr Dev Pathol 2011;14:189-93.
4Rodriguez-Galindo C, Marina NM, Fletcher BD, Parham DM, Bodner SM, Meyer WH. Is primitive neuroectodermal tumor of the kidney a distinct entity?Cancer 1997;79:2243-50.
5Stout AP. A tumor of the ulnar nerve. Proc NY Pathol Soc 1918;18:2-12.
6Mor Y, Nass D, Raviv G, Neumann Y, Nativ O, Goldwasser B. Malignant peripheral primitive neuroectodermal tumor (PNET) of the kidney. Med PediatrOncol 1994;23:437-40.
7Ohgaki K, Horiuchi K, Mizutani S, Sato M, Kondo Y. Primary Ewing's sarcoma/primitive neuroectodermal tumor of the kidney that responded to low-dose chemotherapy with ifosfamide, etoposide, and doxorubicin. Int J ClinOncol 2010;15:210-4.
8Aghili M, Rafiei E, Mojahed M, Zare M. Renal primitive neuroectodermal tumor: Does age at diagnosis impact outcomes? Rare Tumors 2012;4:e15.
9Friedrichs N, Vorreuther R, Poremba C, Schafer KL, Böcking A, Buettner R, et al. Primitive neuroectodermal tumor (PNET) inthe differential diagnosis of malignant kidney tumors. PatholRes Pract 2002;198:563-9.
10Eble JN, Sauter G, Epstein JI, Sesterhenn IA. World Health Organisation classification of tumors.Pathology and genetics of tumors of the urinary system and male genital organs.Lyon: IARC Press; 2004.
11Folpe AL, Goldblum JR, Rubin BP, Shehata BM, Liu W, Dei Tos AP, et al. Morphologic and immunophenotypic diversity in Ewing family tumors: A study of 66 genetically confirmed cases. Am J SurgPathol 2005;29:1025-33.
12Carter RL, Al-Sams SZ, Corbett RP, Clinton S. A comparative study of immunohistochemical staining for neuron-specific enolase, protein gene product 9.5 and S-100 protein in neuroblastoma, Ewing's sarcoma and other round cell tumors in children. Histopathology 1990;16:461-7.
13Rossi S, Orvieto E, Furlanetto A, Laurino L, Ninfo V, Dei Tos AP. Utility of the immunohistochemical detection of FLI-1 expression in round cell and vascular neoplasm using a monoclonal antibody. ModPathol 2004;17:547-52.
14Habermann H, Benesch M, Schips L, Pummer K, Ratschek M, Uggowitzer MM, et al. Findings and clinical course of a localized primitive peripheral neuroectodermal tumor of the kidney. UrolInt 2003;71:319-21.
15Thyavihally YB, Tongaonkar HB, Gupta S, Kurkure PA, Amare P, Muckaden MA, et al. Primitive neuroectodermal tumor of the kidney: A single institute series of 16 patients. Urology 2008;71:292-6.

 
Sunday, October 2, 2022
 Site Map | Home | Contact Us | Feedback | Copyright  and disclaimer