Primitive neuroectodermal tumors

Ambros, I. M., Ambron, P. F., and Strehl, S. (1991) M1C2 is a specific marker for Ewing s sarcoma and peripheral primitive neuroectodermal tumors. Cancer 67, 1886-1893. 

Brustle O, Ohgaki H, Schmitt HP, Walter GF, Ostertag H, Kleihues P (1992) Primitive neuroectodermal tumors after prophylactic central nervous system irradiation in children. Association with an activated K-ras gene. Cancer, 69 2385-2392. 

Hasegawa T, Hirose T, Ayala AG, Ito S, Tomaru U, Matsuno Y, et al. Adult neuroblastoma of the retroperitoneum and abdomen dinicopathologic distinction from primitive neuroectodermal tumor. Am J Surg Pathol 2001 25 918-24. 

Qian X, Jin L, Shearer BM, et al. Molecular diagnosis of Ewing s sarcoma/primitive neuroectodermal tumor in formalin-fixed paraffin-embedded tissues by RT-PCR and fluorescence in situ hybridization. Diagn Mol Pathol. 2005 14 23-28. 

Fetal fibroblasts myometrium vascular smooth muscle fetal myocardium vascular endothelial cells selected reticulum cells of lymphatic organs some CD30+ lymphoid cells (rarely) selected leiomyosarcomas, epithelioid hemangioendotheliomas, epithelioid angiosarcomas, primitive neuroectodermal tumors and Ewing s sarcomas, malignant peripheral nerve sheath tumors, and clear cell sarcomas... 

Myometrium fetal myocardium selected neoplastic myeloid cells some leiomyosarcomas rare primitive neuroectodermal tumors and Ewing s sarcomas... 

Anti-CD99 (M) Dako 1 20 MWER Recognition of virtually all primitive neuroectodermal tumors and Ewing s sarcomas labels roughly 50% of synovial sarcomas and malignant peripheral nerve sheath tumors also present in lymphoblastic lymphomas/ leukemias presenting in soft tissue... 

The best-known association between FEI-1 and human tumors relates to its fusion with the EWS gene on chromosome 22 (22ql2) in many examples of Ewing s sarcoma/ primitive neuroectodermal tumor (PNET).i An associated fusion protein results from that event, which probably plays a role in the evasion of cellular senescence. 

FIGURE 4.14 Nuclear staining for FEI-1 protein in primitive neuroectodermal tumor. 

Parham DM, Dias P, Kelly DR, et al. Desmin positivity in primitive neuroectodermal tumors of childhood. Am J Surg Pathol. 1992 16 483-492. 

Gardner LJ, Polski JM, Fallon R, et al. Identification of CD56 and CD57 by flow cytometry in Ewing s sarcoma or primitive neuroectodermal tumor. Virchows Arch A. 1998 433 35-40. 

Eolpe AL, Schmidt RA, Ghapman D, et al. Poorly differentiated synovial sarcoma immunohistochemical distinction from primitive neuroectodermal tumors and high-grade malignant peripheral nerve sheath tumors. Am J Surg Pathol. 1998 22 673-6S2. 

Folpe AL, Hill CE, Patham DM, O Shea PA, Weiss SW. Immunohistochemical detection of FLI-1 protein expression A study of 132 round-cell tumors with emphasis on GD99-positive mimics of Ewing s sarcoma/primitive neuroectodermal tumor. Am J Surg Pathol. 2000 24 1657-1662. 

Masui F, Matsuno Y, Yokoyama R, et al. Synovial sarcoma, histologically mimicking primitive neuroectodermal tumor/Ew-ing s sarcoma at distant sites. ]pn J Clin Oncol. 1999 29 438-441. 

The ability of melanoma to simulate the appearance of various soft tissue sarcomas is also well documented. These include malignant peripheral nerve sheath tumors, gastrointestinal stromal tumors, epithelioid angiosarcoma, rhabdoid tumors, osteosarcomas, and primitive neuroectodermal tumors, to name a few. The detailed immunophenotypic properties of those lesions are provided elsewhere in this book. However, none of them manifests reactivity for gplOO-related melanocytic markers or tyrosinase, making those markers essential to the differential diagnostic process. 

EM, extramammary EWS, Ewing s sarcoma FISH, fluorescent in situ hybridization Gl, gastrointestinal IHC, immunohistochemistry PNET, primitive neuroectodermal tumor. 

Vakar-Lopez F, Ayala AG, Raymond AK, Czerniak B. Epithelial phenotype in Ewing s sarcoma/primitive neuroectodermal tumor. Int J Surg Pathol. 2000 8 59-65. 

Jones JE, and McGill T. Peripheral primitive neuroectodermal tumors of the head and neck. Arch Otolaryngol Head Neck Surg. 1392 121(12) 1392-1395. 

Neuroblastomas are small, round, blue cell tumors that may arise in the adrenal gland and a variety of extra-adrenal sites. The differential diagnosis is wide and includes rhabdomyosarcoma, Ewing s sarcoma-primitive neuroectodermal tumor (ES-PNET), medulloblastoma, small cell osteosarcoma, lymphoblastic lymphoma, blastematous Wilms tumor, and small cell desmoplastic tumor. Numerous markers have been used for the diagnosis of neuroblastomas including NE markers, cytoskeletal proteins, catecholamine-synthesizing enzymes, and neuroblastoma-"specific antibodies (Eig. 

CD99 is a useful marker for the distinction of neuroblastomas from other small, round, blue cell tumors. More than 100 cases of neuroblastoma have now been studied for CD99, and all have been negative. In contrast, nearly 100% of cases of Ewing s sarcoma-primitive neuroectodermal tumor (ES-PNET) are CD99-positive. Anti-Pi-microglobulin is another marker that is negative in neuroblastoma but positive in approximately 75% of ES-PNET. ... 

The primitive neuroectodermal tumor (PNET) may rarely occur in the mediastinum, either in the anterior or in the posterior compartments. The immunophe-notype of PNET is similar to that of neuroblastoma, but the former of these lesions shows more uniform reactivity for vimentin and only occasionally is labeled for neurofilament protein." Moreover, the CD99 (p30/32 [MIC-2]) and MB2 antigens and beta-... 

FIGURE 11.6 Markers of interest in the differential diagnosis of primitive neuroectodermal tumor (PNET) versus small-cell neuroendocrine carcinoma of the mediastinum (SCNC). 

FIGURE 11.11 Labeling for CD99 (MIC-2) (A) in primitive neuroectodermal tumor of the mediastinum (B). 

In addition to the small-cell tumors presented in the foregoing sections, others of a metastatic nature also may involve the mediastinum. These include small-cell osteosarcoma and Ewing s sarcoma/primitive neuroectodermal tumor (PNET) of bone, as well as small-cell malignant melanoma. Except for the last of these possibilities, the primary lesion in such cases is typically obvious and there is no question of whether the intra-thoracic neoplasm might have arisen there. Nonetheless, melanomas are certainly capable of producing distant metastasis in the absence of an obvious primary source. 

Dehner LP. Peripheral and central primitive neuroectodermal tumors A nosologic concept seeking a consensus. Arch Pathol Lab Med. E986 EE0 997-E005. 

Dehner LP. Primitive neuroectodermal tumor and Ewing s sarcoma. Am J Surg Pathol. E993 E7 E-E3. 

Jacinto CM, Grant-Kels JM, Knibbs DR, et al. Malignant primitive neuroectodermal tumor presenting as a scalp nodule. Am J Dermatopathol. 1991 13 63-70. 

Banerjee SS, Agbamu DA, Eyden BP, et al. Clinicopathological characteristics of peripheral primitive neuroectodermal tumor of skin and subcutaneous tissue. Histopathology. 1997 31 355-366. 

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