World Health Organization<\/span> (WHO), granular cell tumor is a benign tumor of soft tissue and is thought to be of Schwann cell origin. It is composed of a poorly demarcated accumulation of plump granular cells, which are often intimately associated with skeletal muscle.<\/em><\/p>\nGranular cell tumors\u00a0are distinctive neoplasms with granular eosinophilic<\/span> cells containing abundant lysosome-rich cytoplasm<\/span>. Previously utilized names include \u201cgranular cell myoblastoma,\u201d \u201cgranular cell neurofibroma,\u201d and \u201cgranular cell schwannoma,\u201d a reflection of various histogenetic hypotheses. They occur in both benign and malignant form, although the latter is very rare. As a tumor group, they share many morphologic, immunohistochemical, and ultrastructural features. The current concept is that\u00a0granular cell tumors\u00a0are nerve sheath<\/span> derived, in keeping with their close association with small to midsize nerves, including rare spinal or cranial examples.<\/p>\nA benign lesion has excellent outcomes after surgical resection however, a malignant GrCT is aggressive and has a poor prognosis. Differentiating a malignant tumour from a benign tumour is very important, as malignant GrCTs have a mortality rate of 40%. A malignant lesion is confirmed via histopathological examination<\/span>.<\/p>\nFanburg-Smith criteria is used for grading malignancy in GrCT. GrCT is an asymptomatic, slow-growing solitary mass that occur at a wide variety of sites. On ultrastructural examination, it appears to be granular, showing acidophilic cytoplasm<\/span> that contains abundant lysosomes. A true GCT shows strong S-100 protein<\/span> expression<\/span> immunohistochemically, and many show prominent basal lamina and intracytoplasmic filaments ultrastructurally. A malignant granular cell tumor differs from benign counterpart by few clinical features – Longer clinical duration with sudden rapid growth, Larger size on presentation as compared to benign tumors (4-5.0 cm and <3 cm respectively). Often involves a history of local recurrence, Frequent localization to the lower limbs unlike benign granular cell tumors, which commonly occur in the head, neck, and tongue.<\/p>\nFanburg-Smith\u00a0proposed 6 histologic<\/span> criteria for the diagnosis of atypical and MGCTs. It included necrosis<\/span>, spindling, vesicular nuclei with large nucleoli, increased mitotic activity (>2 mitoses\/10 high-power fields at \u00d7200 magnification), high nuclear-to-cytoplasmic ratio, and pleomorphism<\/span>. Neoplasm’s that one or two criteria were classified as atypical, that met three or more were classified as histologically malignant, and that displayed only focal pleomorphism but fulfilled none of the other criteria were classified as benign. In 2004, Wang\u00a0et<\/em>\u00a0al<\/em> proposed a modification of mitotic count (>5\/50 HPF instead of >2\/10 HPF). Immunohistochemistry of tumor cells is positive for S-100, Ki-67, and p53<\/span> and negative for ER, PR, Her2neu, GCDFP and PanCK.<\/p>\nThe origin of granular cell tumors is uncertain and it was thought earlier that they arise from skeletal muscle, fibroblastic, histiocytic, or undifferentiated mesenchymal cell origin. Recent evidence shows that monoclonal antibody<\/span> KP-1, reacts positively with schwannomas and granular cell tumors, which proves that these tumors arise from Schwann’s cells. Also, granular cell tumors cytoplasmically staining for S-100 protein are closely associated with nerves and are often present in distal nerve trunks. All these features support a Schwann’s cell origin for GCTs.<\/p>\nAlmost 30-40% of cases occur in the skin or\u00a0subcutaneous\u00a0tissue whereas approximately 50% on the head and neck with nearly 25% on the tongue. However, they may occur at any skin or\u00a0mucosal\u00a0site and occasionally affect internal organs.<\/p>\n
Granular cell tumor (GCT) is an uncommon benign tumor founded in any part of the body but mainly in the tongue. Though it can develop at any age, it is commonly found between the second and sixth decades of life. Histologically, diagnosis is easy but can be misdiagnosed if not well observed. Misdiagnosis may occur because the lesion often shows pseudoepitheliomatous hyperplasia<\/span>, and islands of epithelium can be seen in the connective tissue. This characteristic leads to a wrong interpretation as squamous cell carcinoma (SCC) mainly when the tumor is located in an area where it is more likely to occur. Besides the pseudoepitheliomatous hyperplasia, this tumor is also composed of polygonal cells with eosinophilic granular cytoplasm and small nuclei. Invasion is commonly seen, however, there is no atypia.<\/p>\nWithin the GI tract<\/span>,\u00a0granular cell tumors\u00a0are most common in the esophagus<\/span> followed by the colon, perianal<\/span> region, stomach, appendix, and small bowel<\/span>. Granular cell tumors\u00a0of the GI tract typically present as mucosal or submucosal masses and present an immunophenotype identical to\u00a0granular cell tumors\u00a0of other sites. S-100 protein, CD57, and vimentin are usually strongly and diffusely reactive.<\/p>\nAn apparently inconsistent set of histologic features have been described on few patients with malignant GCTs. Gamboa explained this heterogeneity and stated that there were two histologic types of malignant GCTs. The first type is with classical cytologic<\/span> and histologic features of malignancy<\/span>. The second one with deceptively bland cytologic and histologic findings. Electron microscopy and immunohistochemistry are routinely used for the confirmation of the diagnosis of GCT.<\/p>\nMore than 98% of granular cell tumours are\u00a0benign\u00a0and gets cured following complete\u00a0excision<\/span>.\u00a0Malignant\u00a0change has been reported very rarely and tends to be more reliably predicted by aggressive clinical features (rapid growth, size greater than 4cm,\u00a0necrosis, lymph node<\/span> involvement) rather than\u00a0histological\u00a0features. Therefore, large or aggressively growing tumours are followed up postoperatively. Most often surgical\u00a0excision\u00a0of the\u00a0tumour\u00a0provides a diagnosis and the treatment of choice.<\/p>\nPeripheral nerves\u00a0are complex tissues composed of a variety of cellular elements, specifically\u00a0Schwann cells, perineurial cells, and neuronal processes (axons), enveloped by\u00a0connective tissue\u00a0elements. Neoplasms originating from peripheral nerve often recapitulate the\u00a0phenotype<\/span>\u00a0of underlying cell elements and range from benign, locally aggressive neoplasms with potential for\u00a0malignant degeneration, to overtly malignant, highly aggressive neoplasms. The proper diagnosis not only has\u00a0therapeutic\u00a0implications but is also increasingly relevant to\u00a0genetic counseling.\u00a0Due to their association with multisystemic\u00a0genetic syndromes<\/span>, including\u00a0neurofibromatosis types 1 and 2,\u00a0schwannomatosis,\u00a0Carney Complex, and\u00a0multiple endocrine<\/span> neoplasia\u00a0type IIB. Malignant peripheral nerve sheath tumors have recently been found to have frequent\u00a0mutations\u00a0in components of the\u00a0polycomb repressive complex 2\u00a0(SUZ12, EED), resulting in consistent\u00a0epigenetic alterations, particularly loss of\u00a0histone\u00a0H3K27 trimethylation. All these findings have translated into diagnostic\u00a0biomarkers\u00a0useful in surgical pathology<\/span> diagnosis, including immunohistochemical antibodies recognizing the loss of\u00a0neurofibromin\u00a0and H3K27 trimethylation. In summary, peripheral nerve sheath tumors represent a heterogeneous group, with important diagnostic challenges that are important to recognize.<\/p>\nThe histogenesis of the Granular cell tumor is still a subject of controversy. GCT will continue to interest clinicians and pathologists alike because of their myriad sites of occurrence and their mimicry of other lesions both benign and malignant.<\/p>\n
References<\/p>\n
\n- Torrijos-Aguilar A, Alegre-de Miguel V, Pitarch-Bort G, Mercader-Garc\u00eda P, Fortea-Baixauli JM. Cutaneous granular cell tumor: a clinical and pathologic analysis of 34 cases. Actas Dermosifiliogr. 2009;100:126\u201332. Spanish.<\/li>\n
- Elkousy H, Harrelson J, Dodd L, Martinez S, Scully S. Granular cell tumors of the extremities. Clin Orthop Relat Res. 2000;(380):191\u20138.<\/li>\n
- Rekhi B, Jambhekar NA. Morphologic spectrum, immunohistochemical analysis, and clinical features of a series of granular cell tumors of soft tissues: a study from a tertiary referral center. Ann Diagn Pathol. 2010;14:162\u20137<\/li>\n
- 4.Thacker MM, Humble SD, Mounasamy V, Temple HT, Scully SP. Case report. Granular cell tumors of extremities: comparison of benign and malignant variants. Clin Orthop Relat Res. 2006;455:267\u201373.<\/li>\n
- Arai E, Nishida Y, Tsukushi S, Sugiura H, Ishiguro N. Intramuscular granular cell tumor in the lower extremities. Clin Orthop Relat Res. 2010;468:1384\u20139.<\/li>\n
- Fanburg-Smith JC, Meis-Kindblom JM, Fante R, Kindblom LG. Malignant granular cell tumor of soft tissue: Diagnostic criteria and clinicopathologic correlation. Am J Surg Pathol 1998;22:779-94.<\/li>\n
- Rejas RA, Campos MS, Cortes AR, Pinto DD, de Sousa SC. The neural histogenetic origin of the oral granular cell tumor: an immunohistochemical evidence. Med Oral Patol Oral Cir Bucal. 2011;16:e6\u201310.<\/li>\n
- Dive A, Dhobley A, Fande PZ, Dixit S. Granular cell tumor of the tongue: Report of a case. J Oral Maxillofac Pathol. 2013;17:148.<\/li>\n<\/ol>\n
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<\/p>\n","protected":false},"excerpt":{"rendered":"
Table of Contents I. Introduction II. History and Origin III. Diagnosis of Granular Cell Tumor IV. Histological Criteria for Diagnosis of Atypical and Malignant Granular Cell Tumors V. Origin and Occurrence of Granular Cell Tumor VI. Treatment and Prognosis VII. Conclusion Granular cell tumor (GrCTs), first described by Abrikissof\u2018 in 1926, named it \u201cmyoblastenmyome,\u201d […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"off","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[31],"tags":[75],"class_list":["post-2926","post","type-post","status-publish","format-standard","hentry","category-news","tag-granular-cell-tumor"],"_links":{"self":[{"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/posts\/2926","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/comments?post=2926"}],"version-history":[{"count":2,"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/posts\/2926\/revisions"}],"predecessor-version":[{"id":9285,"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/posts\/2926\/revisions\/9285"}],"wp:attachment":[{"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/media?parent=2926"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/categories?post=2926"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.mybiosource.com\/learn\/wp-json\/wp\/v2\/tags?post=2926"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}