Multiple granular cell tumors of the oral cavity: report of a case and review of the literature

Molecular Characterization of Multifocal Granular Cell Tumors

Granular cell tumors (GrCT) were recently found to be driven by inactivating mutations in vacuolar H + -ATPase (V-ATPase) genes, most frequently ATP6AP1 and ATP6AP2 . Multifocal presentation is present in ~10% of cases; however, the relationship between multifocal tumors in a given patient has not been elucidated. We hypothesized that benign-appearing multifocal GrCT are molecularly distinct whereas paired primary and metastatic malignant GrCT share identical mutations. To test this, we conducted targeted next-generation sequencing of the V-ATPase genes in multifocal GrCT and whole exome and Sanger sequencing in paired primary and metastatic malignant GrCT. Thirteen patients with≥2 GrCT were identified (total of 43 tumors). Forty-two tumors were successfully sequenced. Tumors showed somatic mutations in 3 of the 10 targeted genes in 32 of 42 samples (76%). Twenty tumors showed mutations in ATP6AP1 (48%), 10 tumors had mutations in ATP6AP2 (24%), and 2 tumors showed mutations in ATP6V0A4 (5%). Predicted loss-of-function mutations were found in ATP6AP1 in 17 tumors (40%), in ATP6AP2 in 10 tumors (24%), and in ATP6V0A4 in 1 tumor (2%). In 8 patients, mutually exclusive mutations were detected in at least 2 tumors per patient. Two patients were identified with malignant GrCT with material available from both primary and metastatic sites. Identical frameshift insertions were found in ATP6AP1 in 1 case and the second case showed identical nonsense mutations in ATP6AP1 . In conclusion, multifocal GrCT within an individual patient are molecularly distinct, while paired primary and metastatic GrCT share identical mutations.

Oral granular cell tumour: A multicentric study of 56 cases and a systematic review

OBJECTIVE

Granular cell tumour (GCT) is a benign neoplasm that originates from Schwann cells. Within the oral cavity, it usually appears as a lingual nodule and especially amongst female adults. Histologically, GCT shows a proliferation of polygonal cells with eosinophilic granular cytoplasm, which can be associated with a pseudoepitheliomatous hyperplasia (PEH). In this study, we analyse the main clinicopathological data of intraoral GCT and we compare our results with previous studies.

MATERIAL AND METHODS

We have studied a series of 56 cases of oral GCT in Spain and Brazil, and we have conducted a systematic review in PubMed, Web of Knowledge and Scopus databases, using the keywords: "granular cell tumour" and oral.

RESULTS

In our series, GCT appeared as an asymptomatic benign tumour that is more frequent in women and in the tongue. PEH was observed in 32% of the lesions. In the review, we collected 282 cases of oral GCT with a similar clinical profile; seven patients had multiple lesions, and 33% of the cases presented PEH. No cases of malignant oral GCT have been described to date. GCT is an uncommon oral benign neoplasm, mainly unique and asymptomatic, derived from Schwann cells.

CONCLUSIONS

Although the etiopathogenesis of this oral tumour is unknown, its characteristics suggest that it could have a reactive nature. Conducting a complete clinicopathological study in all intraoral GCT is fundamental in order to dismiss other entities, including oral carcinoma.

Oral Granular Cell Tumor: Report of Case Series and a Brief Review of the Literature

Background/Aim: The present analysis focuses on examining a case series of eight patients diagnosed with a granular cell tumor located in the oral cavity. Case series: The patients’ clinical states were thoroughly studied, along with the histopathological and immunohistochemical examinations findings. Their surgical treatment and postoperative course are also within the scope of this analysis. Numerous histogenesis theories and the appropriate tumor treatment are mentioned within the article being always in accordance with the relative literature. Conclusions: Oral granular cell tumor is a benign oral disease of possible neural origin commonly located on the tongue. Surgical excision is the treatment of choice. In any case, histological and immunohistochemical examination confirm both the clinical diagnosis and the differential diagnosis between oral squamous cell carcinoma.

Bilateral multifocal upper extremity atypical granular cell tumors presenting as long-standing right wrist and left hand masses in a 15-year-old African-American female

Granular cell tumor (GrCT) is a benign nerve sheath tumor. Atypical and malignant variants of GrCT are rare but have been well described. We report a case of multifocal symmetric atypical GrCT in the bilateral hand/wrists of a 15-year-old African-American female. The initial clinical impression for both masses was favored to be ganglion cysts. Ultrasound findings of both masses revealed hypoechoic soft tissue lesions with some internal echogenicity favoring complex cysts. On excision, both masses were histologically circumscribed, lobulated and attached to tendon. Large epithelioid cells with abundant granular eosinophilic cytoplasm arranged in syncytial cords and trabeculae percolated through collagen. Many cells had pleomorphism and/or prominent nucleoli. Mitotic figures, spindling, high nuclear-to-cytoplasmic ratio and necrosis were absent. Both masses showed diffuse S100 protein but negative desmin and pancytokeratin expression. Ki-67 index was 1% to 2%. p53 was positive in 5% to 10% of nuclei. Both masses met criteria for atypical (but not malignant) GrCT. Our case shows that atypical GrCT may be not only multifocal but also symmetric. We speculate that migration of defective neural crest stem cells along both upper limb buds during embryogenesis may have allowed these essentially identical tumors to arise in similar locations bilaterally simultaneously.

Granular cell tumor mimicking a squamous cell carcinoma of the tongue: a case report

BACKGROUND

Granular cell tumor is a rare benign tumor that can present a pseudoepitheliomatous hyperplasia of the covering epithelium. This lesion is not encapsulated and can be characterized by a pseudo invasive growth pattern, represented by the tumoral cells that infiltrate between adjacent connective tissue elements. Diagnostic difficulties may arise because histopathological features of the pronounced pseudoepitheliomatous hyperplasia can be confused with a well-differentiated oral squamous cell carcinoma. The aim of this case report is to demonstrate the role of an immunohistochemical panel in the diagnosis of a granular cell tumor in the tongue with clinical and microscopic features resembling an oral squamous cell carcinoma.

CASE PRESENTATION

A 44-year-old white man with a history of heavy smoking and alcohol abuse presented an ulcerated nodular lesion in the dorsum of the tongue. The lesion was asymptomatic with fast growth. The clinical diagnosis was an oral squamous cell carcinoma. An incisional biopsy was performed and the ensuing histopathological analysis showed a pseudoepitheliomatous hyperplasia in the overlying epithelium mimicking the invasion of epithelial tumor cells into the connective tissue as in an oral squamous cell carcinoma. Immunohistochemical antibodies (S-100, vimentin, CD68, p53, Ki-67, E-cadherin, collagen IV and cytokeratin AE1/AE3) were used to characterize molecular aspects of the lesion. Strong staining of S-100 protein, CD68, vimentin, E-cadherin and low proliferative activity observed with Ki-67 expression confirmed the diagnosis of a granular cell tumor. The patient was submitted to surgical excision of the whole lesion. At a 12-month check-up, there was no evidence of recurrence.

CONCLUSION

This case report showed that the immunohistochemical profile was helpful in determining the clinical behavior of the tumor and establishing the final diagnosis with appropriate treatment.

Multiple granular cell tumors with metachronous occurrence in tongue and vulva. Clinicopathological and immunohistochemical study

Granular cell tumor (GCT) usually occurs as a single tumor, although sometimes multiple lesions can occur. In present report we analyze the clinicopathological and immunohistochemical features of a multiple GCT involving the tongue of a 14-year-old girl, with no other abnormalities, with a metachronous occurrence of a second GCT in vulva, after a period of 10 years. Both tumors revealed S-100, vimentin and CD57 positivity. In addition, over expression of calretinin was observed in tumor cells located in the vicinity of pseudoepitheliomatous hyperplasia (PEH) of the tongue. Tumor vasculature situated close to the PEH showed marked CD105 reactivity, data not described so far, suggesting an interaction between PEH cells and underlying stroma, since GCT completely lacks CD105 vessels. Our study emphasizes that patients with GCT, especially young patients, should be followed long-term, looking for multiple tumors or other abnormalities suggestive of a systemic syndrome, given the associations described in multiple GCT.

Granular cell tumor presenting as a tongue nodule: two case reports

Introduction

Granular cell tumor is an uncommon neoplasm that can occur in any part of the body, including the orofacial region. The tumor is usually benign, but there are reports of cases in which the tumor shows a locally aggressive behavior, malignancy, and distant metastases. The most widely accepted hypothesis is that granular cell tumor arises from the altered metabolism of Schwann cells. The tumor is typically asymptomatic and appears as a nodule that does not exceed 3 cm.

Case presentation

In case 1, a 26-year-old Caucasian man was seen at the Oral Medicine out-patient clinic of the São José dos Campos Dental School, Universidade Estadual Paulista, with a 'small blister on the tongue', which he had noted approximately three years ago. The nodule was located on the dorsum of the tongue, measured about 1.5 cm in diameter, and was not tender to palpation. Treatment consisted of an excisional biopsy performed on the basis of the diagnostic hypothesis of granular cell tumor, which was confirmed by microscopic analysis. In case 2, a 31-year-old Caucasian woman attended the out-patient clinic of the São José dos Campos Dental School, Universidade Estadual Paulista, with a five-year history of a 'painful lump on the tongue'. Intra-oral examination revealed the presence of a nodular lesion measuring approximately 0.8 cm in diameter, which was located deep in the submucosa of the right lateral margin of the tongue. Treatment consisted of an excisional biopsy performed on the basis of the differential diagnosis of neurofibroma and granular cell tumor. Microscopic analysis defined the final diagnosis of granular cell tumor.

Conclusions

Granular cell tumor is an uncommon tumor that must be carefully diagnosed and treated correctly.

Granular cell tumour of tongue: A case report

Granular cell tumour, also known as Abrikossoff tumour, is a relatively uncommon benign neoplasm, which is more commonly found in females in the 4th to 6th decades of life even though it can occur in all ages. It occurs in all areas of the body but about 45-65% of all lesions are reported in the head and neck region. Intraoral lesions represent about 70% of the granular cell tumours of the head and neck, and account for 1/3 of all cases affecting the whole body. Most of the intraoral lesions occur on the tongue, usually on the lateral aspect, followed by the buccal mucosa and hard palate. Although majority of granular cell tumours are benign, some are clinically aggressive and a few frankly malignant forms have been reported. Some benign lesions exhibit surface ulcerations and this clinical appearance, combined with the overlying pseudoepitheliomatous hyperplasia, seen histologically, may lead to misdiagnosis of malignancy if adequate biopsy material was not taken. A case of granular cell tumour which occurred on the midline area of the dorsum of the posterior 1/3 of the tongue is reported in a 20-year-old female patient. It is interesting because the patient was younger than the average age of occurrence and the tumour occurred in a similar site to that of a lingual thyroid.

The unique simultaneous occurrence of a squamous cell carcinoma and a granular cell tumor of the tongue at the same site: a histological and immunohistochemical study

We report a case of a 47-year-old man with a granular cell tumor (GCT) of the tongue colocalized with a squamous cell carcinoma. To our knowledge, this is the first case to be reported in the literature with such an association. Furthermore, we performed an immunohistochemical analysis with p63 to distinguish pseudoepitheliomatous hyperplasia from invasive squamous cell carcinoma. Clinicians and pathologists must be made aware of this potential diagnostic pitfall so that the workup of a tongue lesion does not end prematurely with a benign diagnosis of granular cell tumor with overlying pseudoepitheliomatous hyperplasia.

Morphometrical differences between pseudo-epitheliomatous hyperplasia in granular cell tumours and squamous cell carcinomas

AIM

Granular cell tumour (GCT) is a benign tumour which occasionally induces pseudo-epitheliomatous hyperplasia (PEH) of the covering epithelium, mimicking squamous cell carcinoma (SCC) invasion. PEH cells do not show marked atypia, but the presence of pseudoinvasive patterns remains a diagnostic problem since several misdiagnosed cases have been reported. This study investigated objective morphometric criteria to distinguish GCT-PEH from SCC.

METHODS AND RESULTS

The complexity of the epithelial connective tissue interface (ECTI) in 57 profiles from nine SCC and 12 GCT-PEH cases was analysed using fractal geometry. Epithelial and non-epithelial cells were segmented using a space partition procedure and analysed morphometrically. GCT ECTI profiles were significantly more complex than those of SCC. The complexity of ECTI quantified by global and local fractal dimensions allowed up to 86% correct discrimination between GCT-PEH and SCC. The cell-wise discrimination between the two entities using cellular morphology was 76% but when the two approaches were combined, the correct discrimination was 96%.

CONCLUSIONS

The architectural features of GCT-PEH and SCC show differences which, when quantified, could be used to differentiate the two diagnostic classes. Characterization of these differences may help to elucidate some of the mechanisms of tumour infiltration and metastasis.

Immunohistochemical evaluation of cell proliferation antigen Ki-67 and apoptosis-related proteins Bcl-2 and caspase-3 in oral granular cell tumor

PURPOSE

We sought to evaluate the cell proliferation activity and immunohistochemical expression of proteins that promote or inhibit apoptosis in oral granular cell tumor (GCT).

STUDY DESIGN

Immunohistochemistry for Ki-67, a cell proliferation marker; Bcl-2, an anti-apoptotic protein; and caspase-3, a protein implicated in the execution of apoptosis, was performed on tissues from 12 patients with GCT of the tongue.

RESULTS

Nuclear immunostaining for Ki-67 was observed only in isolated GCs (less than 2%). All patients exhibited cytoplasmic immunoreactivity for Bcl-2 in the majority of tumor cells. Cytoplasmic staining for caspase-3 was also present in more than 50% of GCs in all tumors.

CONCLUSIONS

GCT cells display low proliferation activity, a finding possibly related to their benign behavior. Caspase-3 expression suggests activation of the apoptotic cascade in the GCs, but persistence of the cells in the tissues could be attributed to the expression of Bcl-2 protein, a molecule that functions as a survival factor.

Granular cell tumor of the lacrimal sac and nasolacrimal duct: no invasive behavior with incomplete resection

OBJECTIVE

Granular cell tumors are rare tumors of the periorbital region, and we present the second such case in the lacrimal sac. The natural history and clinical behavior of these tumors is reviewed.

DESIGN

Case report.

METHODS

The clinical presentation, workup, surgical approach, and pathology of a case of granular cell tumor of the lacrimal sac are presented.

RESULTS

There has been no recurrence of the lacrimal sac tumor with incomplete resection.

CONCLUSIONS

This case history further adds to the understanding of the biologic behavior of granular cell tumors in the periorbital region.

Epibulbar granular cell tumor. Report of a case and review of the literature

BACKGROUND

The granular cell tumor (GCT) is a common, usually benign, neoplasm of uncertain histogenesis that may affect any organ in the body. It occurs rarely in ophthalmic sites, where orbital location is most frequent. The purpose of this report is to describe a unique case of an epibulbar, subconjunctival GCT in a child.

METHOD

Histopathologic examination of the excised tumor included standard and immunohistochemical staining of formaldehyde-fixed, paraffin-embedded tissue.

RESULTS

Histopathologic study showed the characteristic morphology of GCT. Immunohistochemistry was strongly positive for vimentin, weakly and partly positive for neuron-specific enolase, and negative for S-100 and HAM-56.

CONCLUSIONS

Granular cell tumor must be added to the differential diagnosis of epibulbar masses. Immunohistochemistry of the tumor in this case suggests an uncommitted mesenchymal cell origin.