Granular cell leiomyosarcoma of the skin

Leiomyosarcoma of the skin: review of the literature with an emphasis on prognosis and management

Leiomyosarcoma (LMS) of the skin is rare, and no management guideline currently exists. Although LMS is historically classified as either dermal (cutaneous) or subcutaneous, definition for its classfication is inconsistent in the literature. Studies on the managenent of LMS are scarce, and there is no consensus on the appropriate surgical margin for the treatment of LMS. While a 1 cm margin may be sufficient in cutaneous LMS, wider margins may be required for subcutaneous tumors. Mohs micrographic surgery is a promising surgical modality for the treatment of cutaneous LMS. In this review, current knowledge on LMS is summarized and a practical approach to the management of this rare neoplasm is proposed.

Leiomyosarcoma and Pleomorphic Dermal Sarcoma: Guidelines for Diagnosis and Treatment

There are 3 types of leiomyosarcoma of the skin: dermal, subcutaneous, and metastatic cutaneous. Dermal leiomyosarcoma arises from smooth muscle fibers in arrector pili muscles, genital dartos muscles, and the nipple-areola complex. It is an intermediate-grade tumor associated with a tendency for local recurrence (24%) and low metastatic potential (4%). Subcutaneous leiomyosarcoma originates from smooth muscle in blood vessel walls and has higher rates of local recurrence (37%) and metastasis (43%). Plemorphic dermal sarcoma typically affects elderly patients and arises in sun-exposed areas (e.g., the scalp). Its histologic and immunohistochemical characteristics are similar to those of atypical fibroxanthoma, but it is more aggressive (metastasis rate of 10-20%). Histologically, it can be distinguished from atypical fibroxanthoma by the observation of subcutaneous tissue invasion, perineural invasion, and foci of necrosis.

Primary leiomyosarcoma of the skin: a comprehensive review on diagnosis and treatment

Sarcomas are a heterogeneous group of mesenchymal tumors which can affect bone and soft tissue. Leiomyosarcoma (LMS) is a rare subtype localized to the skin or subcutaneous tissue. Due to the heterogeneity of sarcomas, reviews and guidelines with an in-depth focus specifically on primary LMS of the skin are sparse. This article is intended to provide an up to date and systematic overview on diagnosis, treatment, and surveillance of this rare entity to provide a framework for decision making and management for dermato-oncologists. We discuss novel treatment options for advanced disease such as targeted therapy with kinase inhibitors and immune checkpoint blockade which may improve the prognosis even in advanced stages of LMS.

Cutaneous Smooth Muscle Tumors: A Review

Smooth muscle tumors occur infrequently in the skin. They consist of a diverse group of lesions representing hamartomas as well as benign and malignant neoplasms. They may arise from arrector pili muscle, specialized smooth muscle of the genitalia, or vascular smooth muscle. Although rare, accurate diagnosis and classification of cutaneous smooth muscle proliferations is important as they can exhibit a range of clinical behavior and may be associated with underlying syndromes. This review summarizes the clinicopathologic spectrum of smooth muscle tumors involving the skin.

Benign Granular Cell Tumor of the Breast: A Misleading Disease

Granular cell tumor (GCT) is a relatively rare neoplasm, and almost always benign in its prognostic behavior. Location of this tumor in the breast presents serious problems for differential diagnosis, both from a clinical point of view and at gross pathological examination, because of its resemblance to carcinoma. Fine needle aspiration biopsy and intraoperative frozen section examination may not be of any further help. The histogenesis of these lesions has been widely debated in the past, but no universally accepted conclusion has been reached. Most GCTs appear to be derived from Schwann cells, but many different neoplastic and non-neoplastic lesions show granular cell changes. Therefore, GCT should not be considered as a single entity but as the result of a cytoplasmic change due to still unknown metabolic alterations that may occur in various cell types. No firm conclusions can be drawn regarding the suspected hormonal influence on the development of breast GCT.

The authors describe three typical cases of breast GCT that occurred in patients of different ages, and discuss the most important questions concerning this lesion.

Granular Cell Basal Cell Carcinoma of the Skin. Report of a Case with Immunocytochemical Positivity for Lysozyme

Granular cell tumors have been described in many sites throughout the body. To our knowledge, few cases have been described in the literature. We report here the sixth case, in which positivity for lysozyme was also observed for the first time. The problems of the histogenesis and differential diagnosis of this rare variant of basal cell carcinoma are also discussed.

Leiomyosarcoma of the great saphenous vein (vena saphena magna) with granular cell change: Report of a superficial neoplasm

The great saphenous vein (GSV) corresponds to the main superficial large-caliber vessel affected by leiomyosarcoma (LMS). Given its superficial location and because signs of vascular origin may not be clinically apparent, LMS of the GSV may be misinterpreted clinically as superficial nonvascular soft tissue mass. Herein, we report a case on the distal portion of the right GSV of a 57-year-old man. The histopathological recognition of a large-caliber vein-associated LMS (with granular cell change) in an incisional biopsy specimen was crucial to guide radiological evaluation and confirmation of a superficial vascular LMS before surgical treatment. Recognizing this entity in small biopsies is important as its surgical treatment and prognosis differ substantially from nonvascular superficial (ie, subcutaneous and dermal) LMSs. In addition, because vascular LMSs can involve long vessel segments, underestimation of extent of disease is a risk. To the best of our knowledge, granular cell change has not been documented in LMS of the GSV.

Granular cell differentiation: A review of the published work

Since the initial description of the granular cell tumor in 1926, numerous other neoplasms, both benign and malignant, have been described to exhibit granular cell change. In most cases, diagnosis remains straightforward via recognition of retained histopathological morphology of the archetypal tumor, despite the presence of focal granular appearance. However, tumors with granular cell differentiation can present a diagnostic challenge either by mimicking alternative diagnoses, or by failing to exhibit architectural clues of the primary entity, thus requiring an immunohistochemical work-up. In light of this, it is important to be aware of the various entities that have been reported to exhibit granular cell morphology. In this review such tumors are discussed along with pertinent clinical and histopathological features.

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.

Gastric Epithelioid Stromal Tumor (Leiomyoma) With Granular Changes

A unique case of gastric epithelioid stromal tumor (leiomyoma) demonstrating granular changes is reported. Microscopically, the tumor was composed of polygonal or fusiform cells with a coarse, granular eosinophilic cytoplasm, focally admixed with fascicles of spindle-shaped cells. A marked lymphoid infiltrate forming follicles was also a characteristic finding. Immunohistochemically, these cells were positive for alpha-smooth-muscle actin, HHF-35 (muscle-specific actin), and NKI/C3 but negative for desmin, S100 protein, vimentin, lysozyme, and Mac-387. This case demonstrates that granular cell changes and prominent lymphoid aggregates are not limited to gastric stromal tumors with neural differentiation.

Fibrous papule of the face with granular cells

Fibrous papule of the face is a common benign lesion located most often on the nose. It presents usually as a single small, firm, skin-coloured papule and is often misdiagnosed as melanocytic naevus, wart or small nodular basal cell carcinoma. Histopathologically, the lesions are characterized by involvement of the upper dermis by a fibrovascular proliferation and scattered triangular or stellate, often multinucleated cells. Uncommon histopathologic variants of fibrous papule of the face include hypercellular, clear-cell, pleomorphic, pigmented, inflammatory and granular-cell types. We present here a patient with the syndrome of familial cancer and fibrous papule of the face with granular cells. The granules stained strongly with PAS stain, as well as with CD68 and NKI/C3 immunostains, whereas S-100 protein resulted negative. In our patient the mutations in the 2 most often affected DNA mismatch repair genes of Muir-Torre syndrome were not found, therefore the origin of the familial cancer syndrome remains unknown. Probably the occurrence of the granular-cell fibrous papule of the face was coincidental.

Leiomyosarcoma of the skin with osteoclast-like giant cells: a case report

Introduction

Osteoclast-like giant cells have been noted in various malignant tumors, such as, carcinomas of pancreas and liver and leiomyosarcomas of non-cutaneous locations, such as, uterus and rectum. We were unable to find any reported case of a leiomyosarcoma of the skin where osteoclast-like giant cells were present in the tumor.

Case presentation

We report a case of a 59-year-old woman with a cutaneous leiomyosarcoma associated with osteoclast-like giant cells arising from the subcutaneous artery of the leg. The nature of the giant cells is discussed in light of the findings from the immunostaining as well as survey of the literature.

Conclusion

A rare case of cutaneous leiomyosarcoma with osteoclast-like giant cells is reported. The giant cells in the tumor appear to be reactive histiocytic cells.

Malignant granular cell tumor with unusual histological features

Malignant granular cell tumor, although uncommon, should be differentiated from a number of granular cell-containing tumors. Reported herein is a distinctive variant of malignant granular cell tumor, clinically presenting as a rapidly enlarging scrotal mass, in which some areas morphologically displayed features indistinguishable from Kaposi sarcoma. Cells in areas simulating Kaposi sarcoma were immunohistochemically the same as typical granular cells in other portions of the tumor. The recognition of this pattern is important because it may predominate and overshadow the original nature of tumor.

Cutaneous oncocytoma ? a report of three cases and review of the literature

The oncocyte is a cell characterized by capacious, eosinophilic, finely granular cytoplasm, and lesions composed primarily of oncocytes are termed oncocytomas. Whereas oncocytic metaplasia has been reported in various cutaneous neoplasms, oncocytomas typically occur in the kidneys, thyroid and salivary glands and are uncommon in the dermatopathology literature. We present three cases of cutaneous oncocytoma so that dermatopathologists are cognizant of this uncommon entity. Although some believe that oncocytomas are locally aggressive lesions, our cases indicate that their clinical course is perhaps as banal as their histology.

HMB-45 and Melan-A are Useful in the Differential Diagnosis Between Granular Cell Tumor and Malignant Melanoma

Granular cell tumors (GCTs), especially if atypical or malignant, may share cytomorphologic and architectural features with malignant melanoma, when the latter shows granular cell change. In many cases, these neoplasms can be differentiated from each other on histologic grounds, but distinction may sometimes be challenging. By immunohistochemistry, both tumors are strongly positive for S-100 protein and frequently express other nonspecific markers such as CD68, NSE, and NKIC3. In the current study, we reviewed 60 cases of conventional cutaneous, mucosal, and visceral GCT and studied the use of immunoperoxidase staining for the differential diagnosis between malignant melanoma and GCT. Immunohistochemical stains for S-100 protein, A, HMB-45, and microphthalmia transcription factor (MITF) were performed in all cases. All of the tumors were positive for S-100 protein. MITF immunostaining was diffusely positive in 53 (88%) cases, focally positive in three (5%) cases, and negative in four (7%). Fifty-seven (95%) tumors were negative for Melan-A, one case was focally positive, and two cases showed rare positive tumor cells. None of the tumors expressed HMB-45. In conclusion, GCT and malignant melanoma can be reliably differentiated on the basis of immunohistochemical stains in the majority of cases. Although not always positive in malignant melanoma, in this context, HMB-45 expression seems to be 100% specific for the diagnosis of melanoma. Melan-A is slightly less specific, with rare cases of GCT showing focal positivity. MITF is not useful in this differential-93% of the GCTs in our series showed nuclear reactivity for this marker. The latter finding highlights the limited specificity of this antibody in the diagnosis of melanocytic tumors.

Dermal non-neural granular cell tumour (so-called primitive polypoid granular cell tumour): a distinctive entity further delineated in a clinicopathological study of 11 cases

AIMS

Cutaneous and soft tissue granular cell tumour is a well-characterized benign neoplasm of neural origin. However, there remains a subcategory of granular cell tumour, first described by Le Boit as 'primitive polypoid granular cell tumour', that shows no obvious line of differentiation. The aim of this study is to further the characterization of this lesion by undertaking a clinicopathological review.

METHODS AND RESULTS

Eleven cases of dermal non-neural granular cell tumour were retrieved from one of the authors referral archives (E.C.) and both the histology and immunohistochemistry reviewed. Clinical data with follow-up were obtained from the referring pathologists. The lesions most commonly occurred in young to middle-aged adults (nine cases, median = 33 years, age range 6-56 years), with a slight female predominance. They presented as painless nodules, mainly on the extremities or face. Local excision was the treatment of choice and up to date follow-up reveals no sign of recurrence. Histologically, eight cases were polypoid, while three cases were endophytic. The tumours were composed of elongated spindle-shaped to polygonal or round cells with prominent granular cell change, and tumour nuclei showing mild focal atypia to rare moderate atypia. Mitotic activity ranged from one to nine mitoses per 10 high-power fields (median = 2, mean = 3.8). Immunohistochemical labelling of the tumour cells demonstrated expression for NKI-C3 (n = 11), focal, weak positivity for CD68 (n = 10) and FXIIIa (n = 2). There was negative staining for S100 protein, smooth muscle actin, Melan-A, CD34, desmin and cytokeratin.

CONCLUSIONS

This analysis of 11 cases contributes to the characterization of this recently described entity, which despite some atypical histological features and no obvious line of differentiation, behaves in a completely indolent fashion.

Granular cell atypical fibroxanthoma

We report on two patients with granular cell atypical fibroxanthoma. Both neoplasms were solitary, light-tan, dome-shaped papules on sun-exposed areas of the head in two elderly white men. Microscopically, these neoplasms showed a dermal proliferation of pleomorphic granular cells with irregular hyperchromatic nuclei, multinucleated cells, and scattered mitoses. Immunohistochemical stains were positive for CD68 and vimentin and negative for Melan-A or human melanoma black (HMB)-45, S-100 protein, pancytokeratin, and actin, consistent with atypical fibroxanthoma. The differential diagnosis of granular cells in neoplasms containing cytological pleomorphism is challenging in view of the many different neoplasms that may present with granular cytoplasm. These include the conventional granular cell tumor and its malignant form, leiomyoma, leiomyosarcoma, dermatofibroma, dermatofibrosarcoma protuberans, and angiosarcoma.

Oncocytic metaplasia occurring in melanoma

BACKGROUND

Oncocytosis is a cellular feature characterized by the presence of a finely granular eosinophilic cytoplasm due to the accumulation of mitochondria. While this histologic trait can be found in normal tissues, it is also seen pathologically as a degenerative phenomenon. We recently reviewed a spectrum of oncocytic melanocytic nevi that did not have clinical significance. We now describe similar changes in melanoma.

METHODS

We retrospectively reviewed 12 melanomas noted to have prominent granular eosinophilic cytoplasm and completed ultrastructural studies. We obtained patient histories and clinical follow-up information from the patients' physicians.

RESULTS

All cases were primary melanomas and showed prominent oncocytosis in the majority of the lesional melanoma cells. Oncocytosis was observed in both melanoma in situ and invasive melanoma with a wide range of Breslow thicknesses (range, 0.45-5.05 mm). It occurred in the presence and absence of ulceration, regression, vascular invasion, and brisk tumor infiltrating lymphocytes. Ultrastructural studies revealed melanocytes with numerous distorted mitochondria.

CONCLUSION

Melanoma is capable of presenting in a variety of histologic guises, including oncocytic change. While our observations are preliminary, this pathologic curiosity likely represents a degenerative phenomenon of little prognostic importance.

A Malar Granular Cell Tumor in a Djungarian Hamster

'Granular cell' tumor observed in the malar subcutis of a Djungarian hamster was examined to determine its cellular origin. Histologically, the tumor consisted of a solid growth of oval or spindle-shaped large cells with abundant cytoplasm filled with eosinophilic granules that were periodic acid-Schiff-positive and diastase-resistant. Immunohistochemically, the tumor cells were positive to anti-vimentin and anti-desmin antibodies and a few cells showed positivity to anti-actin antibody as well. They did not react to myoglobin, S-100 protein, and glial fibrillary acidic protein (GFAP). Electron microscopic studies revealed that the tumor cells had pinocytotic vesicles, dense plaque and microfilaments. The first granular cell variant of myogenic tumor reported here in Djungarian hamsters was differentiated from granular cell tumor of Schwann cell origin.

Oncocytic metaplasia occurring in a spectrum of melanocytic nevi

Oncocytosis is defined as a metaplastic change characterized by the presence of cells with finely granular eosinophilic cytoplasm caused by the accumulation of mitochondria. Although this histologic feature can be found in normal tissues, it can also be seen pathologically as a degenerative phenomenon, where an accumulation of mitochondria is thought to compensate for an uncoupling of oxidative metabolism secondary to cellular aging. Oncocytic metaplasia can be observed in a variety of cutaneous lesions but, to our knowledge, has not been described in melanocytic nevi. We retrospectively reviewed 87 melanocytic nevi from 83 patients that showed significant oncocytic change. We obtained patient clinical history through surveys completed by the patients' physicians. Ultrastructural studies were performed on 4 representative nevi to confirm the presence of increased mitochondria. We prospectively reviewed 100 randomly selected nevi looking for oncocytic changes. We subsequently did not find any correlation with patient demographics or medical histories. Histologic evaluation showed granular eosinophilic cytoplasm in 75% or greater of lesional cells in two thirds of cases. This phenomenon occurred in all types of melanocytic nevi. Ultrastructural studies revealed melanocytes with numerous mitochondria in close apposition to melanosomes. Focal oncocytic change was identified prospectively in 38 of 100 randomly selected melanocytic nevi. We conclude that oncocytosis in melanocytic nevi is a relatively common and underrecognized phenomenon.

COL1A1-PDGFB gene fusion demonstrates a common histogenetic origin for dermatofibrosarcoma protuberans and its granular cell variant

Granular cell variant of dermatofibrosarcoma protuberans is very rare with only one report of two cases. We report a new case in which we demonstrated the presence of the dermatofibrosarcoma protuberans-specific COL1A1-PDGFB fusion from paraffin-embedded tissue. This case analysis demonstrated the utility of molecular genetics as a powerful tool for the diagnosis of atypical forms of dermatofibrosarcoma protuberans.

Cutaneous smooth muscle neoplasms: clinical features, histologic findings, and treatment options

Cutaneous smooth muscle is present in 3 separate locations: arrector pili muscles, blood vessel walls, and genital/areolar skin. Benign or malignant smooth muscle neoplasms may arise from each of these locations. This review discusses the pathogenesis, clinical manifestations, histologic findings, prognosis, treatment options, and controversial areas of cutaneous smooth muscle neoplasms. ( J Am Acad Dermatol 2002;46:477-90.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be able to discuss the pathogenesis, clinical manifestations, histologic findings, prognosis, and treatment options of cutaneous smooth muscle neoplasms.

Superficial Leiomyosarcoma of the Head and Neck: Case Report and Review of the Literature

Superficial leiomyosarcomas are rare in the head and neck region. Because of the infrequent nature of soft tissue sarcomas in general, superficial leiomyosarcomas are often misdiagnosed on clinical grounds. Immunohistochemistry is essential for an accurate histologic diagnosis, and it should include a broad panel of antibody studies. With respect to differences in clinical appearance and biologic behavior, superficial leiomyosarcomas can be broadly classified as either cutaneous or subcutaneous; local control and overall survival are significantly more favorable in patients with the former. The primary treatment of a leiomyosarcoma is a wide surgical excision with an emphasis on negative margins. Treatment failures are usually attributable to a local recurrence. Systemic metastasis occurs in about one-third of patients with subcutaneous involvement. Although cutaneous leiomyosarcoma is considered a relatively more benign process with minimal metastatic potential, systemic metastasis is still possible. This was demonstrated in our case, as a recurrent cutaneous leiomyosarcoma metastasized to the lung. Proper management requires inclusion of this entity in the differential diagnosis, as well as familiarity with its clinical behavior. In this article, we review the literature on superficial leiomyosarcoma and discuss its epidemiology, presentation, clinical behavior, evaluation, tissue diagnosis, staging, and treatment.

Dermatofibroma-like granular cell tumor

BACKGROUND

There have been several reports in the literature of dermatofibromas with granular cells. Here we report a granular cell tumor with the architecture of a dermatofibroma. This is the first report of this histological variant of granular cell tumor. The lesion was a 2.5-cm oval, hyperpigmented plaque present for "years" on the back of a 60-year-old African-American woman.

METHODS

The specimen was processed using formalin fixation and paraffin embedding. Tissue sections were stained with hematoxylin and eosin. Immunohistochemical studies were performed with antibodies directed against S-100 protein, neuron-specific enolase, and factor XIIIa.

RESULTS

Histopathologic examination revealed granular cells, some of which were spindle shaped, distributed singly and in small groups between collagen bundles resembling a dermatofibroma. Immunohistochemical studies showed the tumor cells to be positive for S-100 and neuron-specific enolase and negative for factor XIIIa.

CONCLUSION

The immunohistochemical findings support the diagnosis of a granular cell tumor with a dermatofibroma-like pattern.

Congenital CD34-positive granular cell dendrocytosis

Granular cell tumors involving the skin are mostly acquired lesions. The Schwann cell origin of these lesions is supported by positive immunostaining for S-100 protein and myelin basic protein. S-100- granular cell lesions rarely have been described in association with fibrous papules or dermatofibromas. The congenital variety of S-100- granular cell tumors occurs almost exclusively in the gingiva. The cell origin of these lesions is not well delineated. We report a hitherto undescribed case of a congenital cutaneous lesion which is histologically characterized by diffuse dermal infiltrates of S-100- but CD34+ granular dermal dendrocytes. The granular appearance of these CD34+ dendrocytes is attributed to an abundance of phagolysosomes. The pathogenetic mechanism of this unusual lesion remains to be elucidated.

Malignant granular cell tumor: report of a case and review of the literature

The histological, immunohistochemical and electron microscopic features of a rare malignant granular cell tumor (GCT) arising in the left radial nerve of a 54-year-old man are reported. Despite a lack of local recurrence following extirpation, the tumor metastasized to the skull five years later. Light-microscopically, both primary and metastatic tumors consisted of markedly atypical or pleomorphic neoplastic cells with abundant cytoplasm containing diastase-resistant periodic acid Schiff reaction-positive granules. These tumor cells were arranged in a sheet-like pattern with mitotic figures including atypical ones, and were frequently immunopositive for proliferating cell nuclear antigen and c-MET, the c-met proto-oncogene product. These findings reflect high-grade malignancy of the present tumor. In addition, the tumor cells were positive for S-100 protein and neuron-specific enolase. Ultrastructurally, a large number of intracytoplasmic granules featuring secondary lysosomes as well as long interdigitating cytoplasmic processes, intercellular intermediate junctions, discontinuous basal lamina-like structures, and stromal long-spacing collagen were observed. These findings indicated schwannian differentiation of the present tumor. In addition, based on a review of previously reported cases, the overall clinicopathological characteristics of malignant GCT were summarized.

Malignant granular cell tumor of soft tissue: diagnostic criteria and clinicopathologic correlation

Seventy-three cases of malignant, atypical, and multicentric granular cell tumors of soft tissue were studied to clarify criteria for malignancy and prognostic factors. Six histologic criteria were assessed: necrosis, spindling, vesicular nuclei with large nucleoli, increased mitotic activity (> 2 mitoses/10 high-power fields at 200x magnification), high nuclear to cytoplasmic (N:C) ratio, and pleomorphism. Neoplasms that met three or more of these criteria were classified as histologically malignant; those that met one or two criteria were classified as atypical; and those that displayed only focal pleomorphism but fulfilled none of the other criteria were classified as benign. Hence, 46 cases were classified as histologically malignant, 21 as atypical (3 were multicentric), and 6 as benign (all were multicentric). The patients with benign multicentric and atypical granular cell tumors had no metastases and there were no tumor deaths. In contrast, 11 of 28 patients (39%) with malignant granular cell tumor with follow-up information died of disease at a median interval of 3 years; 8 of 28 (29%) were alive with disease, and 9/28 (32%) were disease free (median intervals, 2 and 7 years, respectively). There were local recurrences in 9 of 28 malignant cases (32%) and metastases in 14 of 28 (50%) (median intervals, each 2 years). Forty-eight cases were studied immunohistochemically; 100% expressed vimentin, 98% S-100 protein, 98% neuron-specific enolase, 69% CD57, and 65% CD68. Alpha-smooth muscle actin, desmin, epithelial membrane antigen (EMA), cytokeratins (with CAM 5.2 and KL-1), chromogranin, and HMB45 were not detected. The proliferative index with Ki67 (MIB 1) was 10-50% in 14 of 25 malignant tumors (56%), and immunostaining for p53 was detected in 50% or more of tumor cells in 17 of 25 (68%); both of these factors were statistically significant with regard to the histologic classification as benign, atypical, or malignant. Ultrastructural examination of 13 benign, atypical, and malignant granular cell tumors showed engorgement of the cytoplasm with complex granules and lysosomes, as well as Schwannian features. By flow cytometric DNA analysis, two of six malignant tumors were aneuploid, two were hyperdiploid, and two were diploid. One atypical tumor was aneuploid and all 11 benign tumors were either diploid (9 cases) or hyperdiploid (2 cases). Statistically significant adverse prognostic factors with regard to survival included local recurrence, metastasis, larger tumor size, older patient age, histologic classification as malignant, presence of necrosis, increased mitotic activity, spindling of tumor cells, vesicular nuclei with large nucleoli, and Ki67 values greater [corrected] than 10%. This study defines clinical and morphologic criteria for malignancy in granular cell tumors and shows that malignant granular cell tumor is a high-grade sarcoma with a high rate of metastases and a short survival.

Cutaneous leiomyosarcoma in a child

Superficial leiomyosarcomas are infrequent tumors that are very rare in childhood. We report on a 12-year-old white boy with a cutaneous leiomyosarcoma of his left groin. Immunohistochemical study revealed positive immunostaining with antibodies to vimentin, desmin, and smooth muscle actin. The tumor was removed with wide surgical margins.

Granular cell dermatofibroma

We herein describe the histopathologic findings of an otherwise stereotypical dermatofibroma replete with granular cells. The histopathologic diagnosis of dermatofibroma was underlined by immunohistochemical findings and ultrastructural examination. Cellular granularity is the result of cytoplasmic accumulation of lysosomal structures and can be observed not only in conventional granular cell tumor but in a variety of benign and malignant cutaneous neoplasms. Granular cell dermatofibroma represents a hitherto undescribed variant of dermatofibroma that can be added to the broad histopathologic spectrum of this benign fibrohistiocytic proliferation.

The many faces of smooth muscle neoplasms in a gynecological sampling: an ultrastructural study

Smooth muscle neoplasms may have a variety of light microscopic and ultrastructural appearances. On one extreme, a spindle cell mass with a fascicular pattern, located in the myometrium, usually does not need electron microscopy or immunohistochemistry to confirm its smooth muscle nature. However, at the other end of a spectrum is an epithelioid neoplasm of the extrauterine pelvic tissues that could be composed of any of several cell types if routine light microscopy, alone, were used in studying it. In this report, some of these variants of smooth muscle neoplasms are exemplified, including myxomatous, fibroblast-like, nondescript, epithelioid, granular cell, and clear cell types. The main purpose has been to address, in particular, the ultrastructure of these unusual neoplasms, but, at the same time, not to ignore or downplay the contributory role of immunohistochemistry in making a final diagnosis, in some cases. Especially intriguing were the ultrastructural characteristics of leiomyomatous granular cell and clear cell neoplasms. A paucity or absence of filaments and dense bodies in samplings of these lesions makes the reliance on other ultrastructural features extremely useful.

Dermatofibroma with granular cells

A new histologic variant of dermatofibroma, only briefly alluded to in dermatological literature is reported. This tumor was located in the back of a 24-year-old man. It was present for about 2 years and had a history of trauma 2 months before excision. The lesion showed similar characteristics to those of conventional dermatofibroma as well as the presence of groups of granular cells identical to those seen in granular cell tumors. It is important to recognize dermatofibroma with granular cells because it may be confused with a variety of benign or malignant soft tissue tumors containing similar granular cells that entail different significance or prognosis. The immunohistochemical study supports a granular cell change in a dermatofibroma instead of a granular cell tumor that has been traumatized, with secondary formation of a dermatofibroma reaction.

Malignant granular cell tumor: a case report and review of the recent literature

We report a case of an extremely rare neoplasm, malignant granular cell tumor (MGCT). The tumor occurred in the infratemporal fossa of a 30-year-old man, extended to the left orbital base, into the foramen ovale, and invaded the mandible. A granular cell tumor (GCT) was diagnosed by fine-needle aspiration and core needle biopsy of the mass. The patient underwent a radical subtotal debulking procedure followed by radiotherapy. He is alive with recurrent disease 12 months after presentation. Cytologically, the aspirated material was abundantly cellular showing large polygonal cells with ample granular eosinophilic cytoplasm, eccentric nuclei, and often prominent nucleoli. Histologically, the tumor consisted of solid sheets of similar cells that stained strongly with S-100 protein, neuron-specific enolase (NSE), and vimentin. There was moderate nuclear pleomorphism and broad zones of necrosis. Four mitotic figures per 100 high-power field (HPF) were counted. By electron microscopy, the cytoplasm of the tumor cells was filled with lysosomes. Although, some observers advocate that the diagnosis of a MGCT should be reserved for cases in which lymph node and/or distant organ metastasis is evident, we believe malignancy ought to be considered in any GCT with aggressive clinical course defined by persistent local recurrence and destruction of neighboring structures. Nuclear pleomorphism, necrosis, and presence of any mitotic activity should indicate malignancy.

Granular cell change in smooth muscle tumours of skin and soft tissue

Nine smooth muscle tumours, arising at a variety of sites and showing granular cell change of their cytoplasm, have been studied morphologically and immunohistochemically. The age of the patients ranged from 6 to 78 years (median 42 years); seven patients were female. Two tumours each arose in the dermis or subcutaneous tissue while the other five cases were situated in deeper soft tissue. Three of the lesions arose in the lower limbs, two in the pelvis and one each in the regions of the elbow, shoulder, breast and buttock. Follow-up in eight patients was available and revealed local recurrence in three and pulmonary metastases in two cases. All cases showed at least focally the light microscopic features of a smooth muscle tumour and demonstrated moderate to strong positivity for alpha-smooth muscle actin. Five were also HHF-35 positive and three were desmin positive. Noteworthy was strong positivity for the 'melanoma associated' antigen NKI/C3 in all cases. Six cases stained also weakly positive for NSE, but all were S-100 protein negative. The former is not specific but is the most reliable marker of lesions showing granular cell change. Granular cytoplasmic change represents simply a cytological phenotype, apparently representing a characteristic metabolic alteration, not exclusively associated with Schwann cell tumours. Tumours containing granular cells are best classified according to their line of specific cellular differentiation if possible.

Granular cell basal cell carcinoma. Light microscopy, immunohistochemical and ultrastructural study

Granular cell basal cell carcinoma (BCC) is a rare histological variant of BCC. In this, the fifth reported case, a 67-year-old male with BCC located on the nose, light microscopy examination showed a tumour with the classical configuration of nodular BCC, in which most cells had finely granular eosinophilic cytoplasm. Ultrastructural observation showed numerous lysosome-like granules filling the cytoplasm of tumour cells, along with numerous well-formed pentalaminate desmosomes. Immunohistochemical profile (including positivity for keratins C 5.2 and AE 1 and for Leu-M1), together with the presence of cytoplasmic tonofilament bundles and desmosomes, are consistent with the proposed epithelial origin of granular cells in this tumour.

Histologic and immunohistochemical studies of granular cell tumors in seven dogs, three cats, one horse, and one bird

In a retrospective study, granular cell tumors in six dogs (Nos. 1-6), three cats (Nos. 1-3), one horse (No. 1), and one cockatiel (Nymphicus hollandicus) (No. 1) and a meningioma with a granular cell component in one dog (No. 7) were examined histologically and immunohistochemically. These tumors were identified by histologic examination of surgical biopsy specimens, except in the horse, in which the tumor was an incidental finding at necropsy. These diagnoses were initially made by more than one pathologist. Five of the six granular cell tumors in the dogs were in the oral cavity; one of these was in the maxillary gingiva of a 6-month-old puppy. The tumors in the cats were located in the tongue, vulva, and digit. The tumor in the horse was in the lung, and the tumor in the cockatiel was in the periocular tissue. Histologically, all granular cell tumors were characterized by oval to polygonal cells of various sizes. The cells had abundant, pale, eosinophilic cytoplasm with distinct intracytoplasmic granules, distinct cell margins, and mostly central nuclei. In the dogs, the gingival tumor had a large amount of collagen tissue, the tumor in the tongue had dilated blood vessels, and the maxillary tumor in the puppy was more cellular than the other tumors. The tumors in the cats were more anaplastic than the other tumors; one, located in the digit, was considered malignant. The granules in all of the tumors stained with periodic acid-Schiff and were diastase resistant. On staining with Luxol fast blue, the granules of all tumors stained different shades of pink, with the exception of the tumor in the tongue of a cat, which stained bluish green. Immunocytochemically, all tumors except the tumor in the cockatiel reacted against antibodies to vimentin. The granular cell tumor in the lung of the horse and the intracranial meningioma in a dog reacted to the antibody S-100 protein; the tumor in the horse reacted to neuron-specific enolase; tumors in two dogs (gingiva and skin) reacted to L-antitrypsin, and the maxillary tumor also reacted to lysozyme; the malignant tumor in the digit of a cat and the periocular tumor in the cockatiel reacted to muscle common actin and actin; the tumor in the cockatiel also reacted to desmin. Results of these immunocytochemical studies suggest that granular cell tumors, like tumors composed of rhabdoid cells, clear cells, and oncocytes, can have similar morphologic features but be of different cellular origins.

Leiomyoma exhibiting a marked granular change: granular cell leiomyoma versus granular cell schwannoma

Granular change of leiomyoma or granular cell leiomyoma is rare and not well recognized. It may be confused with the common variety of granular cell tumor, which is currently regarded as being of schwannian origin. A case of granular cell leiomyoma in the periurethral region of a 40-year-old woman is reported. Microscopy indicated that the tumor consisted of polygonal or fusiform cells with coarse, granular eosinophilic cytoplasm. Immunohistochemically, the tumor cells were positive for desmin and actin, but negative for neuron-specific enolase and S-100 protein. Electron microscopy revealed myofilaments in the tumor cells, thus documenting the myogenic origin of the granular cells. The granules were ultrastructurally similar to those of granular cell schwannoma as described in the literature. It is likely that granular cell tumor arises from different tissues.

Leiomyosarcoma of somatic soft tissues in childhood: an immunohistochemical analysis of six cases with ultrastructural correlation

Leiomyosarcoma (LMS) of soft tissue is a rare tumor in children. Although LMS may exhibit clinical and histologic features that are typical of smooth muscle neoplasms in adults, they may often be confused with or resemble tumors of presumed fibroblastic, myofibroblastic, or rhabdomyoblastic differentiation. As a result, the diagnosis of LMS in children is often difficult to establish with confidence. To address this problem, we analyzed the immunohistochemical features of six LMS in children (one of deep soft tissue of an extremity, one of paravertebral tissue, one of the retroperitoneum, two of oropharyngeal soft tissue, and one of subcutis); the ultrastructural features of four of these tumors were also studied. Histologically, each of the three tumors of deep soft tissue and one of the retromolar trigone were composed of pleomorphic spindle cells arranged in interweaving fascicles. In contrast, the subcutaneous tumor and the lesion of the hard palate had an epithelioid appearance. Ultrastructural features were typical of adult type LMS. Immunohistochemically, these neoplasms were diffusely reactive for vimentin, while each was negative for cytokeratin, epithelial membrane antigen, and S-100 protein. Desmin was present in all cases, but was expressed only focally in three; a similar pattern of staining was noted for muscle-specific actin, although staining was generally noted in a larger population of cells. alpha-1-Antichymotrypsin was found in five tumors, and cathepsin B reactivity was encountered in four cases. Leu-7 antigen and myelin basic protein were coexpressed by one tumor, but neither was found in the remaining cases. These results indicate that immunohistochemical detection of desmin and muscle-specific actin may be useful in the differential diagnosis of spindle or epithelioid cell proliferations in childhood when ultrastructural analysis in unavailable.

Metastatic breast carcinoma mimicking granular cell tumor

Metastatic breast carcinoma may assume many patterns. We describe a case in which cutaneous, pulmonary and lymph node metastases of an adenocarcinoma of the breast all resembled granular cell tumor. In all sites, the lesion stained positive with antibodies against EMA and cytokeratins, but failed to stain with anti-S100.