Flow cytometric DNA content analysis of a case of pilomatrix carcinoma showing multiple recurrences and invasion of the cranial vault

Pilomatrix carcinomas are rare neoplasms of the skin that may be locally aggressive or metastatic. The differentiation of these tumors from benign pilomatrixomas depends on a constellation of microscopic features, some of which may be equivocal or absent in individual biopsy specimens. We encountered a tumor with distinct pilomatrix differentiation (lobulated nests of basaloid cells, ghost cells, focal calcification) that recurred multiple times and ultimately invaded the cranial vault. Despite this aggressive behavior, the tumor was difficult to separate from benign pilomatrixoma on morphologic grounds. Because DNA content flow cytometry has proved useful in the prediction of aggressive behavior in various solid tumors, we analyzed this neoplasm by flow cytometry. Neither aneuploid peaks nor a high proliferative fraction were seen in this example of pilomatrix carcinoma.     

Two cases of pilomatrixoma in Turner's syndrome

Multiple and familial cases of pilomatrixomas have been reported in myotonic dystrophy. We report 2 cases of pilomatrixoma in Turner's syndrome. Between 5 and 19 years of age, 1 patient developed 6 pilomatrixomas including atypical occurrences on the chest and the posterior aspect of the leg. This is the first report of multiple pilomatrixomas in Turner's syndrome. Copyright (R) 2000 S.Karger AG, Basel     

Mitotic granuloma annulare: a clinicopathologic study of 20 cases

The finding of mitotic figures in granuloma annulare (GA) has not been emphasized in the literature. We describe 20 cases of a cellular, mitotically active variant of GA; we defined this group as cases having ≥ 1 mitosis per 10 hpf. Clinically, the lesions could not be distinguished from typical, localized GA: there were 9 males and 11 females with a mean patient age of 49±15 years (mean±SD), compared to 45±20 years in a randomly selected control group of 60 patients with GA, and no unusual sites of predilection were noted. Histologically, a classic, palisading granuloma pattern predominated (18/20 cases). Lesions were located in the mid-dermis and tended to be more cellular than typical GA. The histiocytes comprising the lesion often had enlarged nuclei and prominent nucleoli. The number of mitoses per 10 hpf was 3.0±1.5 (range 1.0–7.2), control group 0.3±0.5; occasional atypical mitotic figures were observed. The proliferative nature of these lesions was confirmed using MIB-1 staining; the percentage of MIB-1 positive cells ranged from 5%–29% (mean 15±6%). Mitotic GA must be distinguished histologically from neoplastic processes, in particular epithelioid sarcoma. We conclude that histiocytes in clinically typical GA can exhibit an increased mitotic rate. Recognition of this variant is important in order to avoid overdiagnosis of a malignant condition.     

Use of ultrasonography in the diagnosis of childhood pilomatrixoma

Pilomatrixomas are relatively common childhood tumors that usually occur in the head and neck region. The clinical diagnosis of these lesions may be difficult, especially if the examining physician is unfamiliar with them. Excision is usually recommended, as a foreign body reaction due to calcification of the lesion may occur and cause a vigorous inflammatory response with risk of scarring. A retrospective study was carried out by examining the preoperative ultrasound scans of 28 suspected pilomatrixomas in 25 children. The findings on sonography were correlated with the histologic results in 19 cases (18 pilomatrixomas and one ruptured epidermoid cyst). In the majority of patients, sonography either correctly supported or excluded the clinical diagnosis of pilomatrixoma and contributed to appropriate preoperative assessment and subsequent management of the lesion. We therefore found sonography of suspected pilomatrixomas in children to be a useful and noninvasive procedure, offering a significant improvement in the accurate diagnosis of these lesions.     

Factors predictive of recurrence of basal cell carcinoma

Thirty recurrent basal cell carcinomas were compared with 74 nonrecurrent basal cell carcinomas to identify clinical and histologic features predictive of recurrence. Three clinical parameters were evaluated: age, duration, and location; only location proved to be of prognostic significance. Among the histologic parameters, statistically significant differences between the recurrent and nonrecurrent groups were found in: measured distance to the resection margins, shape of cell groups, growth pattern, contour of invading edge, and degree of peripheral palisading and nuclear pleomorphism. Degree of fibrosis, cystic change, and atypical squamous change were of possible prognostic significance. There were no statistically significant differences between the two groups regarding: measured depth of invasion and diameter, degree of inflammation, actinic change, tumor necrosis, nuclear hyperchromasia, nucleoli, mitoses, amount of melanin or amyloid, and size of cell groups. Based on histologic findings, the pathologist may in many cases be able to suggest to the surgeon which tumors are more likely to recur and therefore require more aggressive therapy.     

Hair Matrix Differentiation in a Trichogenic Adnexal Neoplasm.

We have reviewed sixteen patients with the diagnosis of desmoplastic Spitz nevus. The age of our patients ranged between seven years and fifty‐four years. We noted a predominance of twelve female patients and four male patients. Histologically, ten of the sixteen cases were well circumscribed and symmetric. In six cases we were unable to ascertain the overall architectural features because of the biopsy technique. Only three cases showed significant junctional melanocytic nesting. In five cases there were rare nests of melanocytes at the dermo‐epidermal junction and in eight cases there was no evidence of melanocytic nesting at the dermo‐epidermal junction. Dermal mitotic figures were rare, with five cases showing a single dermal mitotic figure. The lesions did not arise in sun damaged skin as evidenced by the rarity of actinic elastosis within our specimens. Additional clinical and histologic findings and follow up will be reported.     

Cutaneous papillary squamous cell carcinoma. A report of two cases

Several histologic patterns of squamous cell carcinomas (SCC) have been described, including classical, adenoid, verrucous, and clear cell. We report 2 cases of an unusual purely exophytic papillary growth pattern. Both tumors occurred on sun-exposed skin of elderly patients and exhibited rapid growth. The tumors were red-tan and fungating, raising the clinical differential diagnoses of pyogenic granuloma, SCC, metastatic carcinoma or amelanotic melanoma. Histologically there was a prominent papillary growth pattern with several layers of notably atypical squamous epithelium overlying a fibro-vascular core in both cases. Mitoses were frequent. The tumors lacked deep invasion, although focal invasion of the stalk was present. These tumors were histologically distinct from verrucous carcinoma, verrucous Bowen's disease, and previously described adnexal carcinomas. The lack of deep invasion and the absence of local recurrence or metastatic disease after 18 months follow-up suggest that this histologic variant is a low-grade malignancy, although study of more cases and longer follow-up will be necessary to accurately assess the biology of this papillary variant of SCC. We believe that this growth pattern has not yet been described and a pure papillary form must be included as one of the histological subtypes of cutaneous SCC.     

Pilomatrical carcinosarcoma of the temple: A case report

Pilomatrical carcinosarcoma is a very rare entity, with only six cases reported until now. This report describes the case of a 100‐year‐old woman with a mass on the left temple that had existed for several decades but had recently grown in size. Histology showed an asymmetric lesion composed of basaloid cells, spindle cells, and “shadow” or “ghost” cells. Cells had atypical hyperchromatic nuclei with prominent nucleoli, high mitotic activity, and atypical mitosis. In the central area, an epidermal cyst‐like structure was seen. The diagnosis of pilomatrical carcinosarcoma was rendered. This case appeared to have arisen from malignant transformation of a pilomatricoma because of the long clinical history and existence of a benign epidermal cyst‐like structure. In addition, the observation that the basaloid cells and spindle cells showed a gradual transition from one to the other and that both types were positive for β‐catenin would seem to support a common clonal origin for the carcinomatous and sarcomatous components.     

Melanocytic matricoma with melanocytic atypia: report of a unique case and review of the literature

Melanocytic matricoma is a rare cutaneous neoplasm of presumed anagen hair follicle origin with approximately 10 reported cases in the literature. Melanocytic matricomas are clinically and histopathologically distinct cutaneous nodular proliferations of matrical and supramatrical cells admixed with dendritic melanocytes, which typically occur in the sun-exposed areas of elderly patients. We report a new case with additional histopathologic features not previously described. An 82-year-old white man presented with an exophytic papule of the ear clinically suspicious for basal cell carcinoma. Histopathologic examination demonstrated a polypoid neoplasm consisting of an admixture of matrical and shadow cells with numerous interspersed dendritic and epithelioid melanocytes arranged singly and in large expansile nests. An unusual feature in this case included prominent melanocytic proliferation with associated nuclear atypia and increased mitotic activity. Although atypical and malignant melanocytic colonization has been reported in basal cell carcinomas and squamoproliferative lesions, to our knowledge, it has not been previously described in melanocytic matricomas. The biologic significance of atypical melanocytic proliferations within melanocytic matricomas is uncertain and requires further study of additional cases and long-term follow-up.     

Angiosarcoma in a chronically immunosuppressed renal transplant recipient: report of a case and review of the literature

Angiosarcomas are rare malignant tumors of endothelial origin that occur predominantly in the adult population. To date, only 12 cases have been described after renal transplantation. We review the literature and present an additional case of a 59-year-old patient in whom lower-extremity lesions of cutaneous angiosarcoma developed several years after transplantation. Of the 13 patients, clinical details were available in only 12 cases. There were 10 male and 2 female patients. The mean age at diagnosis was 47.6 years (age range, 28-71 years). Almost all patients were on a combination immunosuppressive regimen, and the interval between transplantation and the development of the tumor was variable in the range of 8 months to 12 years. In five patients, the tumor arose within or adjacent to an arteriovenous fistula site. Cutaneous involvement was observed in only four cases. The histologic spectrum consisted of both well-differentiated and poorly differentiated tumors. In one patient, features of the hemophagocytic syndrome were clinically present and the tumor morphologically displayed prominent erythrophagocytosis. In two of the cases, including the patient described in the current report, polymerase chain reaction was performed on lesional tissue for human herpesvirus-8 and the result was negative for the presence of viral DNA. Despite the use of multimodal aggressive therapy in most patients, death as a result of disease dissemination occurred over variable time periods (range, 1-15 months).     

Malignant cutaneous glomus tumor presenting as a rapidly growing leg mass in a pregnant woman

A 21-year-old pregnant woman presented with a rapidly growing >2 cm nodule on her right leg, involving dermis and subcutaneous tissue. Histologically, the tumor was composed of sheets and nests of neoplastic cells with variable cytomorphology, including typical round to ovoid glomus cells with clear cytoplasm and well-defined cell borders, small cells and spindle cells. Numerous medium to large vessels were present throughout the tumor. Moderate- to high cellularity, nuclear atypia and frequent mitotic figures (42 MF/50 High power field (HPF)) were noted. Immunohistochemistry showed cytoplasmic and membranous expression of actin (HHF-35) and membranous expression of type IV collagen. The histologic features and immunoprofile were consistent with the diagnosis of malignant glomus tumor, a rare soft tissue neoplasm that typically arises on the extremities. Histologic features that infer malignancy in glomus tumors include the combination of large size (>2 cm) and deep location, or atypical mitotic figures, or moderate to severe cytologic atypia with high mitotic activity (>5 mitoses /50 HPF). Although our case was superficially located, the nuclear atypia and mitotic rate, as well as the large size, fulfilled the criteria for a malignant glomus tumor.     

Granular cell atypical fibroxanthoma: case report and review of the literature

We present a case of granular cell atypical fibroxanthoma of the scalp. The neoplasm occurred as a tender nodule on the frontal scalp of an 82‐year‐old Caucasian man. Histology demonstrated a diffuse proliferation of atypical epithelioid cells with abundant granular cytoplasm. Many of the cells had large irregular nuclei and atypical mitotic figures were present. Immunohistochemical stains were positive for CD68 and procollagen 1 and negative for cytokeratin, HMB‐45 and S‐100 protein. The granular cell phenotype has been observed in other cutaneous neoplasms including granular cell tumors, dermatofibromas, dermatofibrosarcoma protuberans, fibrous papules, basal cell carcinomas, leiomyosarcomas, angiosarcomas and primitive polypoid granular cell tumors. We discuss the differential diagnosis and review the previously reported cases of this rare variant of atypical fibroxanthoma. Wright NA, Thomas CG, Calame A, Cockerell CJ. Granular cell atypical fibroxanthoma: case report and review of the literature.     

Proliferating pilomatricoma

We report on 9 patients with pilomatricomas that showed unusual histopathologic features. Our patients were mainly elderly individuals (age range 42 to 88 years; mean age 70.1 years) who presented solitary cutaneous nodules situated on the head and neck (7 neoplasms), upper arm (1 neoplasm), and back (1 neoplasm). All the lesions were treated by simple excision. Follow-up data available in 7 of the 9 patients (mean follow-up, 17 months) revealed local recurrences in 1 patient whose lesion recurred 3 times. No lymph node involvement or distant metastases were recorded in any of our cases. Histopathologically, most neoplasms were characterized by a relatively large lesion in the clermis that in some cases showed extension to the subcutis. Each lesion was predominantly composed of a lobular proliferation of basaloid cells in association with adjacent focal areas containing eosinophilic, cornified material with shadow cells. In some cases, relatively large areas of shadow cells were present, whereas, in others only small foci of shadows cells were observed. Cytomorphologically, the basaloid cells showed features of matrical and supramatrical cells of a normal hair follicle and exhibited variable nuclear atypia and mitotic figures. The overall architectural pattern of the neoplasms was different from that of large fully developed stereotypical pilomatricomas that maintain a cystic character with basaloid cells predominantly aligned at the periphery. Based on the histopathologic findings, namely the presence of a large, lobular proliferation of basaloid cells in association with small to large foci of shadow cells, we interpreted these neoplasms to be a distinctive proliferative variant of pilomatricoma and propose the designation "proliferating pilomatricoma." Proliferating pilomatricomas should be differentiated from the recently described matricoma, basal-cell carcinoma with matrical differentiation, and matrical carcinoma (pilomatrical carcinoma).     

CRTC1‐TRIM11 fusion defined melanocytic tumors: A series of four cases

A cutaneous melanocytic tumor with morphologic overlap with clear cell sarcoma, but defined by CRTC1‐TRIM11 gene fusion, was recently described in a series of five adult patients. Here, we expand the clinicopathologic features of this entity by four additional cases which include pediatric presentation, exophytic growth, and propensity to occur on the head. Patients (2F; 2M) had a median age of 41 years (range 11‐59). Sites of involvement included leg, ear, and face. Tumors were circumscribed, unencapsulated, mostly limited to the dermis, and varied from 5 to 35 mm. One case was exophytic. Lesional cells were arranged in nests and fascicles, and were monomorphic and fusiform with moderate pale to clear cytoplasm, occasional nuclear pseudo‐inclusions, and small to prominent nucleoli. Mitotic rate was variable (rare to 12/10 HPF, median 3/10 HPF). The pediatric case showed increased nuclear pleomorphism, tumor necrosis, and mitotic figures. All cases showed strong, diffuse nuclear staining for SOX10, but were negative or focal for S100 protein, HMB45 and Melan‐A expression. Cases were positive by FISH technique and/or RNA sequencing for a TRIM11 rearrangement/fusion, and negative for EWSR1 rearrangement. This series is presented to aid in further characterization of this novel melanocytic tumor.     

Glomangiosarcoma of the hand: a case report and review of the literature

Glomangiosarcomas, or malignant glomus tumors, are very rare, cutaneous, soft tissue tumors. Despite having histologic features of malignancy, these tumors usually do not metastasize. We describe a 74-year-old woman with a glomangiosarcoma on her hand and review the literature. The woman presented with a five month history of a painful mass on the right palm. An excisional biopsy of the mass was undertaken. Histologically, the tumor was composed of uniform, round cells and numerous vascular components. The tumor cells were pleomorphic and had large nucleoli. Frequent mitotic figures were identified. Immunohistochemical stains showed strong positivity for vimentin and weak, focal positivity for smooth muscle actin. Ultrastructurally, the tumor cells were characterized by pinocytic vesicles, well formed basal lamina, and scattered junctional complex of the plasma membrane.     

Malignant transformation of eccrine spiradenoma

Two patients are described in whom malignant transformation occurred within an eccrine spiradenoma. Their findings were compared with those of six similar patients from the literature, and a characteristic clinicopathologic picture was evident. The typical history was one of rapid enlargement of a cutaneous nodule of long standing. The neoplasms were composed, at least in part, of large, markedly atypical basaloid cells with numerous mitotic figures. Adjacent benign spiradenoma was observed microscopically in each case, and some of the carcinomas retained architectural features reminiscent of spiradenoma. One patient died of disseminated tumor, but follow-up was short or lacking in several cases. Malignant transformation of eccrine spiradenoma shares many clinical and pathologic features with malignant transformation of dermal cylindroma.     

A skin tumor from an orthopedic oncology perspective: Pilomatrixoma in extremities (11 years experience with 108 cases)

Pilomatrixoma, also known as calcifying epithelioma of Malherbe, is a benign skin neoplasm originating from hair follicle matrix cells. Pilomatrixoma is a common skin neoplasm that is often misdiagnosed as another type of skin condition. The aim of our study is to review 11 years' worth of experience in examining clinical and histopathological presentations, imaging findings, management approaches, and treatment outcomes of pilomatrixoma at a tertiary hospital. A review of the pathology database revealed that 108 extremity pilomatrixomas were excised between 2007 and 2018. Hospital charts, and pathology and orthopedic clinic records, were reviewed for patient data such as age, gender, clinical and histopathological presentations, preoperative diagnosis and imaging results, management approach, recurrence, and treatment outcomes. The main presenting symptom was a hard, subcutaneous, slowly growing mass. The preoperative diagnosis was accurate and consistent with the pathological diagnosis of pilomatrixoma in only 35 cases (32%). The optimal diagnostic tool for pilomatrixoma seems to be ultrasound imaging of superficial tissue, and the optimal first‐line treatment might be surgical excision with clear margins. However, pilomatrixoma is a benign tumor, with atypical forms, and there no tumor‐specific diagnostic tool is available other than careful histopathological examination.     

The Histopathologic Differentiation of Keratoacanthoma and Squamous Cell Carcinoma of the Skin

The classification of skin tumors as keratoacanthoma or squamous cell carcinoma may be difficult and, albeit rarely, lesions classified as keratoacanthoma do metastasize. In order to review the reproducibility of the pathologic classification, 100 keratoacanthomas and 100 squamous cell carcinomas of the skin were randomized and reclassified. In 81% of the keratoacanthomas and 86% of the squamous carcinomas the original diagnosis was confirmed. The presence or absence of 10 histologic criteria was recorded for all cases. Almost all of the confirmed keratoacanthomas had invaginating keratin-filled craters with epidermal proliferation at the sides and the bottom of the lesion and significant atypia and mitotic activity was rare. Most of the confirmed squamous cell carcinomas showed considerable cellular anaplasia and pleomorphism and many displayed significant mitotic activity. It is concluded that a definite diagnosis of keratoacanthoma or squamous cell carcinoma can be made objectively on histologic grounds but that some tumors are atypical or borderline lesions which must be indicated in the pathologic report.