Eosinophil‐rich trichoblastic carcinoma with aggressive clinical course in a young man

We present the case of a 35‐year‐old man who developed a follicular differentiated cutaneous carcinoma with an eosinophil‐rich infiltrate and an aggressive clinical behavior. After an in‐depth histopathological investigation the diagnosis of trichoblastic carcinoma was made. Over the course of the disease the patient developed a cutaneous in‐transit metastasis as well as an axillary lymph node metastasis 18 months after the excision of the primary tumor on his back. Based on a literature review we discuss the different concepts behind the term “trichoblastic carcinoma” and we summarize the clinical and histological details of previously reported cases. Furthermore, we focus on the phenomenon of tumor‐associated eosinophilia.     

Panniculitic T-cell lymphoma

Panniculitic T-cell lymphoma is a rare, aggressive variant of cutaneous T-cell lymphoma, with fewer than 100 cases described. The main problem is its diagnosis, as both the clinical and the histological features may simulate benign panniculitis. We present the case of a 34-year-old male patient, who had presented with an indurated plaque, sclerodermiform in appearance, on the front of the right thigh for 4 months, later accompanied by fever and constitutional symptoms. The initial diagnosis was cellulitis, but no clinical improvement was seen despite systemic antibiotic therapy. After two skin biopsies, the patient was diagnosed with panniculitic cutaneous T-cell lymphoma. The patient was treated with 8 cycles of CHOP chemotherapy, with resolution of the symptoms.     

Unilesional mycosis fungoides: a study of seven cases

BACKGROUND: Unilesional mycosis fungoides (MF) is a rare variant of cutaneous T-cell lymphoma (CTCL), characterized by a solitary lesion clinically and by histopathological features indistinguishable from those of MF, and typically having a benign course. OBJECTIVE: To describe the clinicopathological features of a series of patients with unilesional MF. METHODS: The records of cases of unilesional MF identified during a 10-year period in two medical departments were reviewed. RESULTS: There were 7 patients: 6 males, 1 female; mean age at the time of diagnosis: 32 years; age range: 12-58 years; 3 were below the age of 18 years. The mean pretherapy follow-up period was 9 years (range: 2-20 years). In 5 patients, the eruption consisted of a characteristic patch or plaque of MF located on the trunk or upper extremity; in 2 it was atypical - in 1, a hypopigmented patch, and in 1, a plaque indistinguishable from MF-associated follicular mucinosis. Histopathologically all the lesions exhibited features characteristic of MF, with CD3+ lymphoid cells. In 6 cases (with available fresh frozen tissue) there was a predominance of CD3+ CD4+ cells; in 1 of 5 there was deletion of CD7, and in 3 of 5 there was an overexpression of IL-2 receptor. T-cell receptor gamma gene rearrangement was found in 1 of 4 cutaneous lesions tested; in 2 cases it was found in the blood but not in the skin. Treatment modalities included localized electron beam, excision, topical nitrogen mustard or topical steroids and sunbathing, resulting in all cases in a sustained complete clinical response. In 1 patient, however, there were 2 local recurrences and in yet another patient there was distant cutaneous spread 3.5 years after therapy. CONCLUSIONS: Unilesional MF is a rare variant of CTCL, has heterogeneous clinical manifestations and can affect any age group, including children. The histopathological and immunophenotypical features are in general indistinguishable from those observed in multilesional MF. Although it is a unifocal event, there may occasionally be cutaneous spread with the appearance of noncontiguous lesions, even a long time after therapy. Whether all cases represent minimal-stage IA MF or whether some are actually T-cell pseudolymphoma remains to be clarified.     

Genital leiomyomas of the male nipple: two cases

BACKGROUND: Genital leiomyoma is a rare benign solitary skin tumor, not painful, developed from smooth muscle. Genital leiomyoma arising from the nipple is extremely rare, especially in males.CASES REPORT: A 47 year-old male had a 2 cm cutaneous plaque with nodules located on the right nipple. This plaque was circumscribed, erythematous, pruriginous and was not painful. The lesion had been noticed by the patient two years ago. A 37 year-old male showed a 1.5 cm cutaneous plaque located on the left nipple. The plaque was slightly erythematous, pruriginous, not painful and had been noticed by the patient 5 years earlier. Histology provided the diagnosis of genital leiomyoma in both cases. No surgical therapy was performed.DISCUSSION: Cutaneous leiomyomas are classified in 3 types regarding their origin: multiple or solitary piloleiomyoma, arising from arectores pilorum muscles, solitary genital leiomyoma, arising from the dartoic, vulvar, or mammillary muscles, and solitary angioleiomyoma, arising from the vein muscles. Clinically, genital leiomyoma is a 1 cm diameter solitary erythematous, firm nodule. According to many authors, genital leiomyoma is asymptomatic, but in the 2 patients, the lesions were pruriginous. Surgical excision is usually performed.     

Trichoblastic fibroma. A clinicopathologic study of three cases

Three cases of trichoblastic fibroma, a rare benign skin tumor of hair follicle origin, are reported. On clinical examination, solitary, mobile, subcutaneous nodules with normal overlying skin were found on the vulva (one case) and scalp (two cases) in women aged 57, 46, and 19 years, respectively. On microscopic examination, the tumors were composed of complex nests and strands of basaloid, focally keratinized epithelium arranged in a moderately cellular fibroblastic stroma. No connection with the overlying epithelium or adjacent adnexal structures was observed. Immunohistochemical staining supported a trichogenic origin for these tumors. Trichoblastic fibromas are histologically distinctive lesions that should be distinguished from other tumors of follicular origin and from keratotic basal cell carcinoma.     

Perifollicular fibroma in Birt-Hogg-Dubé syndrome: an association revisited

Background: Mutation in the folliculin gene in Birt–Hogg–Dubé (BHD) syndrome leads to a spectrum of benign tumors of the hair follicle, classically including both fibrofolliculoma and trichodiscoma. In addition, lesions clinically indistinguishable from fibrofolliculoma/ trichodiscoma may show histopathologic findings of perifollicular fibroma or angiofibroma. Although some consider perifollicular fibroma to be a variant of angiofibroma, the specific histopathologic findings of perifollicular fibroma are uncommon. Methods: This is a case series. Results: In 4 patients with multiple facial lesions, recognizing perifollicular fibroma would have been helpful in leading to the diagnosis of BHD syndrome. Conclusion: Perifollicular fibroma is on a spectrum with fibrofolliculoma and trichodiscoma; in a patient with multiple lesions, the diagnosis of perifollicular fibroma is suggestive of BHD syndrome.     

Brooke-Spiegler syndrome: report of a case with combined lesions containing cylindromatous, spiradenomatous, trichoblastomatous, and sebaceous differentiation

Brooke-Spiegler syndrome is an autosomal dominantly inherited disease with predisposition to cutaneous adnexal neoplasms, most commonly cylindromas and trichoepitheliomas. We report a patient in whom 11 lesions were removed from the scalp and face for various reasons over a period of 3 years. The histopathological survey revealed a plethora of benign adnexal neoplasms showing apocrine, follicular, and sebaceous differentiation occurring independently and conjointly. The histopathological spectrum in our patient included cylindromas, spiradenomas, trichoepitheliomas, small nodular trichoblastomas, and lymphadenomas. Many lesions had hybrid features of two or more neoplasms. By far the most common composite tumor was spiradenocylindroma. Some spiradenocylindromas demonstrated prominent sebaceous or trichoblastomatous differentiation or both. We suggest the terms "sebaceous spiradenocylindroma" and "trichospiradenocylindroma" for these lesions. The occurrence of sebaceous and trichoblastic differentiation in spiradenocylindromas is a further proof that spiradenoma and cylindroma are not eccrine tumors but neoplasms of the folliculosebaceousapocrine unit.     

High‐grade trichoblastic carcinoma arising through malignant transformation of trichoblastoma: Immunohistochemical analysis and the expression of p53 and phosphorylated AKT

Trichoblastoma (TB) is a benign cutaneous adnexal neoplasm. The lesion typically presents as a slow‐growing, solitary, well‐circumscribed nodule measuring up to 3 cm in diameter. On rare occasions, TB causes malignant transformation into an aggressive form described as high‐grade trichoblastic carcinoma. Four such cases have been reported to date; all were described as high‐grade trichoblastic carcinomas. Here, we describe the case of a 72‐year‐old Japanese male patient with a rapidly enlarging subcutaneous tumor on his lower back, which was diagnosed as high‐grade trichoblastic carcinoma. Histopathologically, the tumor featured both benign and malignant components, and a transition zone between these states was clearly evident. In the immunohistochemical analysis, a malignant component was positive for p53 and showed stronger staining of phospho‐RAC‐α serine/threonine‐protein kinase (AKT) Ser473 in comparison with a benign component. These results suggest that loss of p53 function and activation of phosphatidylinositol 3‐kinase–AKT signaling pathways played important pathogenic roles in malignant transformation of the present case.     

A rare case of atypical cellular neurothekeoma in a 68-year-old woman

Cellular neurothekeoma is a benign dermal lesion of uncertain differentiation. The atypical variant of cellular neurothekeoma, characterized by features such as large size, deep penetration, diffusely infiltrative borders, vascular invasion, high mitotic rate and marked cytologic pleomorphism, has been very rarely reported in the literature. We present the clinical, histopathological and immunohistochemical profile of a new case of atypical cellular neurothekeoma in a 68-year-old female patient who was diagnosed with ductal breast carcinoma in situ before. An erythematous painless papule arose in her right breast, and tentative clinical diagnosis was orientated toward skin metastasis of breast cancer or fibroma. Upon histological examination, the lesion showed the histological and immunohistochemical features of atypical variant of cellular neurothekeoma with high mitotic rate, marked cellular pleomorphism and penetration into subcutaneous fat. A further unusual feature in our patient was her age, because she is the oldest patient reported in the literature with diagnosis of atypical cellular neurothekeoma so far. Prognosis remains uncertain because only few cases of atypical cellular neurothekeoma have been reported in the literature, with a very limited follow-up time. Our report contributes to a better characterization of the clinical and morphologic features of atypical cellular neurothekeoma.     

Hypocellular Plaque‐Like CD34‐Positive Dermal Fibroma (Medallion‐Like Dermal Dendrocyte Hamartoma) Presenting as a Skin‐Colored Dermal Nodule

Plaque‐like CD34‐positive dermal fibromas, also known as medallion‐like dermal dendrocyte hamartomas (MDDHs), are a recently recognized group of congenital and acquired spindle cell neoplasms that may appear histologically similar to dermatofibrosarcoma protuberans. Recognizing the clinical heterogeneity of this neoplasm and the subtle pathologic differences are crucial to making the correct diagnosis and avoiding the aggressive surgical intervention required to treat a dermatofibrosarcoma protuberans. We present the case of a 9‐year‐old girl with an acquired variant of a plaque‐like CD34‐positive dermal fibroma without clinical epidermal change. Our case expands the clinical spectrum to include an acquired variant of a plaque‐like CD34‐positive dermal fibroma without clinical epidermal change. Examination of more cases is needed to determine whether all clinical variants are truly subtypes of the same neoplasm or represent distinct CD34‐positive spindle cell proliferations.     

Subungual pleomorphic fibroma

BACKGROUND: Pleomorphic fibroma is a benign fibroblastic tumor characterized by pleomorphic, hyperchromatic cells or giant multinucleated cells embedded in a collagenous stroma. These cytologic features may lead to an incorrect diagnosis of malignancy. Most cases reported in the literature are located on trunk or extremities; the presentation as a subungual mass is rare. METHODS: We report an unusual case of a subungual pleomorphic fibroma in 66-year-old woman. Clinical information was obtained. Histologic examination and immunohistochemical studies were performed. RESULTS: A 66-year-old woman presented with a longstanding (40 years), subungual mass that deformed the nail of the left middle finger. Microscopic examination revealed a paucicellular tumor composed of hyperchromatic spindled, pleomorphic, floret-like giant cells embedded in haphazardly arranged collagen bundles in the dermis. No mitotic figures were seen. The tumor cells were vimentin-positive but did not stain with antibodies to S-100, cytokeratin, smooth muscle actin, factor XIIIa or CD34 negative. The diagnosis of a pleomorphic fibroma was made. Follow-up shows no evidence of tumor, 36 months after excision. CONCLUSION: Pleomorphic fibroma of the subungual region is an unusual cutaneous tumor with histologic features that may cause confusion with true sarcomas. This is only the second case reported of a subungual pleomorphic fibroma. Pleomorphic fibroma should be considered in the differential diagnosis of pleomorphic subungual tumors.     

Foamy cell angiosarcoma: a rare and deceptively bland variant of cutaneous angiosarcoma

Cutaneous angiosarcoma can sometimes mimic other benign and malignant lesions, thereby presenting a difficult differential diagnosis. In the two cases of cutaneous angiosarcoma presented herein, extensive foamy cell alteration of tumor cells resembled a reactive xanthogranulomatous process. Foamy cell angiosarcoma is an unusual and deceptively benign morphologic variant of cutaneous angiosarcoma. Critical features for diagnosis include the presence of a deep, permeative, sometimes ‘scaffolding’ growth pattern and subtle areas of vascular formation. Tatsas AD, Keedy VL, Florell SR, Simpson JF, Coffin CM, Kelley MC, Cates JMM. Foamy cell angiosarcoma: a rare and deceptively bland variant of cutaneous angiosarcoma.     

Benign fibrous histiocytoma of the eyelid with an unusual clinical presentation

Benign fibrous histiocytoma is a common soft tissue tumor that can be deep or superficially located. Although the deep type of fibrous histiocytoma has a predilection for the orbit, the eyelids are an unusual location for the cutaneous type. A 42-year-old woman had bilateral yellowish nodular masses of the eyelids for two years. Pathological examination after excision revealed benign fibrous histiocytoma. Our case is an unusual clinical presentation of cutaneous fibrous histiocytoma as well as a rare location such as the eyelids.     

Tumor of follicular infundibulum with unique features

Tumor of the follicular infundibulum is a rare benign cutaneous adnexal neoplasm with variable clinical presentation. In most cases the diagnosis is made with the help of histopathology, due to lack of a characteristic clinical presentation. The most common form is a solitary lesion, but it can be multiple or eruptive, then called infundibulomatose. This case report illustrates a patient with multiple lesions of tumor of the follicular infundibulum with bizarre aspect and atypical location.     

Two Clinically Unusual Cases of Folliculotropic Mycosis Fungoides: One with and the Other without Syringotropism

Mycosis fungoides is the most common form of cutaneous T-cell lymphoma, and it rarely exhibits predilection for hair follicle and eccrine gland infiltration. Here, we present 2 similar cases that display folliculotropism with varying amounts of follicular mucinosis, with and without syringotropism. The features observed in both cases were cystic, comedo-like, acneiform lesions; generalized involvement with loss of body hair; pruritus; and hidradenitis suppurativa-like lesions. Hypohidrosis as well as nail and palmoplantar involvement with lichen planopilaris-like clinical features were unique characteristics of the first case. Despite the well-known aggressive behavior of follicular mycosis fungoides, the presented cases had a subtle, slowly progressive, but persistent, clinical course. Folliculotropic and syringotropic mycosis fungoides are variants of cutaneous T-cell lymphoma. Clinical presentations might be challenging, and multiple, deep biopsy specimens containing adnexal structures are required for this critical diagnosis. Aggressive treatment may not be necessary in cases having an indolent course, especially in those with syringotropism.     

Lupus erythematosus tumidus with discoid lupus erythematosus-induced alopecia of the scalp

Lupus erythematosus tumidus (LET) is an uncommon variant of cutaneous lupus erythematosus. Lupus erythematodes tumidus is characterized by smooth, erythematous plaques on sun-exposed areas without surface changes, such as follicular plugs, atrophy, or scale. Histopathologic features include a lymphocytic, perivascular and periadnexal infiltrate with abundant interstitial, superficial, and deep dermal mucin without appreciable epidermal and vacuolar changes. Typically, LET is responsive to treatment with systemic antimalarials. We present a unique case of alopecia associated with LET, which was partially responsive to hydroxychloroquine. We also note that the plaque of LET is adjacent to the plaque of discoid lupus erythematosus.     

Unilesional follicular mycosis fungoides

Follicular mycosis fungoides (FMF) is an unusual clinical and histological variant of MF, characterized by selective involvement of hair follicles by atypical lymphocytes. We describe a female patient who had follicular papules located only on the medial aspect of her right thigh. To the best of our knowledge, this patient represents the first reported case of unilesional FMF.     

Androgen receptor expression helps to differentiate basal cell carcinoma from benign trichoblastic tumors

Histologic differentiation between basal cell carcinoma and benign trichoblastic neoplasms such as trichoepithelioma and trichoblastoma can be difficult on small biopsies. Therefore, several attempts have been made to identify immunohistochemical differences between these entities. Recent studies have shown androgen receptor expression in a number of mature epithelial structures in the skin and in epithelial neoplasms including basal cell carcinoma. In contrast, androgen receptor expression was absent in mature hair follicles or the few trichogenic neoplasms studied to date. These findings suggested that androgen receptor expression might be a useful adjunct in the histologic differential diagnosis between basal cell carcinoma and benign trichoblastic neoplasms. Therefore, we performed immunohistochemical analysis of androgen receptor expression in 32 basal cell carcinomas and 10 benign trichoblastic tumors (6 trichoepitheliomas and 4 trichoblastomas). In our study, at least focal expression of androgen receptor was detected in 78% of basal cell carcinomas. None of the trichoblastic tumors showed any androgen receptor immunoreactivity. These results confirm the lack of expression of androgen receptor in benign trichoblastic neoplasms and indicate that androgen receptor expression by tumor cells points to basal cell carcinoma as the most likely diagnosis.