Two cases of pilomatrix carcinoma

A systematic review of Pilomatrix carcinoma arising from the previous scar site of Pilomatrixoma

Pilomatrix carcinoma is a rare tumor arising from the hair follicle matrix cells most commonly seen in the head and neck region. Also known as "calcified epithelial carcinoma of Melherbe," it was first reported in 1980 by Lopansri and Mihm. Since then till date to the best of our knowledge only around 125 cases were reported in literature, of which only 11 cases were reported to arise from histologically proven areas of previous pilomatrixoma which is the benign variant. One such case is being reported here along with the review of literature. A 50-year-old man presented with a swelling in the nape of his neck since 6 months, which was gradually increasing in size. He had a history of similar swelling at the same site 18 months back for which he underwent a surgery at a center outside. Final histopathology report was suggestive of pilomatrixoma with negative margin. Wide local excision of the tumor with 3 cm margin, placement of surgical clips followed by a primary closure was done. The final histopathology report is suggestive of pilomatrix carcinoma. The patient has no recurrence in 6 months follow-up. The differential diagnosis of pilomatrix carcinoma should be considered in cases of recurrent skin tumors. Wide local excision is the preferred treatment. Re-excision should be done in margin positive cases and cases where simple excision was done due to improper preoperative diagnosis. Due to the rarity of the disease, adjuvant treatment is not properly defined.

Pilomatrix Carcinoma of the Antecubitum

We present the case of a 46-year-old male with atypically large left elbow pilomatrix carcinoma present for 10 years with emergent excision after developing life-threatening hemorrhage. Pilomatrix carcinoma is a dermal-based malignant tumor typically of the head and neck region. Histopathology shows islands of basaloid cells, shadow cells, and fibromyxoid fibroma. Reoccurrence is seen in 23% of cases on an average of six months after primary excision. The current standard of care is wide excision with close follow-up.

Pilomatrix carcinoma of the scalp with pulmonary metastasis: A case report of a complete response to oral endoxan and etoposide

Pilomatrix carcinoma is an extremely rare skin tumor derived from basaloid cells in the hair follicles; it often exhibits locally aggressive behavior with a tendency toward local recurrence. The average age of occurrence is 45 years, and there appears to be a male to female incidence ratio of 4:1. Although pilomatrix carcinomas are predominantly identified in the neck and scalp, there are studies in the literature reporting other tumor development sites, including the upper extremities, torso and popliteal fossa. If diagnosed at an early stage, this malignant tumor is generally treated with wide surgical resection. However, for the advanced-stage tumors, there are no standard treatment procedures known to produce good results. The current study presents the case of a 76-year-old male with pilomatrix carcinoma originating from the scalp with metastases to the lung. The patient had a rapid and complete clinical response following an oral combination chemotherapy regimen of cyclophosphamide and etoposide.

Pilomatrix carcinoma: 13 new cases and review of the literature with emphasis on predictors of metastasis

BACKGROUND

Pilomatrix carcinoma is a rare cutaneous tumor derived from follicular matrix cells with few cases documented in the literature.

OBJECTIVE

We sought to better characterize this tumor by analyzing its epidemiologic, clinical, and histopathologic features in 13 new cases and by reviewing the literature.

METHODS

All cases of pilomatrix carcinoma from a large regional dermatopathology practice were identified and analyzed by chart review for clinical and histopathologic characteristics. Similar characteristics were compiled from an additional 123 cases in the English-language literature. Cox proportional hazards regression models were used to determine risk factors associated with the development of metastasis for all identified metastatic tumors.

RESULTS

Our 13 tumors were most common in middle-aged to older white men and presented mostly on the head/neck. Histopathologically, tumors were asymmetric, were poorly circumscribed, were composed of basaloid and "ghost" cells, had frequent atypical mitoses, and had infrequent lymphovascular invasion. Wide excision was considered the most definitive treatment modality, but local recurrence was common. When analyzing all reported cases of metastasis using statistics, metastasis was significantly associated (hazard ratio 3.45, P < .0413) with local tumor recurrence.

LIMITATIONS

The retrospective, single-center design and the reliance on electronic medical records are limitations.

CONCLUSIONS

This study helps better characterize pilomatrix carcinoma and identifies potential predictors of metastasis.

Pilomatrix carcinomas contain mutations in CTNNB1, the gene encoding beta-catenin

Mutations in beta-catenin are present in benign pilomatrixomas. beta-catenin is a downstream effector in the WNT-signalling pathway, acting as a signal for differentiation and proliferation. Mutations in CTNNB1, the gene encoding beta-catenin, are present in a wide variety of benign and malignant neoplasms. We examined beta-catenin in a series of pilomatrix carcinomas (15 cases) by using immunohistochemistry and DNA sequencing of exon 3 from CTNNB1, and compared these to a series of benign pilomatrixomas (13 cases). All 11 pilomatrix carcinomas available for examination showed nuclear localization of beta-catenin and mutations in exon 3 similar to those demonstrated in benign pilomatrixomas. Two of 11 pilomatrix carcinomas showed significant nuclear accumulation of p53, whereas this was absent in all 13 benign pilomatrixomas. Expression of nuclear cyclin D1 was similar in both benign pilomatrixomas and pilomatrix carcinomas. Clinical follow-up from the 15 malignant cases reported in this study and by others indicates that wide excision offers superior control of local recurrence, compared to simple excision. Immunohistochemical and molecular analysis of beta-catenin reveals that both pilomatrix carcinomas and benign pilomatrixomas harbour mutations in beta-catenin. This implies a common initial pathogenesis and is compatible with the proposition that pilomatrix carcinomas may at least on occasion arise from their benign counterparts.

Pilomatrix carcinoma with lymph node and pulmonary metastasis: report of a case arising on the knee

A 58-year-old woman presented with a pilomatrix carcinoma on the right knee. The tumor developed at the site of a previous lesion that had been present since she was 30 years old. Histologic study showed the presence of basaloid cells with numerous atypical mitoses, shadow cells, and calcification. After several surgical excisions, the tumor mass infiltrated the subcutaneous tissue, muscle, and bone, resulting in inguinal lymph node and pulmonary metastasis. We also review the literature and comment on the histopathologic differences from other cutaneous tumors.

Pilomatrix carcinoma: a clinicopathologic study of six cases and review of the literature

Pilomatrix carcinoma, the malignant variant of pilomatrixoma, is a rare entity. The authors report on six patients with pilomatrix carcinoma and review the pertinent literature. The lesions showed a predilection for elderly individuals (mean age, 61 years) with a male:female ratio of 5:1, and they presented as dermal or subcutaneous tumors located on the head and neck (5 neoplasms) and chest (1 neoplasm). Tumors varied in size from 0.6 cm to 2.5 cm (mean, 1.78 cm). None of the lesions recurred after wide local excision. On scanning magnification, all tumors showed the architectural features of a malignant neoplasm (asymmetry and poor circumscription, presence of several markedly sized and variably shaped basaloid aggregations, and ulceration). The tumors were composed of pleomorphic basaloid cells with prominent nucleoli and frequent atypical mitoses accompanied by central areas with keratotic material, shadow cells, and foci of necrosis. The tumor nests were surrounded by a desmoplastic stroma and infiltrated the adjacent tissues. Vascular or perineural infiltration was not observed. In one case, the basaloid cells contained abundant melanin pigment in their cytoplasms. Pilomatrix carcinoma is a neoplasm of low-grade malignancy that should be distinguished from the conventional pilomatrixoma and its variants (aggressive pilomatrixoma and proliferating pilomatrixoma), matricoma, and basal cell carcinoma with matrical differentiation. Clinicians and pathologists should be aware of the occurrence of pilomatrix carcinoma because of its potential for distant metastases.

Pilomatrix carcinoma: a report of a case arising from a previously excised pilomatrixoma and a review of the literature

A 63-year-old woman was evaluated in 1995 for a nodule on the left parietal scalp. Biopsy revealed pilomatrixoma. The lesion was treated by curettage. The patient returned to the clinic in March of 1998 with a 2-month history of a rapidly growing nodule at the surgical site. Histology showed changes consistent with pilomatrix carcinoma. We will discuss the malignant transformation of a common hair matrix tumor and review the literature.

Melanocytic matricoma: a report of two cases of a new entity

Many reports exist of pigmented adnexal tumors containing dendritic melanocytes such as pigmented basal cell carcinomas and pigmented pilomatricomas. Correspondingly, melanocytes are a known component of the bulbs of anagen follicles. The phenomenon of melanization of adnexal tumors highlights the interrelationship between melanocytes and adnexal epithelium and may represent normal melanocytes colonizing a neoplastic proliferation. We report on two cases of a unique tumor composed of neoplastic matrical cells with a significant component of melanocytes. Both cases presented as pigmented papules in older men (66 and 80 years, forearm and pectoral region, respectively). Histologically, these were well-defined nodular proliferations composed of variably melanized, pleomorphic, and mitotically active matrical and supramatrical cells forming clusters of "shadow cells." Admixed with the epithelial cells were numerous melanized dendritic melanocytes. Shadow cells expressed keratin 13, and a subpopulation of S-100 protein-positive dendritic cells were evident. No recurrence of any type was found after reexcisions 4 months and 2 years later. We propose the name of melanocytic matricoma for these two heretofore unreported cases of a unique neoplasm composed of matrical cells and melanocytes recapitulating epithelial-melanocyte interaction in the follicular anagen bulb. Although their small size, circumscription and clinical course suggest a benign nature, melanocytic matricomas' cytologic atypia disclose the potential for malignant behavior.

Pilomatrix carcinoma with multiple metastases: report of a case and review of the literature

Pilomatrix carcinoma, the malignant counterpart of pilomatrixoma, is rare, with only 55 cases reported, and only four cases with visceral metastases described in the literature. Here we present a case report and a literature review on this rare tumour. A 74-year-old male with a pilomatrix carcinoma from the left temporal region presented in July 1996 and the tumour was excised. One month after diagnosis, metastases to both lungs and to a regional lymph node were found and histologically verified. The patient also developed metastases in the abdomen, back and thoracic spine. The latter resulted in spinal cord compression and paraplegia. Despite systemic chemotherapy with intravenous cisplatin and 5-fluorouracil and localised radiotherapy to the thoracic spine, progression and deterioration led to death within 3 months from time of diagnosis. Pilomatrix carcinomas are usually indolent. In our patient, however, the malignant disease progressed rapidly and it appeared to be resistant to both chemotherapy and irradiation.

Malignant pilomatrixoma of the scalp

A 33 yr old man with a history of pilomatrixoma of the scalp, presented 5 mths later with a metastatic undifferentiated carcinoma in a submandibular lymph node. The cutaneous and lymph node tumors showed close histological similarity and features of malignancy. Investigations over 30 mths excluded a primary neoplasm elsewhere and consequently led to the diagnosis of malignant pilomatrixoma. These tumors are rare and most often located on the scalp. Most of the affected patients are middle age males. Wide excision is advised to avoid recurrences.

Pilary complex carcinoma: an adnexal carcinoma of the skin with differentiation towards the components of the pilary complex

We report twelve cases with a distinctive form of adnexal carcinoma occurring most commonly over the head and neck of relatively old individuals. The growth was single in all cases, deep dermal in location, and consisted of massive proliferation of small basaloid cells with only occasional connection with the surface epidermis. The basaloid tumor masses showed only a few areas of palisading of their outer cell nuclei and occasional retraction space formation. The neoplasm revealed scattered areas of trichilemmal and epidermoid keratinization, foci of sebaceous, and areas of sweat ductal differentiation indicating participation of various components of the pilary complex.

Pilomatrix carcinoma

BACKGROUND

Pilomatrix carcinoma, a malignant variant of pilomatrixoma, is extremely rare. The authors report 20 patients with pilomatrix carcinoma and review the pertinent literature.

METHODS

Tumors showing histologic features of pilomatrix carcinoma were selected from the files of the Armed Forces Institute of Pathology. Clinical data of the 20 selected patients were reviewed, and follow-up information was obtained. Sections stained with hematoxylin and eosin were studied in all patients. Special stains were used in selected patients.

RESULTS

Pilomatrix carcinomas were asymptomatic dermal and subcutaneous masses with a predilection for the posterior neck and back. Tumors varied in size, from 1-10 cm (mean, 4.6 cm), and occurred more often in middle-age men, with a male:female ratio of 4:1 (mean age, 45 years). Histologically, pilomatrix carcinomas are characterized by sheets and islands of proliferating atypical basaloid cells with an infiltrating border. Transition to squamous cells, clear cells, areas of necrosis and mitoses often are seen. Keratinization with formation of keratin cysts, shadow cells, and trichohyalin and keratohyalin granules are found in all tumors, in conjunction with calcification and foreign body giant cell reaction, just as are seen in benign pilomatrixoma. Follow-up of 17 patients revealed local recurrence in 10 (59%), with multiple recurrences in 3. One patient had pulmonary metastasis, and one died of extensive local spread of the tumor.

CONCLUSION

Pilomatrix carcinomas are locally aggressive tumors that have a tendency to recur, especially when they are incompletely excised. Greater anaplasia and deep soft tissue infiltration were associated with a higher incidence of recurrence and death. Wide excision is the preferred treatment. The role of radiation therapy is unclear.