Pilomatrix Carcinoma: A Benign-Mimic with Malignant Consequences - A Case Report and Review of the Current Literature.

Introduction: Pilomatrix carcinomas (PMXCs) are uncommon, locally aggressive tumors with high recurrence rates, metastatic potential, and fewer than 130 cases reported in the literature. Typically, they present as an unassuming, firm, dermal swelling and therefore are frequently mistaken for more common, benign masses, leading to undertreatment which can cause local invasion and metastatic spread. Diagnosis relies on excision with pathologic analysis; however once diagnosed, there are no current recommendations to guide treatment or surveillance for recurrence or metastases. Case Presentation: Here, we present a case of one of these rare tumors. Our case describes a 1.5 × 2.5 cm firm, mobile mass at the supraorbital rim in an otherwise healthy, young patient. Prior to removal, we suspected a benign pathology; however, excision proved difficult and pathologic diagnosis was consistent with PMXC. Following discussion with tumor board, decision was made to perform Mohs micrographic surgery and staging via CT scans with regular follow-up and surveillance scans. Conclusion: PMXCs are exceedingly rare diagnoses and present like many benign lesions. Therefore, we elected to document this case to encourage providers to keep these biologically aggressive tumors on their list of differential diagnoses in an unsuspecting mass, as well as to provide our own recommendations for treatment and screening for recurrence and metastatic spread.

The Rarity in the Rarity: Presentation of Three Cases of Cutaneous Carcinosarcoma with Clinical and Histopathological Insights.

A cutaneous carcinosarcoma (cCS) is a rare and aggressive skin cancer characterized by both carcinomatous (epithelial) and sarcomatous (mesenchymal) components, making it a biphasic tumor. Despite its occurrence in various organs, a cCS is exceptionally rare in the skin, predominantly affecting older males. The etiology of a cCS is unclear, but it may originate from a single progenitor cell capable of dual differentiation or from a collision of carcinoma and sarcoma cells. Clinically, a cCS presents as a rapidly growing, painful, ulcerated nodule or plaque on sun-exposed skin, with a high risk of local invasion and metastasis. Histopathologically, a cCS includes various epithelial components, such as squamous cell carcinoma and basal cell carcinoma, along with undifferentiated sarcomatous components resembling atypical fibroxanthoma. The tumor may also exhibit heterologous differentiation like angiosarcomatous or rhabdomyosarcomatous features. We present three cases of a cCS, highlighting their clinical and histological characteristics and comparing them with previously reported cases. Understanding a cCS is complicated by its rarity and diverse presentation, emphasizing the need for further research to elucidate its pathogenesis and optimal management.

Case report: Pilomatrix carcinoma with PDL1 expression and CDKN2A aberrant.

Case report: A 55-year-old male patient developed a mass in the left inguinal area with left lower limb swelling and first visited a local hospital 3 months earlier because of unrelieved pain. An MRI scan suggested left suprapubic branch and left acetabular bone destruction, abnormal soft tissue signals within the iliopsoas muscle of the anterior edge of the left iliac bone, and enlarged lymph nodes in the left iliac fossa and left inguinal region. The patient subsequently underwent left pelvic lesion open biopsy and inguinal lymph node resection biopsy. According to pathological reports, the left inguinal mass was considered to be a malignant tumor of cutaneous accessory origin (pilomatrix carcinoma) with extensive vitreous changes. The suprapupubis branch mass was considered to be a bone metastatic pilomatrix carcinoma. Immunohistochemistry (IHC) revealed a PDL1 combined positive score (CPS) of 8. DNA next-generation sequencing (NGS) showed CDKN2A L65Rfs*53 mutation. The patient received three cycles of gemcitabine and nedaplatin. However, the lesion progressed. Conclusion: Chemotherapy is not effective for treating pilomatrix carcinoma. PDL1 antibodies and CDK4/6 inhibitors might be treatment options for pilomatrix carcinoma.

Pilomatrix carcinoma of the lower extremity: A rare case report and literature review.

INTRODUCTION: Pilomatrix carcinoma (PC) is a rare skin malignancy of the hair follicles matrix that tends to be locally aggressive with 10-16 % risk of metastasis mostly to the pulmonary and lymphatic system. There are no clear protocols for the management of PCs, however surgical intervention with clear margins has been highly considered in PC management to decrease risk of recurrence. CASE PRESENTATION: A 40 year-old male patient presented to our clinic to evaluate an asymptomatic, slow-growing nodule localized on his left thigh. A CT scan revealed a well-defined, enhanced lesion with microcalcification. "En bloc" surgical resection of the lesion was performed and histopathology confirmed the diagnosis of pilomatrix carcinoma. CLINICAL DISCUSSION: Given its rarity, there are no definitive guidelines regarding PC treatment. However, surgical intervention with clear margins including wide local excision or Mohs micrographic surgery has been highly considered. In our case, wide excision of the lesion with clear margins was performed with no evidence of recurrence one year later. CONCLUSION: Given the local aggressive nature of PC, appropriate surgical intervention is essential in decreasing the risk of recurrence. Wide excision with clear margins has been proposed to decrease the risk of recurrence. Additionally, total-body skin examination should be done 2-3 times annually to evaluate for recurrence or metastasis.

Giant pilomatrix carcinoma of the scalp with intracranial extension: A case report.

Key Clinical Message: A very rare skin cancer. Malignant variant of pilomatricoma. It is unique because of its highly aggressive behavior. Responds poorly to chemotherapy and radiotherapy. Treated with a wide surgical excision with safe margins. Abstract: Pilomatrix carcinoma is uncommon and locally aggressive tumor of the hair follicle matrix. It is a malignant variant of pilomatricoma. If left untreated for a long time may attain massive size and has the potential for distant spread. Only few cases with brain extension have been reported in the literature. Diagnosis of these tumors is established by histopathology. Although pilomatrixoma and pilomatrix carcinoma are well-recognized lesions, clinically they are frequently misdiagnosed as other skin conditions. The tumors respond poorly to chemotherapy and radiotherapy. Thus, recommended treatment is a wide surgical excision with safe margins. Herein, we report the case of a 39-year-old African woman with pilomatrix carcinoma of the scalp eroding the skull bone with intracranial extension.

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-Rare Presentation of an Unusual Cutaneous Malignancy.

INTRODUCTION OR BACKGROUND: Pilomatrix carcinoma is a rare malignant neoplasm arising from the root of hair follicles, with only 150 cases described in the world literature. It is most commonly seen in the head and neck region. CASE PRESENTATION: We describe a case of malignant pilomatrix carcinoma in a 62-year-old gentleman presenting as a solitary globular mass over the right anterior chest wall along with a brief review of literature. DISCUSSION AND CONCLUSION: Surgical excision with a wide margin is the current standard of care for chest wall pilomatrix carcinoma and is associated with the least recurrence. Role of radiation as definitive treatment of the primary or as adjuvant therapy has not been clearly established.

Pilomatrix Carcinoma In A 4-Year-Old Child With An Unusual Presentation.

Pilomatrix carcinoma is a rare, locally aggressive variant of pilomatrixoma with a high rate of recurrence and risk of distant metastasis. We report an unusual presentation of a pilomatrix carcinoma in a 4-year-old male child who presented with recurrent lesions on his left cheek. At the age of 1 month of life, he presented with a soft tissue swelling on his left cheek. The lesion showed a circumscribed proliferation of basaloid cells with central areas of eosinophilic ghost shadow cells and intermediate cells. Basaloid nests showed round to oval, hyperchromatic nuclei with open nuclear chromatin, prominent nucleoli and frequent mitoses but no marked nuclear pleomorphism or infiltration was identified. The lesion recurred twice at the same site. Both recurrences showed similar morphology as the primary tumour however there were extensive areas of stromal necrosis, infiltrating edges, frequent mitoses with atypical forms, and lymphovascular invasion. There was no marked nuclear pleomorphism. Morphological features favoured a diagnosis of pilomatrix carcinoma. The child is still on follow-up and no recurrence has been identified to date. Pilomatric carcinoma is rarely reported in infants. Due to its rarity, aggressive histological features may be missed.

Pilomatrix-like High-Grade Endometrioid Carcinoma of the Ovary: Case Report, Literature Review, and Differential Diagnosis.

Pilomatrix-like high-grade endometrioid carcinoma (PiMHEC) has recently been described as an aggressive variant of endometrial carcinoma. Herein, we described a case of ovarian PiMHEC, comparing it to endometrial PiMHEC and assessing previously published cases of putative ovarian PiMHEC. A 65-year-old woman underwent hysterectomy for an ovarian tumor characterized by solid nests of basaloid cells with prominent ghost cell keratinization. Immunohistochemistry showed nuclear ß-catenin and CDX2 expression and loss of estrogen and progesterone receptors and PAX8. These features were consistently observed in all previously published cases and may represent diagnostic criteria of PiMHEC. Other frequent features were geographic necrosis and a low-grade endometrioid component. CK7, neuroendocrine, and basal/squamous markers were inconsistently expressed. All cases with available follow-up showed poor prognosis. PiMHEC should be distinguished from mimickers, such as high-grade endometrioid carcinoma with geographic necrosis, low-grade endometrioid carcinoma with ghost cell keratinization, and undifferentiated/dedifferentiated carcinoma. In conclusion, PiMHEC can also occur in the ovary and shows several consistent clinical, morphological, and immunophenotypical features. These features support that PiMHEC is a distinct entity requiring an aggressive management.

Malignant Pilomatricoma of the Lower Extremity: A Difficult and Rare Diagnosis.

Malignant pilomatricoma is a rare cutaneous malignancy that is commonly found on the head and neck. We present a patient with malignant pilomatricoma of the lower extremity with intralesional calcification and giant cells, confirmed by histopathology. This patient's case represents a clinically important variation of malignant pilomatricoma in an uncommon anatomical location.

CDX2 and SATB2 positivity in pilomatrix carcinoma: Avoiding an erroneous diagnosis of cutaneous metastasis of gastrointestinal origin.

An 80-year-old female presented with a slowly growing 2-cm nodule on her shoulder over a 1-year period. Histopathologic sections of a biopsy specimen showed a multinodular, dermal-based basaloid tumor with areas of clear-cell change, stromal induction, as well as significant cytologic atypia and atypical mitotic activity. An initial investigation revealed positive staining of CDX2, a well-known marker of tumors of gastrointestinal origin. The case was referred to our dermatopathology service for consultation to determine if the lesion was in keeping with a cutaneous metastasis. On receipt of the case, an extended immunohistochemical panel was performed including SATB2, which displayed a similar pattern of staining as seen with CDX2. Although pathologists are most familiar with CDX2 and SATB2 as markers of gastrointestinal origin, the recent dermatopathology literature highlights that primary adnexal lesions of the skin also display positivity for CDX2 and can exhibit SATB2 positivity. We share a case of pilomatrix carcinoma with positive expression of nuclear CDX2 and SATB2, adding to the recent literature to (a) increase recognition of this staining pattern in hair follicle tumors, and (b) discuss briefly the shared molecular underpinnings in the tumorigenesis of gastrointestinal tumors and tumors of hair follicle origin that help clarify this underrecognized immunohistochemical pattern.

Pilomatrixoma with Atypical Features: A Case Report.

Pilomatrixoma is an uncommon, benign tumor with differentiation towards both the hair matrix and cells arising in the cortex, most frequently appearing in the first or second decade of life. In rare instances, pilomatrixomas can show malignant transformation. Pilomatrix carcinoma is extremely uncommon and has traditionally been considered a tumor of low malignant potential; however, a high local recurrence rate has been reported. There is a paucity of literature on these lesions, with only a few reports describing the spectrum of malignant changes seen in these lesions. In this case report, we present a case of pilomatrixoma in an adult patient showing atypical features. While the tumor is small, there are focal features that suggest progression to malignancy, but do not fulfill the criteria for pilomatrix carcinoma. These focal atypical features include a focal infiltrative pattern at the periphery, with a variable cytological atypia and an increased mitotic rate, up to five mitotic events/high-power field. Irregular foci of central necrosis (comedonecrosis) were present in several lobules. Some of the features identified were similar to a subset of pilomatrixoma, known as "proliferating pilomatrixoma." However, our case did not have the diffuse changes or larger size that has been frequently reported in "proliferating pilomatrixoma." In conclusion, given the lack of focality of the changes, the lesion in our case is best described as a pilomatricoma with atypical features. Furthermore, our case may highlight the need to ensure close clinical follow-up for these lesions with unexpected atypical features that raise concern of recurrence and malignant transformation.

Pilomatrix carcinoma of the male breast: a case report.

Pilomatrix carcinoma (PC) is a rare skin adnexal neoplasm derived from piliferous follicles, usually occurring in the head and neck region. An optimal treatment for PC has not yet been established, while surgery with wide margins is recommended, with radiation therapy (RT) and chemotherapy improving the curative effect. Location of this tumor in the breast is exceedingly rare, especially for a male. We now report an unusual case of a 53-year-old male who presented with 2 palpable masses in the right breast, which had been removed surgically about 4 and a half years prior, but recurred after 7 months. Ultrasonography revealed 2 irregular low-echo masses with a well-defined boundary, and computed tomography (CT) showed 2 soft tissue masses in subcutaneous tissue of the right breast. The tumors were completely removed without RT and chemotherapy. After about 4 years' follow-up, the patient remains free of local recurrence and metastasis. To the best of our knowledge, only 2 cases of PC in the breast region have been reported, but were female.

Not Your Average Skin Cancer: A Rare Case of Pilomatrix Carcinoma.

Pilomatrix carcinoma is a rare malignancy stemming from aberrant proliferation of matrical cells found in developing hair. This neoplasm demonstrates a bimodal age distribution and a proclivity for developing on the head or neck. Clinically, a firm, painless, violaceous nodule with overlying ulceration is commonly described. Pilomatrix carcinoma is considered a variable-grade malignancy that tends to be locally aggressive, though metastatic disease occurs in 10 to 16 percent of cases. Mortality rates range from 7 to 9 percent. Although there is no definitive treatment protocol, surgical intervention in the form of local excision or via Mohs micrographic surgery can be considered, with radiotherapy adopted as an effective alternative for nonsurgical, recurrent, or metastatic disease. Here, we describe the case of a 62-year-old man who presented for evaluation of a red, enlarging lesion on his forehead which became tender and started to bleed shortly before the patient presented to our clinic. The patient was ultimately referred to a tertiary care center for surgical excision and, at the time of this pubilcation, has been tumor-free for more than one year. This case of a rare and often unconsidered neoplasm underscores the importance of clinical suspicion and close patient follow up to prevent local recurrence, metastasis, and death.

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 right postauricular region: A case report and literature review.

INTRODUCTION: Pilomatrix carcinoma is a rare aggressive tumor with a high rate of local recurrence after surgical excision. Diagnosis is made by histopathology and when discovered, wide local excision has been shown to have the best results. PRESENTATION OF CASE: We report a case of a 74-year-old male incidentally found to have a large right postauricular mass and regional lymphadenopathy. The mass was biopsied and proven to be a malignant pilomatrixoma. Wide local excision and level II and III neck dissection with reconstruction using a right supraclavicular flap was performed. DISCUSSION: Pilomatrix carcinoma is a lesion first described in 1880 by Malherbe and Chenantais. It is unknown if these tumors arise de novo or arise through malignant transformation of a benign pilomatrixoma. There are similarities between the benign lesion and its malignant counterpart in terms of activating mutations in signaling pathways. A well-defined gold standard for surgical management has not been established, but currently wide local excision with safe margins is recommended along with regional lymph node dissection when metastasis is suspected. Currently, no chemotherapy regimen has been shown to be effective in local control or in preventing metastatic spread. CONCLUSION: Pilomatrix carcinoma, given its aggressive nature, has a high propensity for recurrence after excision. It is important to perform wide local excision to avoid an incomplete resection and higher recurrence rates. Further studies will be needed to create a more defined standard of treatment and to evaluate the role of adjuvant chemotherapy and radiation therapy.

Sarcomatoid pilomatrix carcinoma.

Pilomatrix (pilomatrical) carcinoma is a rare cutaneous adnexal tumor with matrical differentiation and recurrent and metastatic potential. Sarcomatoid pilomatrix carcinoma is a rare variant which shows a sarcomatoid component intermingling with the epithelial one. There are only 4 cases previously published. We present an additional case on the hand of a 78 year-old man which appeared as a 6 mm hyperkeratotic, focally ulcerated plaque. A shave biopsy demonstrated a dermal infiltrative neoplasm, composed of markedly atypical-appearing basaloid cells with focal necrotic/ghost cells, as well as an intimately associated population of atypical oval to spindle-shaped cells. Both the epithelial and the sarcomatoid components expressed cytokeratins (CKs) AE1/AE3, CK 5/6 and CAM 5.2, as well as beta-catenin and LEF-1. The tumor failed to express CK7, CK20, S100, thyroid transcription factor 1 (TTF1), CDX2, prostate-specific antigen (PSA) and CD34. The tumor was completely excised with Mohs surgery, and there has been no recurrence in the 8 months of follow-up to date.