Differentiation and risk stratification of basal cell carcinoma with deep learning on histopathologic images and measuring nuclei and tumor microenvironment features.

BACKGROUND: Nuclear pleomorphism and tumor microenvironment (TME) play a critical role in cancer development and progression. Identifying most predictive nuclei and TME features of basal cell carcinoma (BCC) may provide insights into which characteristics pathologists can use to distinguish and stratify this entity. OBJECTIVES: To develop an automated workflow based on nuclei and TME features from basaloid cell tumor regions to differentiate BCC from trichoepithelioma (TE) and stratify BCC into high-risk (HR) and low-risk (LR) subtypes, and to identify the nuclear and TME characteristics profile of different basaloid cell tumors. METHODS: The deep learning systems were trained on 161 H&E -stained sections which contained 51 sections of HR-BCC, 50 sections of LR-BCC and 60 sections of TE from one institution (D1), and externally and independently validated on D2 (46 sections) and D3 (76 sections), from 2015 to 2022. 60%, 20% and 20% of D1 data were randomly splitted for training, validation and testing, respectively. The framework comprised four stages: tumor regions identification by multi-head self-attention (MSA) U-Net, nuclei segmentation by HoVer-Net, quantitative feature by handcrafted extraction, and differentiation and risk stratification classifier construction. Pixel accuracy, precision, recall, dice score, intersection over union (IoU) and area under the curve (AUC) were used to evaluate the performance of tumor segmentation model and classifiers. RESULTS: MSA-U-Net model detected tumor regions with 0.910 precision, 0.869 recall, 0.889 dice score and 0.800 IoU. The differentiation classifier achieved 0.977 ± 0.0159, 0.955 ± 0.0181, 0.885 ± 0.0237 AUC in D1, D2 and D3, respectively. The most discriminative features between BCC and TE contained Homogeneity, Elongation, T-T_meanEdgeLength, T-T_Nsubgraph, S-T_HarmonicCentrality, S-S_Degrees. The risk stratification model can well predict HR-BCC and LR-BCC with 0.920 ± 0.0579, 0.839 ± 0.0176, 0.825 ± 0.0153 AUC in D1, D2 and D3, respectively. The most discriminative features between HR-BCC and LR-BCC comprised IntensityMin, Solidity, T-T_minEdgeLength, T-T_Coreness, T-T_Degrees, T-T_Betweenness, S-T_Degrees. CONCLUSIONS: This framework hold potential for future use as a second opinion helping inform diagnosis of BCC, and identify nuclei and TME features related with malignancy and tumor risk stratification.

Brooke-Spiegler syndrome: radiotherapy as the last resort?

PURPOSE: To describe the case of successful radiotherapeutic treatment of a woman suffering from Brooke-Spiegler syndrome who had multiple disfiguring cylindromas on the entire scalp and further tumors on the trunk. METHODS: After decades of treatment with conventional therapies including surgery and topically applied salicylic acid, the 73-year-old woman agreed to undergo radiotherapeutic treatment. She received 60 Gy to the scalp and 36 Gy to painful nodules in the lumbar spine region. RESULTS: Over a follow-up period of 14 and 11 years, respectively, the scalp nodules almost completely regressed, while the lumbar nodules became painless and considerably smaller. Apart from alopecia, no late adverse effects of treatment remain. CONCLUSION: This case should remind us of the potential role that radiotherapy could play in treating Brooke-Spiegler syndrome. The required dose for treatment of such extensive disease is still a matter of debate due to the scarcity of radiotherapeutic experience. This case demonstrates that for scalp tumors, 30â€¯× 2 Gy can result in long-term tumor control, while other dose prescriptions may be adequate for tumors in other locations.

Morphologically high-grade trichoblastic carcinoma: a clinicopathological study with long-term clinical follow-up.

AIMS: Trichoblastic carcinomas (malignant trichoblastomas) are rare and poorly documented neoplasms characterised by malignant transformation of a pre-existing benign trichoblastoma, and are subdivided histologically into low-grade and high-grade tumours. Whereas morphologically low-grade trichoblastic carcinomas show indolent behaviour, morphologically high-grade trichoblastic carcinomas have been associated with a poor prognosis, but little is known about their true biological potential. The aim of this study was to better define the clinicopathological features and outcomes of morphologically high-grade trichoblastic carcinomas. METHODS AND RESULTS: Four high-grade trichoblastic carcinomas were retrieved from departmental files, and the clinical and histopathological features and follow-up were recorded. The tumours presented as nodules on the scalps, necks and shoulders of adults (median age, 40 years; range, 30-55 years) with a female predominance of 3:1. Three patients had a longstanding history with recent change. Histologically, three tumours were characterised by an expansile cellular nodule composed of sheets of pleomorphic epithelioid cells with brisk mitotic activity and necrosis arising in a background of a benign trichoblastoma. One tumour showed a more gradual transition from a benign trichoepithelioma to an undifferentiated carcinoma with infiltrative growth and perineural infiltration. All patients were alive with no evidence of recurrence or metastasis following complete excision after a median follow-up of 96 months (range, 30-180 months). CONCLUSIONS: The correct diagnosis of high-grade trichoblastic carcinoma relies on adequate sampling and recognition of the benign trichoblastic precursor lesion, i.e. trichoblastoma or trichoepithelioma. Despite the concerning histological features of the malignant component, the tumours appear to be less aggressive than previously thought.

Management of multiple trichoepithelioma: A review of pharmacological therapies.

Trichoepithelioma is a rare benign adnexal neoplasm that can occur in various forms including solitary, multiple, familial or nonfamilial. Multiple facial trichoepithelioma can be associated with significant psychosocial burden. Conventional treatment modalities such as surgical excision and ablative laser have variable results and can be associated with unacceptable complications and tumour regrowth. Pharmacological interventions such as topical and systemic agents are potentially effective but clinical data are limited and treatments are poorly standardised. We review the available evidence to determine the role of pharmacological therapies in the management of multiple trichoepithelioma. Demographic and clinical data were retrospectively collected from the available English literature. Majority of cases treated with pharmacological therapies (93.75%) had a positive treatment outcome, achieving partial lesion response. Adverse effects associated with pharmacological therapies were generally well tolerated and did not interrupt treatment. There are limitations as to how our results can be interpreted owing to the paucity of good quality evidence, spectrum of disease severity, and diversity of study designs utilised in the included articles. Nonetheless, the results of our study indicate that while most pharmacological interventions for multiple trichoepithelioma produce a partial response, they can be employed as effective suppressive therapies, either alone or in conjunction with conventional treatments. The current evidence for pharmacological therapies remains largely anecdotal justifying the need for further clinical studies in this area.

The E3 ubiquitin ligase MIB2 enhances inflammation by degrading the deubiquitinating enzyme CYLD.

The tumor suppressor CYLD is a deubiquitinating enzyme that suppresses polyubiquitin-dependent signaling pathways, including the proinflammatory and cell growth-promoting NF-κB pathway. Missense mutations in the CYLD gene are present in individuals with syndromes such as multiple familial trichoepithelioma (MFT), but the pathogenic roles of these mutations remain unclear. Recent studies have shown that CYLD interacts with a RING finger domain protein, mind bomb homologue 2 (MIB2), in the regulation of NOTCH signaling. However, whether MIB2 is an E3 ubiquitin ligase that acts on CYLD is unknown. Here, using the cell-free-based AlphaScreen and pulldown assays to detect protein-protein interactions, along with immunofluorescence assays and murine Mib2 knockout cells and animals, we demonstrate that MIB2 promotes proteasomal degradation of CYLD and enhances NF-κB signaling. Of note, arthritic inflammation was suppressed in Mib2-deficient mice. We further observed that the ankyrin repeat in MIB2 interacts with the third CAP domain in CYLD and that MIB2 catalyzes Lys-48-linked polyubiquitination of CYLD at Lys-338 and Lys-530. MIB2-dependent CYLD degradation activated NF-κB signaling via tumor necrosis factor alpha (TNFα) stimulation and the linear ubiquitination assembly complex (LUBAC). Mib2-knockout mice had reduced serum interleukin-6 (IL-6) and exhibited suppressed inflammatory responses in the K/BxN serum-transfer arthritis model. Interestingly, MIB2 significantly enhanced the degradation of a CYLDP904L variant identified in an individual with MFT, although the molecular pathogenesis of the disease was not clarified here. Together, these results suggest that MIB2 enhances NF-κB signaling in inflammation by promoting the ubiquitin-dependent degradation of CYLD.

Ln-γ 2 chain of laminin-332 is a useful marker in differentiating between benign and malignant sclerosing adnexal neoplasms.

AIMS: Laminin (Ln)-γ 2, one of the chains of Ln-332, is a marker of invasive tumours and is frequently expressed as a monomer in malignant tumours. Desmoplastic trichoepithelioma (DTE), some types of basal cell carcinoma (BCC) (infiltrating and morphoeic BCC) and microcystic adnexal carcinoma (MAC) belong to a group of tumours known as sclerosing adnexal neoplasms (SAN) that are frequently difficult to differentiate and often require immunohistochemistry for diagnosis. The aim of this study was to assess the usefulness of Ln-γ 2 expression in the differential diagnosis of DTE, infiltrating/morphoeic BCC, MAC and syringoma. METHODS AND RESULTS: In this study, we compared the expression of Ln-γ 2 in infiltrating/morphoeic BCC (n = 28), DTE (n = 26), MAC (n = 10) and syringoma (n = 20). Immunohistochemically, Ln-γ 2 positivity was noted in 96% (27 cases) of infiltrating/morphoeic BCC and 90% (nine cases) of MAC, while all DTE and syringoma cases were negative. Furthermore, Ln-γ 2 expression pattern in infiltrating/morphoeic BCC was different from that in MAC. Ln-γ 2 expression was found in the cytoplasm of tumour cells in infiltrating/morphoeic BCC tumour cells, while in MAC linear expression was noted both along tumour nests and in the cytoplasm. CONCLUSION: Ln-γ 2 is a helpful adjunct in the differential diagnosis of SAN.

Are clinicians successful in diagnosing cutaneous adnexal tumors? a retrospective, clinicopathological study

Background/aim: Cutaneous adnexal tumors (CAT) are rare tumors originating from the adnexal epithelial parts of the skin. Due to its clinical and histopathological characteristics comparable with other diseases, clinicians and pathologists experience difficulties in its diagnosis.We aimed to reveal the clinical and histopathological characteristics of the retrospectively screened cases and to compare the prediagnoses and histopathological diagnoses of clinicians. Materials and methods: The data of the last 5 years were scanned and patients with histopathological diagnosis of CAT were included in the study. Results: A total of 65 patients, including 39 female and 26 male patients aged between 8 and 88, were included in the study. The female to male ratio was 1.5, and the mean age of the patients was 46.15 ± 21.8 years. The benign tumor rate was 95.4%, whereas the malignant tumor rate was 4.6%. 38.5% of the tumors were presenting sebaceous, 35.4% of them were presenting follicular, and 18.5% of them were presenting eccrine differentiation. It was most commonly seen in the head-neck region with a rate of 66.1%. When clinical and histopathological prediagnoses were compared, prediagnoses and histopathological diagnoses were compatible in 45% of the cases. Most frequently, it was the basal cell carcinoma, epidermal cyst, and sebaceous hyperplasia identified in preliminary diagnoses. Conclusion: Cutaneous adnexal tumors are very important, as they can accompany different syndromes and may be malignant. Due to difficulties in its clinical diagnosis, histopathological examination must be performed from suspicious lesions for definitive diagnosis.

Diagnostic accuracy of immunohistochemical markers in differentiation between basal cell carcinoma and trichoepithelioma in small biopsy specimens.

BACKGROUND: The distinction of trichoepithelioma from basal cell carcinoma in small superficial biopsies is important but often challenging. This has inspired many scientists to test the validity of immunohistochemical markers in the differential diagnosis. OBJECTIVES: To develop an immunohistochemical protocol that helps in differentiation between both trichoepithelioma (TE) and basal cell carcinoma (BCC) with higher sensitivity and specificity. METHODS: Using standard immunohistochemical techniques, we examined 10 TEs and 19 BCCs for the expression of CK19, Ki-67, androgen receptors (AR), CD10, and PHLDA1. RESULTS: Immunoreactivity of AR, Ki-67, and CD10 in tumor cells was significantly higher in BCC than TE with a diagnostic accuracy in BCC of 75.5%, 75.8%, and 79.3% respectively, whereas immunoreactivity of PHLDA1 in tumor cells and stromal CD10 was significantly higher in TE than BCC with a diagnostic accuracy in TE of 100% and 82.8%, respectively. In contrast, immunoreactivity for CK19 showed no statistically significant differences between both tumors. CONCLUSION: The analysis of CD10, Ki-67, and PHLDA1 can be used as a helpful immunohistochemical panel in the distinction between TE and BCC especially in small and superficial biopsies.

[Microcystic adnexal carcinoma: A case report]. / Carcinome annexiel microkystique : à propos d'une observation.

We report a case of microcystic adnexal carcinoma in a 80-year-old woman. This is a rare malignant adnexal cutaneous tumor with glandular and follicular differentiation, rare, often asymptomatic, with late diagnosis and slow growth, locally aggressive and rarely metastatic. The distinction with other benign and malignant skin tumors is difficult.

Microcystic Adnexal Carcinoma and a Summary of Other Rare Malignant Adnexal Tumours.

OPINION STATEMENT: Microcystic adnexal carcinoma (MAC) is a rare, slow-growing, infiltrative malignant tumour most commonly found on the head and neck. It often presents as a solitary skin-coloured or yellow papule, plaque or nodule. Ultraviolet radiation, immunosuppression and ionising radiation are possible risk factors. Clinical and histological differential diagnoses include morpheaform basal cell carcinoma and desmoplastic trichoepithelioma. The diagnosis is usually made by skin biopsy, and the characteristic features are small keratin-filled cysts with nests and cords which resemble ductal structures. Immunohistochemistry can assist in differentiating MAC from other tumours. The local aggressive nature of the tumour and its potential to infiltrate beyond the assessed clinical margins warrant complete excision with marginal control, and we recommend Mohs micrographic surgery. Wide local excision is widely performed but is associated with recurrence given its infiltrative nature and extensive subclinical extension. The role of radiotherapy in the management of MAC is unclear.

Use of topical sirolimus in the management of multiple familial trichoepitheliomas.

The management of trichoepitheliomas is challenging, especially in children. This challenge is exemplified in patients with multiple trichoepitheliomas who present with progression of lesion count and size despite treatment with current strategies, including CO2 laser and surgery. We present the novel use of topical 1% sirolimus cream in two siblings with multiple facial trichoepitheliomas; one was treated with a combination of CO2 laser ablation and topical sirolimus, and the other was treated with topical sirolimus alone. Both siblings had a reduction in the growth of new lesions with no reported side effects. This is the first report demonstrating that topical sirolimus, either in combination with CO2 laser or alone, can be a promising treatment for trichoepitheliomas.

Desmoplastic trichoepithelioma with pseudocarcinomatous hyperplasia: a report of three cases.

We report three cases of desmoplastic trichoepithelioma (DTE) with overlying pseudocarcinomatous hyperplasia. All three cases developed on the face of patients in their second decade. In spite of their young age, a diagnosis of squamous cell carcinoma was considered for each case, given the unusual juxtaposition of these two well-known simulators of malignancy. Awareness of this potential association may avert a misdiagnosis of malignancy.

Dermoscopic Findings in Trichoblastoma.

Trichoblastoma is a benign cutaneous neoplasm that is clinically and histologically similar to basal cell carcinoma. We report the dermoscopic features seen in 2 cases of facial trichoblastoma. One case presented with very short, delicate, scarcely branching telangiectases against a pearly white background. In the second case, the veins were also short and scarcely branching, but they were arranged in a crown pattern, with white striae and milia-like cysts. Although dermoscopic evidence of fine, scarcely branching telangiectases is not specific to a diagnosis of trichoblastoma, these features may be useful for differentiating this neoplasm from nodular basal cell carcinoma.

Pathological, histochemical, and immune-histochemical studies on some canine-skin neoplasm at Sharkia province, Egypt.

Background: Cutaneous neoplastic disorders are often observed in small mammal pets, such as dogs, regardless of their gender. Aim: An important objective of this work was to give a full account of the clinical, pathological, and immune-histochemical features of several skin tumors in dogs. Methods: This study was a case series in the hospital clinic, Faculty of Veterinary Medicine, Zagazig University, Egypt. Twenty-five dogs (14 males and 11 females) were examined clinically during the period from March 2022 to October 2023. The skin swelling was collected from affected animals and then subjected to a detailed histopathological study to record the different gross and microscopic findings and confirm the diagnosis by immunohistochemistry. Results: Skin neoplasia in dogs was exposed to various clinical signs, and the dogs' ages ranged between 3 and 11 years. Concerning tumor features, the majority of neoplasms were malignant (65.52%) more than benign (34.48%). The study revealed the presence of 29 cases of dogs showed neoplasia with different prevalence rates including squamous cell carcinoma (13.79%), mast cell tumor (6.89%), basal cell tumors (10.34%), histiocytoma (6.89%), trichoepithelioma (10.34%), transmissible venereal tumor (10.34%), trichilemmoma (3.44%), scalp paraganglioma (3.44%), pilomatricoma (10.34%), malignant melanomas (17.24%), and miscellaneous cases as fat necrosis (6.89%), in males and females dogs with different histopathological lesions and immunohistochemistry expressions for pan-cytokeratin (CK), melanocyte-differentiation antigens (S100 protein), and synaptophysin. Conclusion: Malignant melanomas (17.24%) are the extremely common cutaneous tumors diagnosed in this study. Meanwhile, benign tumors such as trichilemmoma, trichoepithelioma, pilomatricoma, and paraganglioma are less frequent in dogs.

Infiltrative Basal Cell Carcinoma (iBCC) Adjacent to a Desmoplastic Trichoepithelioma (DTE): A Case Report and Literature Review of iBCCs and DTEs.

The co-existence of an infiltrative basal cell carcinoma (iBCC) and a desmoplastic trichoepithelioma (DTE) within the same cutaneous lesion is a rare occurrence. iBCCs are relatively common malignant skin neoplasms that pose a risk for local tissue destruction and recurrence. DTEs are cutaneous neoplasms originating from hair follicles that may clinically and histologically appear similar to iBCCs but are ultimately benign. Distinguishing between these two entities is important given their differing destructive potential. Herein, we describe the case of a 36-year-old female with a single skin lesion on her left cheek that was comprised of both an iBCC distinct from a DTE, as verified by histopathologic analysis. A literature review highlights the rarity of such collision tumors and discusses the potential genetic links between these two histologically similar cutaneous neoplasms.

A Misdiagnosed Familiar Brooke-Spiegler Syndrome: Case Report and Review of the Literature.

Aim of the report: Brooke-Spiegler syndrome (BSS) is a rare autosomal dominant disease characterized by the growth of cylindromas, spiradenomas, trichoepitheliomas, or their combination. These neoplasms usually begin in the second decade and progressively increase in number and size over the years. Diagnosis necessitates consideration of family history, clinical examination, histological findings, and genetic analysis. The aim of this paper is to explore the clinical overlap between Brooke-Spiegler syndrome (BSS) and neurofibromatosis type 1 (NF1). We aim to highlight the challenges associated with their differential diagnosis and emphasize the lack of standardized diagnostic criteria and treatment approaches. Case presentation: Hereby, we introduce the case of a 28-year-old male referred for suspicion of neurofibromatosis type 1 (NF1) who initially declined the recommended surgical excision for a scalp mass. After four years, he returned with larger masses of the scalp, and underwent excision of multiple masses, revealing cylindromas, spiradenomas, and spiradenocylindromas. Family history reported similar tumors in his father, who was also diagnosed with NF1 for the presence of multiple subcutaneous lesions on the scalp. Clinical overlap led to a genetic consultation, but testing for CYLD mutations yielded no significant variations. Despite this, the strong family history and consistent findings led to a revised diagnosis of Brooke-Spiegler syndrome, correcting the initial misdiagnosis of NF1 syndrome. Conclusions: Thanks to the evolving landscape of BSS research over the past two decades, its molecular underpinnings, clinical presentation, and histopathological features are now clearer. However, a thorough family history assessment is mandatory when BSS is suspected. It is our belief that a multidisciplinary approach and cooperation between specialists are essential when dealing with BSS. By sharing this case, we hope to underscore the importance of considering BSS as a differential diagnosis, especially in cases with atypical presentations or overlapping features with other syndromes like NF1.

Value of CD10 Expression in Differentiating Cutaneous Basal from Squamous Cell Carcinomas and Basal Cell Carcinoma from Trichoepithelioma.

BACKGROUND: In addition to the well-defined histological criteria for squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), immunohistochemical techniques can be used in difficult cases for their differentiation. As differential diagnosis between trichoepithelioma (TE) and BCC is sometimes difficult for the clinician and the pathologist, CD10 may be a useful marker for definite diagnosis. We aimed to evaluate the usefulness of this marker in the differentiation between SCC and BCC and also in the differentiation between BCC and TE. METHODS: Fifty-five BCC cases, 50 SCC cases, and 20 cases of benign adnexal tumor with follicular differentiation were retrieved from the archives of the pathology departments of hospitals affiliated with Shiraz University of Medical Sciences. Immunohistochemistry for CD10 was performed on the sections obtained from formalin-fixed, paraffin-embedded blocks. CD10 immunoreactivity in the stroma and/or tumor cells was determined as follows: negative (0); 1+(10-50% positive cells); and 2+(>50% positive cells). RESULTS: Comparison of CD10 expression between the BCC and SCC groups showed a significant difference (P<0.001) in each of the tumor and stromal cells. Comparison of CD10 expression between the BCC and TE groups demonstrated a significant difference in both the tumor and stromal cells (P<0.001). There was no significant difference in CD10 expression between the stromal and tumor cells of the BCC subtypes. CONCLUSION: CD10 is a useful adjunct marker in distinguishing TE from BCC. CD10 is suggested to be one of the useful immunohistochemical markers to differentiate BCC from SCC.

Enemy in disguise: A case report of solitary trichoepithelioma initially diagnosed as BCC.

INTRODUCTION: Solitary trichoepitheliomas (TE) are benign tumors that are strikingly similar to their malignant counterpart, basal cell carcinoma (BCC). PRESENTATION OF CASE: An 83-year-old man presented with a 10-year history of a right lower lid skin mass initially diagnosed as BCC. Intraoperatively, an excisional biopsy was performed with primary reconstruction of the skin defect and the specimen was submitted for histopathology processing. Eventually, histopathology findings suggested the diagnosis of benign hair follicle tumor. The postoperative results were aesthetically pleasing and the integrity of the lower lid was preserved. DISCUSSION: Despite being rare, benign solitary TE are frequently misdiagnosed as malignant BCC, and vice versa. Oculoplastic surgeons face considerable difficulty distinguishing the two pathologies due to their similar clinical and histological pictures. Hence, excisional biopsy should be considered whenever such discrepancy is confronted to avoid the possibility of recurrence or malignant transformation. Furthermore, immunohistochemical staining could increase the accuracy of diagnosis in such unequivocal findings. CONCLUSION: Correlation of clinical, dermoscopic and histopathological findings are essential to establish an accurate diagnosis and select the appropriate management. In-depth understanding of eyelid reconstruction principles is mandatory to achieve desirable goals.

Expression of BerEP4 and CD10 IHC Markers in Basal Cell Carcinoma, Squamous Cell Carcinoma and Adnexal Tumours of Follicular Differentiation: A Comparative Study.

Background: Basal cell carcinoma (BCC) is the most common cutaneous malignancy. In most cases, BCC can be diagnosed by its characteristic histopathological features. The differential diagnosis includes basaloid squamous cell carcinoma (SqCC) and adnexal tumours of follicular differentiation. Cluster of differentiation 10 (CD10) and name of an immunostain (BerEP4) are reported to be useful in differentiating between them. Objectives: The primary objective was to compare the expression of BerEP4 and CD10 in BCC with that of SqCC and adnexal tumours of follicular differentiation, and the secondary objective was to evaluate the proportion of different histological subtypes of BCC. Materials and Methods: Twenty-eight cases of BCCs, 34 cases of SqCCs and 16 adnexal tumours of follicular differentiation received in the institution during the study period January 2017 to June 2018 were included in this descriptive study. Immunostaining with CD10 and BerEP4 was performed, and the staining pattern was studied in all 78 cases. A detailed histopathological evaluation including subtyping was carried out for BCC cases. Results: All BCCs showed positivity with CD10 and BerEP4, but the intensity and pattern varied. Squamous cell carcinomas were completely negative for BerEP4 and CD10 in tumour cells, and 25 of 34 cases showed stromal CD10 positivity. Among adnexal tumours of follicular differentiation, proliferating trichilemmal tumour was completely negative for both markers; other adnexal tumours (n = 11/16) showed peritumoral stromal accentuation for CD10, and nine of 11 cases showed BerEP4 tumour cell positivity (P < 0.001). Conclusion: BerEP4 can reliably detect BCCs of all types and distinguish between BCC and SqCC, but it is unable to do so for adnexal tumours such as trichoepithelioma, trichilemmoma and trichoblastoma. CD10 is a useful adjunct marker in distinguishing both trichoepithelioma (TE) and SqCC from BCC. CD10-positive tumour cells favour a diagnosis of BCC and peritumoral stromal accentuation for trichoblastoma (TB) and trichilemmoma (TL). Tumour cells in SqCC are almost always negative for CD10. A combined immunohistochemistry (IHC) panel of CD10 and BerEP4 can serve as a very reliable adjunctive in the diagnosis of BCC.

Multiple Trichoepithelioma Syndrome: A Case Report.

Multiple trichoepithelioma syndrome is a rare entity, and little is known about its epidemiological features. Patients usually present with multiple nonsuspicious skin lesions. Surgical excision is the mainstay of treatment, and diagnosis is usually made after the first pathology report. Once the diagnosis is established, patients are kept under clinical surveillance, and surgery is performed again if tumor burden and/or size justifies it. The authors present a male patient who presented to our outpatient clinic for the first time in 36 years without any relevant medical history, medication, or allergies. The patient had complaints of multiple skin lesions spreading across the head and neck regions. Surgical excision of the affected area and resurfacing using local advancement flaps were performed. Pathology reports were always consistent with trichoepitheliomas. No pathology of spiradenoma or cylindroma was ever reported. Usually, tumors are small enough for simple excision and primary closure. However, in the presented case, the size of the tumor and the involvement of central facial aesthetic units demanded a more complex approach.