Patients with a new-onset cutaneous sebaceous neoplasm following immunosuppression should be evaluated for Muir-Torre syndrome with germline mismatch repair gene mutation analysis: case reports.

Patients with Muir-Torre syndrome may have a systemic malignancy and a sebaceous neoplasm such as an adenoma, epithelioma, and/or carcinoma. The syndrome usually results from a germline mutation in one or more mismatch repair genes. Iatrogenic or acquired immunosuppression can promote the appearance of sebaceous tumors, either as an isolated event or as a feature of Muir-Torre syndrome and may unmask individuals genetically predisposed to the syndrome. Two iatrogenically immunosuppressed men with Muir-Torre syndrome features are described. Similar to these immunocompromised men, Muir-Torre syndrome-associated sebaceous neoplasms have occurred in solid organ transplant recipients, human immunodeficiency virus-infected individuals, and patients with chronic diseases who are treated with immunosuppressive agents. Muir-Torre syndrome-associated sebaceous neoplasms occur more frequently and earlier in kidney recipients, who are receiving more post-transplant immunosuppressive agents, than in liver recipients. The development of sebaceous neoplasms is decreased by replacing cyclosporine or tacrolimus with sirolimus or everolimus. Specific anti-cancer vaccines or checkpoint blockade immunotherapy may merit exploration for immune-interception of Muir-Torre syndrome-associated sebaceous neoplasms and syndrome-related visceral cancers. We suggest germline testing for genomic aberrations of mismatch repair genes should routinely be performed in all patients-both immunocompetent and immunosuppressed-who develop a Muir-Torre syndrome-associated sebaceous neoplasm.

Establishment and Characterization of a TP53-Mutated Eyelid Sebaceous Carcinoma Cell Line.

Purpose: Eyelid sebaceous carcinoma (SeC) is the third most frequent eyelid malignancy worldwide and is relatively prevalent in Asian patients. An eyelid SeC cell line model is necessary for experimental research to explore the etiology and pathogenesis of eyelid SeC. This study established and characterized an eyelid SeC cell line with a TP53 mutation that might be useful for analyzing potential treatment options for eyelid SeC. Methods: The eyelid SeC cell line SHNPH-SeC was obtained from a patient with eyelid SeC at Shanghai Ninth People's Hospital (SHNPH), Shanghai JiaoTong University School of Medicine. Immunofluorescence staining was employed to detect the origination and proliferation activity. Short tandem repeat (STR) profiling was performed for verification. Chromosome analysis was implemented to investigate chromosome aberrations. Whole exome sequencing (WES) was used to discover genomic mutations. Cell proliferation assays were performed to identify sensitivity to mitomycin-C (MMC) and 5-fluorouracil (5-FU). Results: SHNPH-SeC cells were successively subcultured for more than 100 passages and demonstrated rapid proliferation and migration. Karyotype analysis revealed abundant chromosome aberrations, and WES revealed SeC-related mutations in TP53, KMT2C, and ERBB2. An in vivo tumor model was successfully established in NOD/SCID mice. Biomarkers of eyelid SeC, including cytokeratin 5 (CK5), epithelial membrane antigen (EMA), adipophilin, p53, and Ki-67, were detected in SHNPH-SeC cells, original tumors, and xenografts. MMC and 5-FU inhibited the proliferation and migration of SHNPH-SeC cells, and SHNPH-SeC cells presented a greater drug response than non-TP53-mutated SeC cells. Conclusions: The newly established eyelid SeC cell line SHNPH-SeC demonstrates mutation in TP53, the most commonly mutated gene in SeC. It presents SeC properties and malignant characteristics that may facilitate the investigation of cellular behaviors and molecular mechanisms of SeC to explore promising therapeutic strategies.

Base-Excision Repair Mutational Signature in Two Sebaceous Carcinomas of the Eyelid.

Personalized medicine aims to develop tailored treatments for individual patients based on specific mutations present in the affected organ. This approach has proven paramount in cancer treatment, as each tumor carries distinct driver mutations that respond to targeted drugs and, in some cases, may confer resistance to other therapies. Particularly for rare conditions, personalized medicine has the potential to revolutionize treatment strategies. Rare cancers often lack extensive datasets of molecular and pathological information, large-scale trials for novel therapies, and established treatment guidelines. Consequently, surgery is frequently the only viable option for many rare tumors, when feasible, as traditional multimodal approaches employed for more common cancers often play a limited role. Sebaceous carcinoma of the eyelid is an exceptionally rare cancer affecting the eye's adnexal tissues, most frequently reported in Asia, but whose prevalence is significantly increasing even in Europe and the US. The sole established curative treatment is surgical excision, which can lead to significant disfigurement. In cases of metastatic sebaceous carcinoma, validated drug options are currently lacking. In this project, we set out to characterize the mutational landscape of two sebaceous carcinomas of the eyelid following surgical excision. Utilizing available bioinformatics tools, we demonstrated our ability to identify common features promptly and accurately in both tumors. These features included a Base-Excision Repair mutational signature, a notably high tumor mutational burden, and key driver mutations in somatic tissues. These findings had not been previously reported in similar studies. This report underscores how, in the case of rare tumors, it is possible to comprehensively characterize the mutational landscape of each individual case, potentially opening doors to targeted therapeutic options.

Immunohistochemistry, Molecular Biology, and Clinical Scoring for the Detection of Muir-Torre Syndrome in Cutaneous Sebaceous Tumors: Which Strategy?

BACKGROUND: Sebaceous neoplasms (SNs) always raise the possibility of an association with Muir-Torre syndrome (MTS) and permit to screen internal malignancies, colorectal and endometrial carcinomas, before they become symptomatic. Immunohistochemistry (IHC), molecular biology, and clinical examination are different approaches for detection of MTS. We conducted a retrospective analysis of non-selected SNs in order to determine the optimal tools to implement for MTS screening. METHODS: Deficient MMR phenotype (dMMR) was determined by either IHC using antibodies directed to four mismatch repair (MMR) antigens on tissue microarray or molecular biology using pentaplex PCR. The Mayo Clinic risk score of MTS was calculated from medical records. Sensibility and specificity of each test for the detection of MTS were determined. RESULTS: We included 107 patients, 8 with multiple SNs, for a total of 123 SNs (43 sebaceous adenomas, 19 sebaceomas, and 61 sebaceous carcinomas (SC)). Loss of at least one MMR protein was observed in 70.7% of tumors, while 48% had a microsatellite instable phenotype. Concordance between both techniques was 92.9%, with a 0.85 Cohen's kappa coefficient. Nineteen patients (20.2%) had a ≥2 points Mayo Clinic risk score, one having a pMMR SC. Among the 13 patients with confirmed MTS, 2 had a low Mayo Clinic risk score (1 point). IHC had the highest sensitivity for MTS screening (100%) with a specificity of 34.1%, while a >2-point Mayo Clinic risk score had a lower sensitivity (92%) but a higher specificity (89%). CONCLUSION: To detect MTS in SN patients, the first-line Mayo Clinic risk score followed by IHC appears to be the most accurate strategy with lower cost for society. This strategy should be adapted to the medico-economic resources of each country.

Muir-Torre syndrome and recent updates on screening guidelines: The link between colorectal tumors and sebaceous adenomas in unusual locations.

BACKGROUND: Muir-Torre syndrome (MTS) is a rare genetic disorder that is caused by mismatch repair (MMR) protein mutations. MTS increases the risk of developing skin and gastrointestinal tumors such as sebaceous adenomas (SAs), sebaceous carcinomas, colorectal cancer, endometrial cancer, and ovarian cancer. The risk of developing these types of tumors varies depending on the involved mutation and the individual's family history risk. CASE PRESENTATION: A 47-year-old male presented with multiple skin lesions on the scalp, face, flank, and back. The examination revealed well-circumscribed, dome-shaped papules with a yellowish appearance with white oily material in the center. Histopathologic examination showed a well-circumscribed sebaceous neoplasm consistent with a mixture of basaloid cells and lobules of bland-appearing mature adipocytes that communicate directly to the surface epithelium. Focal cystic changes and peritumoral lymphocytic infiltrate were noted. Increased mitotic figures were seen in the basaloid cell component. The overall findings were consistent with the diagnosis of SAs. MMR staining showed preserved expression in MLH1 and PMS2 proteins, while MSH2 and MSH6 staining showed loss of protein expression. A screening colonoscopy showed numerous colon and rectal tumors, prompting concerns about the likelihood of MTS. Surgical intervention was pursued for complete resection. Histology revealed a diagnosis of mucinous adenocarcinoma/adenocarcinoma with mucinous features of the colon. The diagnosis of MTS was supported by molecular testing that revealed MSH2 germline mutation. The increased likelihood of MTS was attributed to the occurrence of SAs in unusual locations of the head and neck regions, unlike typical cases. CONCLUSION: MTS is a rare clinical condition that necessitates prompt thorough evaluation and periodic surveillance. When SA is encountered in atypical locations, it is important to consider additional testing supported by immunohistochemical staining, molecular testing, and regular screening to exclude the likelihood of MTS.

The M2 macrophages infiltration of sebaceous tumors is linked to the aggressiveness of tumors but not to the mismatch repair pathway.

PURPOSE: The immune microenvironment of sebaceous neoplasms (SNs) has been poorly explored, especially in benign lesions, and never correlated to the mismatch repair (MMR) status. METHODS: We conducted an immuno-histological study to analyze the immune microenvironment of SNs. A tissue microarray was constructed including sebaceous adenomas (SAs), sebaceomas (Ss) and sebaceous carcinomas (SCs) to performed immuno-histological analysis of T cells, B cells, macrophages, dendritic cells, and expression of Programmed Death-1 (PD-1) and Programmed Death Ligand 1 (PD-L1). An automatized count was performed using the QuPath® software. Composition of the cellular microenvironment was compared to the aggressiveness, the MMR status, and to Muir-Torre syndrome (MTS). RESULTS: We included 123 SNs (43 SAs, 19 Ss and 61 SCs) for which 71.5% had a dMMR phenotype. A higher infiltration of macrophages (CD68 +) of M2 phenotype (CD163 +) and dendritic cells (CD11c +) was noticed in SCs compared to benign SNs (SAs and Ss). Programmed cell death ligand-1 but not PD-1 was expressed by more immune cells in SCs compared to benign SNs. No difference in the immune cell composition regarding the MMR status, or to MTS was observed. CONCLUSION: In SNs, M2 macrophages and dendritic cells infiltrates are associated with the progression and the malignant transformation of tumors. High PD-L1 expression in immune cells in SCs is an argument for the use of immunotherapy by anti-PD1 or PD-L1 in metastatic patients. The lack of correlation between the composition of immune cells in SNs and the MMR status emphasizes the singularity of SNs among MMR-associated malignancies.

Characterization of sebaceous and non-sebaceous cutaneous manifestations in patients with lynch syndrome: a systematic review.

A subset of patients with Lynch Syndrome demonstrates cutaneous manifestations of the disorder. Characterization of these Lynch-related skin lesions could help in early recognition of patients with Lynch Syndrome. A broad search of the literature on OVID Medline and Embase was carried out to capture papers reporting cutaneous manifestations in Lynch Syndrome patients. The results were uploaded into Mendeley reference management software. The PRISMA workflow was used in the literature selection process. In this systematic review, data were collected from 961 cases from 413 studies, including 380 molecularly confirmed Lynch Syndrome cases. The main skin lesions were: Sebaceous adenomas (43%), sebaceous carcinomas (27%), keratoacanthomas (16%), sebaceomas (13%), squamous cell carcinomas (23%), and basal cell carcinomas (10%). MSH2 variants were the most common underlying genotype (72%). Assessment of mismatch repair by immunohistochemistry, microsatellite instability analysis, or both were performed on 328 skin lesions from 220 (58%) molecularly confirmed cases. In those skin lesions, 95% of Immunohistochemistry and 90% of the microsatellite instability test results were concordant with the underlying genotype. Sebaceous skin lesions are well-recognised phenotypic features of Lynch Syndrome. Our results show that squamous and basal cell carcinomas are relatively common in patients with Lynch syndrome; however, available evidence cannot confirm that Lynch syndrome is causal. Immunohistochemistry and/or microsatellite instability testing of skin tumours in patients with a family history of Lynch Syndrome-associated cancers may be a useful approach in identifying patients requiring referral to Clinical Genetics and/or consideration of germline genetic testing for Lynch Syndrome.

Combination treatment of bilateral periocular sebaceous carcinomas with microsatellite instability with neoadjuvant pembrolizumab and Mohs surgery.

This case highlights the successful use of pembrolizumab for neoadjuvant treatment of MMR-deficient sebaceous carcinoma of bilateral eyelids to reduce tumour burden allowing smaller defect post-Mohs surgery and better reconstructive outcome. Microsatellite stability, tumour mutational burden and PD-L1 expression are important prognostic factors to be considered for the use of neoadjuvant pembrolizumab. Further studies are needed to determine if neoadjuvant pembrolizumab consistently improves surgical and cosmetic outcomes and reduces local recurrence and metastasis.

Impaired Wnt/beta-catenin and protein patched homolog 1 signaling in extraocular sebaceous carcinoma: A clinical and histopathological study.

Sebaceous carcinoma (SC) is a rare malignant neoplasm with sebaceous differentiation. SC is classified into eyelid and extraocular SC clinically. Most studies have focused on the eyelid SC in terms of pathogenesis, treatment, and prognosis. In skin, Wnt/beta-catenin and hedgehog signaling are two major pathways in sebaceous differentiation. We aimed to characterize the clinical and histopathological features of extraocular SC and to measure the expression of beta-catenin, lymphoid enhancer-binding factor 1 (LEF1), sonic hedgehog (Shh), and protein patched homolog 1 (PTCH) in extraocular SC. Ten cases of extraocular SC were identified from 2007 to 2020. The clinical features, microscopic findings, and prognosis were analyzed. Immunohistochemical stain for beta-catenin, LEF1, Shh, and PTCH were performed in extraocular SC and other benign sebaceous tumors including sebaceous hyperplasia, sebaceous adenoma, and sebaceoma. The male:female ratio was 4:6. The median onset age was 73.5 years (range, 43-88). Seven patients out of 10 were diagnosed after 60 years. Most extraocular SC were located on the head and neck with indurated plaque. Two patients had concurrent internal cancers and three patients showed lymph node metastasis at time of presentation. Five-year overall-survival was 40%. Beta-catenin was expressed membranously in all sebaceous hyperplasia, but was expressed variably in extraocular SC (1/5). While LEF1 was unequivocally expressed in normal hair follicles, LEF1 expression was absent in all extraocular SC and benign sebaceous tumors. Regarding the sonic hedgehog signaling, Shh and PTCH were all expressed in the cytoplasm of sebaceous hyperplasia, sebaceous adenoma, and sebaceoma. In contrast, PTCH was absent in all cases of extraocular SC and only 50% of the extraocular SC expressed cytoplasmic Shh. To conclude, extraocular SC commonly affects facial skin in the elderly. Inactivated Wnt/beta-catenin and aberrant hedgehog pathway may contribute to the carcinogenesis of extraocular SC. Further studies may be required to elucidate the causative mechanism of these pathways in extraocular SC.

[Epigenetic changes in the promoter of the fragile histidine triad (FHIT) gene in human sebocytes under the influence of in vitro culture]. / Epigenetische Veränderungen am Promotor des fragilen Histidin-Trias(FHIT)-Gens in menschlichen Sebozyten unter dem Einfluss der In-vitro-Kultur.

BACKGROUND: Due to the lack of tumor suppressor function of the fragile histidine triad (FHIT) gene product, sebaceous gland carcinomas can develop. OBJECTIVE: The model of the sebocyte cell line SZ95 was used to identify methylated CpG islands at the 5'-end of the FHIT gene and the decrease of gene expression as well as the increase of double-stranded (ds) DNA breaks were examined. MATERIAL AND METHODS: Methylation, immunofluorescence analysis, promotor sequencing and treatment of SZ95 cells with 5­azacytidine/trichostatin A (TSA). RESULTS: The cultivation was accompanied by an increasing methylation of the CpG islands, a decrease of the FHIT gene expression and an accumulation of ds-DNA breaks. Treatment with 5­azacytidine/TSA showed a decrease in DNA methylation and a re-expression of FHIT transcripts. DISCUSSION: Epigenetic changes in the cellular genome are caused by in vitro cell culture. Consequently, a positive selection of sebocytes with an epigenetically inactivated FHIT locus occurs.

Molecular pathology of skin adnexal tumours.

AIMS: Tumours of the cutaneous adnexa arise from, or differentiate towards, structures in normal skin such as hair follicles, sweat ducts/glands, sebaceous glands or a combination of these elements. This class of neoplasms includes benign tumours and highly aggressive carcinomas. Adnexal tumours often present as solitary sporadic lesions, but can herald the presence of an inherited tumour syndrome such as Muir-Torre syndrome, Cowden syndrome or CYLD cutaneous syndrome. In contrast to squamous cell carcinoma and basal cell carcinoma, molecular changes in adnexal neoplasia have been poorly characterised and there are few published reviews on the current state of knowledge. METHODS AND RESULTS: We reviewed findings in peer-reviewed literature on molecular investigations of cutaneous adnexal tumours published to June 2021. CONCLUSIONS: Recent discoveries have revealed diverse oncogenic drivers and tumour suppressor alterations in this class of tumours, implicating pathways including Ras/MAPK, PI3K, YAP/TAZ, beta-catenin and nuclear factor kappa B (NF-κB). These observations have identified novel markers, such as NUT for poroma and porocarcinoma and PLAG1 for mixed tumours. Here, we provide a comprehensive overview and update of the molecular findings associated with adnexal tumours of the skin.

NGS Analysis Confirms Common TP53 and RB1 Mutations, and Suggests MYC Amplification in Ocular Adnexal Sebaceous Carcinomas.

Ocular adnexal (OA) sebaceous carcinomas generally demonstrate more aggressive clinical and histopathological phenotypes than extraocular cases, but the molecular drivers implicated in their oncogenesis remain poorly defined. A retrospective review of surgical and ocular pathology archives identified eleven primary resection specimens of OA sebaceous carcinomas with adequate tissue for molecular analysis; two extraocular cases were also examined. Next-generation sequencing was used to evaluate mutations and copy number changes in a large panel of cancer-associated genes. Fluorescence in situ hybridization (FISH) confirmed MYC copy number gain in select cases, and immunohistochemistry to evaluate MYC protein expression. The commonest mutations occurred in TP53 (10/13) and RB1 (7/13). Additional mutations in clinically actionable genes, or mutations with a frequency of at least 25%, included the NF1 (3/12), PMS2 (4/12), ROS1 (3/12), KMT2C (4/12), MNX1 (6/12), NOTCH1 (4/12), PCLO (3/12), and PTPRT (3/12) loci. Low level copy number gain suggestive of amplification of the MYC locus was seen in two cases, and confirmed using FISH. MYC protein expression, as assessed by immunohistochemistry, was present in almost all sebaceous carcinoma cases. Our findings support the concept that alterations in TP53 and RB1 are the commonest alterations in sebaceous carcinoma, and suggest that MYC may contribute to the oncogenesis of these tumors.

Molecular Genetics of Sebaceous Neoplasia.

Sebaceous neoplasia primarily includes sebaceous adenoma, sebaceoma, and sebaceous carcinoma (SC). Sebaceous adenoma, sebaceoma, and a subset of cutaneous SC are frequently associated with defective DNA mismatch repair resulting from mutations in MLH1, MSH2, or MSH6. These tumors can be sporadic or associated with Muir-Torre syndrome. SCs without defective DNA mismatch repair have ultraviolet signature mutation or paucimutational patterns. Ocular SCs have low mutation burdens and frequent mutations in ZNF750. Some ocular sebaceous carcinomas have TP53 and RB1 mutations similar to cutaneous SC, whereas others lack such mutations and are associated with human papilloma virus infection.

TERT promoter mutation in sebaceous neoplasms.

TERT promoter (TERTp) mutations widely occur in multiple human neoplasms, and they have been related to different clinicopathological features. To date, this mutation has not been identified in sebaceous tumors. Here, we analyzed TERTp mutations in 91 sebaceous neoplasms (17 adenomas, 45 sebaceomas, and 29 carcinomas). We detected mutations in 26.7% (8 of 29) of sebaceous carcinomas by pyrosequencing and Sanger sequencing. No mutation was detected in adenomas or sebaceomas. The difference was significant between sebaceoma and carcinoma. The most frequent TERTp mutations were C228T and C250T in 37.5% (3 of 8) of mutated cases each one. The mutation was not associated with poor clinical evolution. Using NGS, 20 of 29 (68.5%) sebaceous carcinomas harbored mutations in 8 of the 30 genes analyzed (TP53, TERTp, EGFR, ATRX, PDGFRA, CDKN2A, PTEN, and ACVR1). With immunohistochemistry, only 1 of 8 (12.5%) TERTp-mutated carcinomas lacked mismatch repair (MMR) protein expression compared to 6 of 21 (31.6%) of non-mutated ones. Sebaceous carcinomas with MMR protein expression had significantly higher frequency of total mutations and TP53 and TERTp mutations than MMR protein-deficient carcinomas. In conclusion, TERTp mutation has been detected in sebaceous carcinomas, and its presence could be useful to differentiate sebaceous carcinoma from sebaceoma, a difficult histopathological challenge.

High-risk human papillomavirus and ZEB1 in ocular adnexal sebaceous carcinoma.

BACKGROUND: Ocular adnexal (OA) sebaceous carcinoma is an aggressive malignancy. Oncologic drivers of ocular sebaceous carcinoma are incompletely understood. METHODS: A retrospective search of our pathology archives for OA sebaceous carcinoma identified 18 primary resection specimens. Immunohistochemistry for p16 and ZEB1 and RNA in situ hybridization for high-risk human papillomavirus (HPV) subtypes were performed. RESULTS: High-risk HPV was demonstrated in 2/11 (18%) cases. p16 overexpression was observed in 10/11 (91%). No association between gender, age at presentation, tumor location, intraepithelial spread, tumor size, and T stage was observed between HPV-driven and nonviral cases. High expression of ZEB1 was observed in the intraepithelial component of 4/14 (28%) cases and in the subepithelial component of 1/13 (7%) cases. ZEB1 overexpression was not associated with HPV status, T stage, or tumor size. CONCLUSION: As previously described by others, our findings suggest that a subset of OA sebaceous carcinomas may arise via an HPV-dependent pathway. However, unlike high-risk HPV-driven carcinomas of the oropharynx, we did not identify an association between HPV-status and prognostic features. Furthermore, p16 expression was not a useful surrogate marker for HPV-driven disease. ZEB1 overexpression is not associated with HPV in our cohort of ocular sebaceous carcinoma.

A case of Muir-Torre syndrome with a keratoacanthoma and sebaceous neoplasms: Clinicopathological features and a speculation on the pathogenesis of cutaneous tumor type.

Muir-Torre syndrome is a hereditary condition characterized by occurrence of sebaceous neoplasms or keratoacanthomas and visceral tumors. The most common mechanism for this syndrome is a constitutional defect in the mismatch repair genes. We report the case of a 67-year-old woman with a mutator L homologue 1 (MLH1) mutation. She had a history of endometrial and colorectal cancers. The patient presented with a typical keratoacanthoma on the right cheek and numerous sebaceous neoplasms on the face and trunk. Seven sebaceous adenomas and a low-grade sebaceous carcinoma were excised. Most sebaceous adenomas showed dermoscopic features such as some yellow comedo-like globules and curved vessels in creamy-white areas. Moreover, they revealed pathological features such as keratoacanthoma-like architecture and peritumoral or intratumoral lymphocytes. One of these sebaceous adenomas indicated histopathologically spontaneous regression and another was continuous with the hair follicle. Immunohistochemical staining for mismatch repair proteins revealed loss of expression for MLH1 and postmeiotic segregation increased 2 (PMS2) proteins in tumor cells nuclei in both keratoacanthoma and sebaceous adenoma. Nuclei in overhanging epithelial lips of the keratoacanthoma were also negative. These findings suggest that the type of Muir-Torre syndrome-related cutaneous tumor may have been affected by mismatch repair protein deficient sites in the pilosebaceous unit.