Distinct Biological Types of Ocular Adnexal Sebaceous Carcinoma: HPV-Driven and Virus-Negative Tumors Arise through Nonoverlapping Molecular-Genetic Alterations

S1-Guideline Sebaceous Carcinoma

Sebaceous gland carcinomas are rare malignant cutaneous adnexal tumors with sebocytic differentiation. The typical predilection area is the head and neck region, where sebaceous gland carcinomas are the most common malignant adnexal tumors of the skin. According to their localization a distinction is made between periocular and extraocular sebaceous gland carcinomas. Muir-Torre syndrome (MTS) should always be ruled out if it is suspected. In terms of prognosis, sebaceous gland carcinomas are potentially aggressive tumors with a clear tendency to recur and metastasize. Only small extraocular sebaceous gland carcinomas that have been completely resected have a very good prognosis. Sebaceous gland carcinomas most frequently metastasize lymphogenously to regional or distant lymph nodes; organ metastasis occurs less frequently. Periocular sebaceous gland carcinomas have a higher metastasis rate (up to 15%) than extraocular sebaceous gland carcinomas (up to 2%). Complete micrographically controlled surgery (MCS) of the primary tumor is the therapy of first choice, regardless of periocular or extraocular localization. Adjuvant or therapeutic radiotherapy may be considered. There is currently no established standard therapy for advanced, inoperable, or metastatic sebaceous gland carcinomas. Local procedures and systemic therapies such as chemotherapy or immunotherapy can be considered. The procedure should be determined individually by an interdisciplinary tumor board. Close follow-up care is recommended for these potentially aggressive carcinomas.

S1‐Leitlinie Talgdrüsenkarzinom

Sebaceous gland carcinomas are rare malignant cutaneous adnexal tumors with sebocytic differentiation. The typical predilection area is the head and neck region, where sebaceous gland carcinomas are the most common malignant adnexal tumors of the skin. According to their localization a distinction is made between periocular and extraocular sebaceous gland carcinomas. Muir-Torre syndrome (MTS) should always be ruled out if it is suspected. In terms of prognosis, sebaceous gland carcinomas are potentially aggressive tumors with a clear tendency to recur and metastasize. Only small extraocular sebaceous gland carcinomas that have been completely resected have a very good prognosis. Sebaceous gland carcinomas most frequently metastasize lymphogenously to regional or distant lymph nodes; organ metastasis occurs less frequently. Periocular sebaceous gland carcinomas have a higher metastasis rate (up to 15%) than extraocular sebaceous gland carcinomas (up to 2%). Complete micrographically controlled surgery (MCS) of the primary tumor is the therapy of first choice, regardless of periocular or extraocular localization. Adjuvant or therapeutic radiotherapy may be considered. There is currently no established standard therapy for advanced, inoperable or metastatic sebaceous gland carcinomas. Local procedures and system therapies such as chemotherapy or immunotherapy can be considered. The procedure should be determined individually in an interdisciplinary tumor board. Close follow-up care is recommended for these potentially aggressive carcinomas.

Prognostic Significance of Tumor-Infiltrating Lymphocytes and High-Risk Human Papillomavirus in Ocular Sebaceous Carcinoma: A Comprehensive Analysis

High-risk human papillomavirus (hrHPV) and tumor-infiltrating lymphocytes (TILs) are known to have prognostic significance in oropharyngeal squamous cell carcinoma. However, their significance in ocular sebaceous carcinoma (OSC) remains unverified because of the rarity of the condition. This study aimed to investigate the association between clinicopathologic features, biomarkers, and hrHPV infection and their potential to predict prognosis in OSC patients. We analyzed the clinicopathologic features of 81 OSC patients from Asan Medical Center between 2000 and 2022. Seventeen biomarkers and hrHPV were examined using immunohistochemistry and DNA in situ hybridization on tissue microarray cores. hrHPV was identified in 31 cases (38.3%). Univariate analysis revealed that hrHPV infection was associated with comedonecrosis (P = .032), high Ki-67 labeling index (≥30%, P = .042), lower expression of E-cadherin (P = .033), and loss of expression of zinc finger protein 750 (P = .023). Multivariate analysis revealed that loss of expression of zinc finger protein 750 (P = .026) remained an independently associated factor for hrHPV. Progression-free survival analysis was performed on 28 patients who were continuously observed for more than 5 years. During a median follow-up duration of 86 months, recurrence or metastasis developed in 14 patients (50%) within the survival cohort, occurring at a median time of 48 months after excision. Univariate analysis indicated that recurrence or metastasis was associated with tumor size (P = .010), high TILs (≥10%; P = .025), lymphovascular invasion (P = 0.043), site of origin (P = .025), and high expression of bcl-2-associated athanogene 3 (P = .039). Multivariate analysis demonstrated that high TILs (P = .017) and site of origin (P = .025) were independent prognostic factors. The prognosis of OSC was hrHPV-independent, and a better prognosis was associated with the site of origin in the order of the gland of Zeis, meibomian gland, and multicentric site, as well as with high TILs.

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.

Prevalence of human papillomavirus in eyelid carcinoma among Koreans: a clinicopathological study

BACKGROUND

Human papillomavirus (HPV) has been detected in eyelid sebaceous gland carcinoma (SGC) and squamous cell carcinoma (SCC), and detection rates greatly varied across studies. This study aimed to investigate the presence of HPV in eyelid SGC and SCC among Koreans and its correlation with clinicopathological characteristics.

METHODS

Surgically resected eyelid samples diagnosed as SGC or SCC from January 1999 to June 2011 were identified from the pathology database of three referral centres in Korea. Clinicopathological information including origin (skin vs. tarsal conjunctiva) and treatment outcomes were retrospectively reviewed. Immunohistochemistry (IHC) for p16, HPV DNA in situ hybridisation (ISH), and polymerase chain reaction-based DNA microarray were performed in paraffin-embedded tissue sections.

RESULTS

Our cohort included 34 SGC and 12 SCC cases with Asian ethnicity. HPV was detected in 4 SGC and 6 SCC by DNA microarray, while 2 SCC (16.7%) showed positivity in ISH. SCC of tarsal conjunctival origin was significantly more common in HPV-positive SCC than in HPV-negative SCC (5 of 6 vs. 0 of 6, P = 0.015, Fisher's exact test). Among samples showing positive staining in p16 IHC, HPV positivity rates were 0.0% (0/19) in SGC and 100% (3/3) in SCC. There was no significant difference in overall and local recurrence rate in eyelid SGC and SCC according to the HPV status (P > 0.99).

CONCLUSIONS

HPV was found in a subset of eyelid SGC and SCC among Koreans and might be aetiologically related to SCC of tarsal conjunctival origin. Overexpression of p16 is considered to be inappropriate as an indicator of HPV infection in eyelid SGC. Further investigation is required to elucidate the transmission route and pathogenic roles of HPV.

Genetics of adnexal tumors: An update

Cutaneous adnexal tumors form a vast heterogeneous group that include frequent entities that are mostly benign, as well as rare tumors that are occasionally malignant. In contrast to cutaneous tumors arising from the interfollicular epidermis that develop as a result of accumulation of UV-induced DNA damage (basal cell carcinoma, squamous cell carcinoma), the oncogenesis of adnexal tumors is related to a broad spectrum of genetic mechanisms (e.g., point mutation, fusion genes, viral integration, etc.). In this setting, specific and recurrent genetic alterations have been progressively reported, and these allow better classification of these entities. For certain of them, immunohistochemical tools are now available, enabling precise integrated histological and molecular diagnosis since certain entities are linked to well-defined alterations. In this context, we aim in this review to summarize the main molecular tools currently available for the classification of adnexal tumors.

HPV-associated Vulvar Intraepithelial Carcinoma With Sebaceous Differentiation: Report of 2 Cases

Sebaceous carcinoma (SC) is a malignant neoplasm demonstrating sebocytic differentiation, commonly in the periocular area. Sebocytic differentiation is recognized by multivesicular cytoplasmic clearing with frequent nuclear scalloping. The vesicles can be highlighted by immunohistochemical stains against the perilipin family proteins including adipophilin. Extraocular SC is uncommon but well reported, often in the setting of Muir-Torre syndrome; however, vulvar SC is exceptionally rare. The literature review yielded only 12 prior cases of vulvar SC, all of which showed invasion. Here we report 2 additional similar cases from 2 different institutions of an intraepithelial carcinoma with sebaceous differentiation. Histologic examination of multiple specimens from both patients showed similar features: a multifocal intraepithelial basaloid nodular neoplasm sparing the basal layer with occasional pagetoid spread. The tumor cells demonstrated a high nuclear to cytoplasmic ratio, mitoses, variably foamy vacuolated cytoplasm, and nuclear indentation. Multiple specimens from both patients showed evidence of sebaceous differentiation (substantiated by adipophilin positivity in a membranous vesicular pattern in case 1 and by androgen receptor and epithelial membrane antigen positivity in case 2), and squamous differentiation (substantiated by p63/p40 and weak CK 5/6 expression), as well as human papillomavirus (HPV) association (substantiated by p16 block positivity and detection of high-risk HPV by in situ hybridization). One case was a true in situ lesion without evidence of invasion, and the other case was predominantly an in situ carcinoma with prominent adnexal extension and focal superficial invasion of <1 mm seen in one of multiple specimens. To our knowledge, these 2 cases are the first to show a vulvar SC/carcinoma with sebaceous differentiation that is predominantly limited to the epidermis, and the first documentation of HPV infection in vulvar sebaceous neoplasms. Vulvar intraepithelial carcinoma with sebaceous differentiation is the umbrella term we chose for this entity. Whether this is a true SC in situ that is HPV positive/driven, or a vulvar intraepithelial neoplasia with sebaceous differentiation, is not entirely clear. We emphasize the importance of looking for this morphology to avoid misclassification. Due to the rarity of cases, optimal treatment at this site has not been established.

Sebaceous carcinoma in solid organ transplant recipients: The elegant path from epidemiology to etiology

Sebaceous carcinoma (SC) is a rare skin cancer associated with rapid progression and relatively poor survival, particularly in solid organ transplant recipients (SOTRs). Immunosuppressive regimens place SOTRs at substantially increased risk of a variety of skin cancers; recent research has shown a 25-fold increase in SC in the SOTR population, especially among lung recipients, older males, those with longer time since transplant, and patients undergoing induction therapy with thymoglobulin. The potential etiologic mechanisms underlying SC are multifaceted and complex. Immunosuppression creates a microcosm through which to view causative factors for carcinogenesis which has implications in elucidating mechanistic etiologies for SC far beyond the SOTR population, since not all cancers are more common in immunosuppressed patients. Research integrating the role of oncogenic viruses, underlying medical conditions, genetic risk factors, toxicity of prophylactic medications, drug-induced photosensitization, and T-cell deficiency/dysfunction is needed to better elucidate the factors underlying SC in immunosuppressed hosts. In this report, we integrate current research regarding SC in SOTR patients using the causal pie/sufficient-component cause model. In doing so, we provide a paradigm through which to view future research regarding the etiology of SC.

Enhanced Spontaneous Skin Tumorigenesis and Aberrant Inflammatory Response to UVB Exposure in Immunosuppressed Human Papillomavirus Type 8‒Transgenic Mice

Human papillomaviruses (HPVs) from the beta genus are commensal viruses of the skin usually associated with asymptomatic infection in the general population. However, in individuals with specific genetic backgrounds, such as patients with epidermodysplasia verruciformis, or those with immune defects, such as organ transplant recipients, they are functionally involved in sunlight-induced skin cancer development, mainly keratinocyte carcinoma. Despite their well-established protumorigenic role, the cooperation between β-HPV infection, impaired host immunosurveillance, and UVB exposure has never been formally shown in animal models. In this study, by crossing skin-specific HPV8-transgenic mice with Rag2-deficient mice, we have generated a preclinical mouse model, named Rag2^‒/‒:K14-HPV8. These mice display an unhealthy skin phenotype and spontaneously develop papilloma-like lesions spreading to the entire skin much more rapidly compared with Rag2^+/+:K14-HPV8 mice. Exposure to low doses of UVB radiation is sufficient to trigger severe skin inflammation in Rag2^‒/‒:K14-HPV8 but not in Rag2^+/+:K14-HPV8 mice. Their inflamed skin very much resembled that observed in cutaneous field cancerization in organ transplant recipients, showing high levels of UVB-damaged cells, enhanced production of proinflammatory cytokines, and mast cell recruitment to the dermis. Overall, this immunocompromised HPV8-transgenic mouse model shows that the coexistence of immune defects, β-HPV, and UVB exposure promotes skin cancer development.

Spectrum of Nonkeratinocyte Skin Cancer Risk Among Solid Organ Transplant Recipients in the US

Importance

Nonkeratinocyte skin cancers are an important cause of morbidity and mortality for immunosuppressed solid organ transplant recipients (SOTRs), but the spectrum of disease and risk factor characteristics are unknown.

Objective

To characterize the spectrum of disease and risk factors for common and rare nonkeratinocyte skin cancers in SOTRs.

Design, Setting, and Participants

This population-based cohort study included 444 497 SOTRs who underwent a transplant in the US between January 1, 1987, and December 31, 2017, using linked data from the national transplant registry and 32 cancer registries. Data analysis was conducted from April 1, 2021, to September 30, 2021.

Main Outcomes and Measures

Standardized incidence ratios (SIRs) were used to assess risk relative to the general population, and Poisson regression was used to evaluate risk factors.

Results

A total of 2380 nonkeratinocyte skin cancers were identified among 444 497 SOTRs (median age at transplant, 50 years; range, 0-96 years; 274 276 [61.7%] male; 272 241 [61.2%] non-Hispanic White). Melanoma was the most common cancer (1471 [61.8%]), followed by Merkel cell carcinoma (334 [14.0%]), Kaposi sarcoma (186 [7.8%]), sebaceous carcinoma (170 [7.1%]), and cutaneous lymphomas (108 [4.5%]). Risks were most strongly elevated for cancers associated with viruses, including Kaposi sarcoma (SIR, 20.5; 95% CI, 17.7-23.7), Merkel cell carcinoma (SIR, 16.2; 95% CI, 14.5-18.1), and extranodal natural killer/T-cell lymphoma (SIR, 44.3; 95% CI, 5.37-160). Risks were also significantly elevated for sebaceous carcinoma (SIR, 15.2; 95% CI, 13.0-17.7), anaplastic large cell lymphoma (SIR, 6.82; 95% CI, 4.53-9.85), and diffuse large B-cell lymphoma (SIR, 5.17; 95% CI, 3.28-7.76). Several characteristics were independently associated with greater risk for multiple skin cancer types, including male sex, older age at transplant, factors associated with UV radiation exposure (non-Hispanic White race and ethnicity, living in an area with higher UV radiation exposure, and posttransplant diagnosis of keratinocyte carcinoma), and increasing time since transplantation. Treatment with mammalian target of rapamycin inhibitors was associated with reduced melanoma incidence (incidence rate ratio, 0.75; 95% CI, 0.57-0.98). A total of 847 skin cancers (39.4%) occurred on the head and neck.

Conclusions and Relevance

The findings of this cohort study suggest that viruses, UV radiation exposure, and immunosuppression are associated with the development of skin cancer in SOTRs. Certain high-risk subgroups may benefit from increased skin surveillance, and treatment with mammalian target of rapamycin inhibitors could be effective for melanoma chemoprevention in the transplant population.

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.

Hughes flap in the management of lower lid retraction

PURPOSE

We present a retrospective case series on the use of Hughes flap in managing acquired cicatricial lower lid retraction.

METHODS

This was a multicentre, retrospective case series. Data was collected from medical records across different sites within Australia (Adelaide, Melbourne, and Sydney) and New Zealand (Hamilton).

RESULTS

Fourteen patients were identified. The aetiology of cicatricial lower lid retraction included previous lid lesion excision and reconstruction, eyelid trauma, orbital fracture repair, orbital radiotherapy, and lateral canthal dystopia from previous lid surgeries. 4/14 (29%) cases had undergone other surgery to correct the retraction prior to the Hughes flap. Pre-operative lagophthalmos due to lower lid retraction was noted in 11/14 (79%) cases with a median 2 mm (range: 1-5 mm). Exposure keratopathy was present in 7/14 (50%) cases. There were no peri-operative complications during Hughes flap reconstruction. One patient had post-operative upper eyelid retraction that did not require any further intervention. One patient had persistent lagophthalmos and exposure keratopathy that is being managed conservatively. One patient had wound dehiscence and further lid retraction following flap division, which required further surgery. Median length of follow-up was 15 months (range: 0.5-84 months). At final review, improvement or resolution of symptoms was seen in 13/14 (93%) cases.

CONCLUSIONS

A Hughes flap is an effective surgical technique for the management of cicatricial lower lid retraction.

MicroRNA-3907 promotes the proliferation and migration of sebaceous gland carcinoma of the eyelid by targeting thrombospondin 1

MicroRNAs (miRNAs/miRs) play an important role in various types of carcinoma, including sebaceous gland carcinoma (SGC) of the eyelid. miR-3907 was found to be highly expressed in lung cancer; however, to the best of our knowledge, the biological role of miR-3907 in SGC has not previously been evaluated. The aim of the present study was to determine the role and mechanism of miR-3907 in the occurrence and development of SGC. miR-3907 was screened and identified as a novel upregulated miRNA in SGC tissues and cells, as determined using miRNA microarrays and reverse transcription-quantitative (RT-q) PCR analyses. Compared with the control group, cellular proliferation and migration were enhanced in the miR-3907 mimics group, and decreased in the miR-3907 inhibitor group. Moreover, miR-3907 negatively regulated thrombospondin 1 (THBS1) expression, as shown by bioinformatics prediction, RT-qPCR, western blotting and dual-luciferase reporter assays. In addition, compared with the control group, the small interfering (si) siRNA-THBS1 group exhibited enhanced proliferation and migration abilities, which were decreased in the THBS1 overexpression group. Furthermore, THBS1 overexpression was found to attenuate the stimulative effect of miR-3907 mimics, and THBS1-knockdown reversed the inhibitory effect of the miR-3907 inhibitor in SGC cells. Collectively, the results of the present study indicated that miR-3907 promoted the proliferation and migration of SGC by downregulating THBS1, and that this axis may be a potential target for the prognostic assessment and treatment of SGC.

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.

Human Papillomavirus Related Neoplasia of the Ocular Adnexa

Human papillomaviruses (HPV) are a large group of DNA viruses that infect the basal cells of the stratified epithelium at different anatomic locations. In the ocular adnexal region, the mucosa of the conjunctiva and the lacrimal drainage system, as well as the eyelid skin, are potential locations for HPV-related neoplasia. The role of HPV in squamous cell neoplasia of the ocular adnexa has been debated for several decades. Due to the rarity of all these tumors, large studies are not available in the scientific literature, thereby hampering the precision of the HPV prevalence estimates and the ability to conclude. Nevertheless, increasing evidence supports that defined subsets of conjunctival papillomas, intraepithelial neoplasia, and carcinomas develop in an HPV-dependent pathway. The role of HPV in squamous cell tumors arising in the lacrimal drainage system and the eyelid is still uncertain. Further, the potential of HPV status as a diagnostic, prognostic, or predictive biomarker in these diseases is a topic for future research.

PD-L1 expression in sebaceous carcinomas

BACKGROUND

Traditional systemic treatments for unresectable, recurrent, and/or advanced sebaceous carcinoma (SC) are ineffective. Tumoral immune microenvironment characterization is essential for considering immune checkpoint inhibitors as a treatment option.

METHODS

A total of 173 resected SCs were reviewed. Clinical information, lesion size, and location were collected. Microscopic examination documented histopathologic features and expression of immunohistochemical markers PD-L1 and CD8. PD-L1 percentage was assessed amongst tumor (PD-L1 + Tu) and immune infiltrating cells (PD-L1 + Inf). Each case was attributed a combined positive score (CPS) following Head and Neck squamous cell carcinoma recommendations. PD-L1 expression was evaluated according to clinicopathologic parameters. Human Papilloma Virus presence (HPV) was analyzed using PCR microarray scanning.

RESULTS

A therapeutically relevant CPS was seen in 51.4% of cases. Higher PD-L1 + Tu, PD-L1 + Inf, and CPSs were positively associated with greater lesion size and an extraocular location. No association was seen with patient age or gender. 9.2% of SCs showed PD-L1 + Tu ≥ 1, while 52.0% showed PD-L1 + Inf ≥ 1. A higher CD8 + T-lymphocyte density was significantly associated with a higher CPS, PD-L1 + Tu, and PD-L1 + Inf. Tumor-associated T-cell infiltrate's density was higher along tumor periphery. HPV-16, HPV-43, HPV-52, and HPV-66 were detected in 8.4% of SCs. There was no significant association between HPV status, PD-L1 expression, and CPS. A significant number of SCs express PD-L1 at therapeutic levels. Nevertheless, PD-L1 expression shows a higher intertumoral heterogeneity, in extraocular than in biologically distinct periocular cases.

CONCLUSION

Our data support the need for large-scale prospective studies evaluating anti-PD-L1 immunotherapy mainly in extraocular SC treatment.

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.

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.

Ocular Adnexal Adenomatoid Sebaceous Gland Hyperplasia: A Clinical and Immunopathologic Analysis in Relation to the Muir-Torre Syndrome

The purpose of this study is to codify the microscopic diagnostic criteria for ocular adnexal brow and caruncular sebaceous gland hyperplasias (pseudoadenomatoid) that distinguish it from an adenoma. Clinical records and photographs were critically reviewed and microscopic slides were stained with hematoxylin and eosin and immunochemically stained for adipophilin, androgen receptor, p16, p53, a spectrum of cytokeratins, Ki-67 and mismatch repair nuclear protein expression for MLH1, MSH2, PMS2, and MSH6. The patients and their close relatives had no history of cancer. Cytokeratin 7 and especially cytokeratin 17 highlighted the presence of ducts in the hyperplastic lesion, which are not present in adenomas. p16 and p53 were negative and Ki-67 immunostaining demonstrated similar low proliferation indices for normal and hyperplastic glands. The mismatch repair nuclear protein expressions were preserved in both lesions. Histopathologic misdiagnosis of adenomatoid sebaceous gland hyperplasia as an adenoma can lead to the impression of an association with the Muir-Torre syndrome. Cytokeratins 7 and 17 immunostaining can be helpful in highlighting compressed ducts that in exuberant sebaceous gland hyperplasias may lead to a diagnosis of an adenoma (in which ducts are absent). Negative immunostaining for p16 rules out a possible etiologic role of human papillomavirus in hyperplasias and the negative p53 staining indicates the lesions are not truly neoplastic. The preservation of mismatch repair nuclear protein expression rules out the likelihood of the Muir-Torre syndrome. The current cases convincingly establish that sebaceous hyperplasia is not associated with the Muir-Torre syndrome by both clinical findings and immunohistochemical testing.Two yellow lesions, from the brow and caruncle, were examined microscopically and immunohistochemically to establish the diagnosis of sebaceous gland hyperplasia and to rule out the Muir-Torre syndrome.

Risk of Rare Cancers Among Solid Organ Transplant Recipients

BACKGROUND

Immunosuppressed solid organ transplant recipients (SOTRs) have elevated rates of certain rare cancers caused by viruses. Evaluating risk of rare cancers among SOTRs may provide etiological clues for additional cancers linked to poor immunity and viral infections.

METHODS

We performed a cohort study of 262 455 SOTRs (1987-2014) from the US SOTR registry linked to 17 population-based cancer registries. First cancers in SOTRs were categorized using an established classification scheme based on site and histology. Standardized incidence ratios (SIRs) compared risk in SOTRs with the general population. We used Poisson regression to calculate incidence rate ratios according to immune-related SOTR characteristics, including time since transplant (ie, duration of immunosuppression). All statistical tests were 2-sided.

RESULTS

We examined 694 distinct cancer subtypes, with 33 manifesting statistically significantly elevated SIRs (Bonferroni P < 7.2 × 10-5). All 33 are rare (incidence <6 per 100 000 person-years) and several have known viral etiology (eg, Merkel cell carcinoma: SIR = 24.7, 95% confidence interval [CI] = 20.8 to 29.1). Additional cancers that were increased include squamous cell carcinomas of the lip (SIR range = 18.3-19.8), eye and adnexa (SIR = 13.8, 95% CI = 7.9 to 22.3), salivary gland (SIR = 9.3, 95% CI = 6.1 to 13.5), and nasal cavity and sinuses (SIR = 4.5, 95% CI = 2.8 to 6.8); sebaceous adenocarcinoma (SIR = 34.3, 95% CI = 26.3 to 44.0); malignant fibrous histiocytoma (15.4); and subtypes of bladder, kidney, lung, and colon cancer (SIR range = 3.2-13.3). Incidence of several cancers increased over time since transplant (Ptrend < .05), including squamous cell carcinomas of the lip, salivary gland, and anogenital sites.

CONCLUSIONS

SOTRs experience elevated rates of several rare cancers. Because some of these cancers exhibit aggressive behavior with poor outcomes, it is important to further characterize the role of immunity and the potential involvement of oncogenic viruses to improve prevention and treatment.

Sebaceous Carcinoma Incidence and Survival Among Solid Organ Transplant Recipients in the United States, 1987-2017

Importance

Risk of sebaceous carcinoma (SC), a rare skin cancer associated with Muir-Torre syndrome, is elevated among solid organ transplant recipients (SOTRs). However, population studies evaluating this association and assessing survival for posttransplant cases are lacking, and further understanding of SC epidemiology in this immunosuppressed population could provide etiologic and clinical insights.

Objective

To assess SC incidence and patient survival after solid organ transplantation.

Design, Setting, and Participants

This cohort study, conducted from January 1, 1987, to December 31, 2017, used data from the Transplant Cancer Match Study, which links transplant and cancer registry data for 17 states and 1 metropolitan area in the United States. Altogether, these registries account for approximately 46% of all US transplants. Data on demographic and transplant characteristics as well as induction and initial maintenance immunosuppressive therapies were obtained from the transplant registry. Standardized incidence ratios (SIRs) comparing SC incidence among SOTRs to the general population were calculated. Incidence rate ratios (IRRs) comparing SC risk between SOTR subgroups were calculated using multivariate Poisson regression. Cox regression was used to compare overall survival between SC cases in SOTRs and other individuals.

Main Outcomes and Measures

Sebaceous carcinoma incidence and overall patient survival after transplantation compared with the general population.

Results

A total of 326 282 transplant procedures were performed for 301 075 patients (No. [%] age at transplant, 126 550 [38.8%] aged 0-44 years; 82 394 [25.3%] aged 45-54 years; 82 082 [25.5%] aged 55-64 years; 35 256 [10.8%] aged ≥65 years; 201 354 male patients [61.7%]; 202 557 White patients [62.1%]). A total of 102 SCs were diagnosed in 301 075 SOTRs, corresponding to a 25-fold increased incidence (SIR, 24.8; 95% CI, 20.2-30.1). Incidence was especially elevated among lung recipients (SIR, 47.7; 95% CI, 20.6-94.0) and after a posttransplant diagnosis of cutaneous squamous cell carcinoma (SIR, 104.0; 95% CI, 62.8-163.0). Among SOTRs, factors independently associated with SC risk included male sex (IRR, 2.46; 95% CI, 1.48-4.07; P < .001), race/ethnicity (non-Hispanic Black vs non-Hispanic White, IRR, 0.28; 95% CI, 0.10-0.77; P = .01), older age (IRR, 7.85; 95% CI, 3.85-16.0; ≥65 vs 0-44 years; P < .001 for trend), use of thymoglobulin induction (IRR, 1.82; 95% CI, 1.16-2.86; P = .009), posttransplant cutaneous squamous cell carcinoma (IRR, 4.60; 95% CI, 2.67-7.94; P < .001), and longer time since transplant (IRR, 8.40; 95% CI, 3.94-17.90; ≥10 vs 0-1.9 years; P < .001 for trend). Muir-Torre syndrome-associated cancers were rare among both SOTRs and others with SC (3.3%-4.1%). Among patients with SC, prior transplantation was associated with increased overall mortality (adjusted hazard ratio, 2.09; 95% CI, 1.45-3.01), although few deaths were attributed to SC (4 of 92 SOTRs [4.3%]; 235 of 3585 non-SOTRs [6.6%]).

Conclusions and Relevance

Among SOTRs, results of this large cohort study suggest that SC was associated with measures of immunosuppression, and overall survival was worse than for other patients with SC. Findings also suggest a possible role for UV radiation in carcinogenesis.

Sebaceous Carcinoma Epidemiology and Genetics: Emerging Concepts and Clinical Implications for Screening, Prevention, and Treatment

Sebaceous carcinoma is an aggressive skin cancer with a 5-year overall survival rate of 78% for localized/regional disease and 50% for metastatic disease. The incidence of this cancer has been increasing in the United States for several decades, but the underlying reasons for this increase are unclear. In this article, we review the epidemiology and genetics of sebaceous carcinoma, including recent population data and tumor genomic analyses that provide new insights into underlying tumor biology. We further discuss emerging evidence of a possible viral etiology for this cancer. Finally, we review the clinical implications of recent advances in sebaceous carcinoma research for screening, prevention, and treatment.

Whole-exome sequencing for ocular adnexal sebaceous carcinoma suggests PCDH15 as a novel mutation associated with metastasis

Ocular adnexal sebaceous carcinoma (OASeC) is an aggressive eyelid carcinoma. Analysis of molecular-genetic drivers of this disease could reveal new prognostic markers and actionable targets for treatment. To identify somatically acquired genomic mutations in OASeC and explore their associations with metastasis, whole-exome sequencing on DNA extracted from retrospectively collected tumor samples was performed. Thirty-one patients in two orbital oncology centers with OASeC were included. Sequencing results were analyzed to detect mutations and explore their possible association with metastasis. The median patient age was 64 years. A total of 1780 candidate somatic mutations were identified with median mutation rate of 1.0/Mb (range, 0.2-13.6). The five most commonly mutated genes (as determined by MutSig; q value < 0.25) were TP53 (mutated in 22 cases), ZNF750 (13 cases), RB1 (12 cases), NOTCH1 (8 cases), and PCDH15 (5 cases). Mutations in ZNF750 or NOTCH1 pathway genes were present in 24 (77%) of the 31 cases; there was a trend toward mutual exclusivity of ZNF750 and NOTCH1 mutations. All eight tumors with NOTCH1 mutations also had TP53 and/or RB1 mutations. Four of the five PCDH15 mutations and all four PCDH15 missense mutations were identified in patients with metastatic disease, including one patient with distant metastasis and three with nodal metastasis. PCDH15 was significantly associated with metastasis (P = 0.01). We identified the most commonly mutated genes in a series of OASeCs and found a previously unreported mutation in OASeC, PCDH15 mutation, that was significantly associated with metastasis. NOTCH1 mutation is an actionable mutation; clinical trials targeting this mutation are available throughout the US and could be considered for patients with metastatic NOTCH1-mutant OASeC. TP53, ZNF750, RB1, and PCDH15 mutations are most likely loss-of-function mutations and may have diagnostic and prognostic importance.

Update on the pathology, genetics and somatic landscape of sebaceous tumours

Cutaneous sebaceous neoplasms show a predilection for the head and neck area of adults and include tumours with benign behaviour, sebaceous adenoma and sebaceoma, and sebaceous carcinoma with potential for an aggressive disease course at the malignant end of the spectrum. The majority of tumours are solitary and sporadic, but a subset of tumours may be associated with Lynch syndrome, also known as hereditary non-polyposis colon cancer (HNPCC) and previously referred to as Muir-Torre syndrome (now known to be part of Lynch syndrome). This review provides an overview of the clinical and histological features of cutaneous sebaceous neoplasia with an emphasis on differentiating features and differential diagnosis. It also offers insights into the recently described molecular pathways involved in the development of sebaceous tumours and their association with Lynch syndrome.

Villous Sebaceous Adenoma Arising from the Caruncular Surface Squamous Epithelium

A 68-year-old woman developed an asymptomatic left caruncular multilobular lesion over one year. Excision of the lesion displayed a benign sebaceous neoplasm taking origin from the surface squamous epithelium which invaginated into the stroma to create crypts resembling the conjunctival pseudoglands of Henle or the glands of Lieberkuhn of the small intestine. Scattered sebaceous cells were also discovered in the surface squamous epithelium. The cryptal walls spawned lateral sebaceous gland lobules that were adipophilin positive. p16 was positive in the surface epithelium, the cryptal walls, and in the basal cells of the sebaceous lobules. No defects in nuclear mismatch repair protein expression were identified, which together with the absence of a familial cancer history, rendered unlikely an association with the Muir-Torre syndrome.

The role of infectious agents in cancer of the ocular region

The purpose of the study was to investigate the association between infectious agents and the development of cancer in the ocular adnexa. A comprehensive literary study was carried out, reviewing and summarizing previous reports on the topic. A broad range of malignancies of the ocular adnexa are associated with infectious agents. A strong association and possible causal relationship between the infectious agent and the development of ocular adnexal cancer are seen in Merkel cell carcinoma (Merkel cell polyomavirus), Burkitt lymphoma (Epstein-Barr virus) and Kaposi sarcoma (human herpesvirus 8). Infection with Chlamydia psittaci has been associated with the development of extranodal marginal zone B-cell lymphoma in Italy. Human papillomavirus infection has been associated with the development of squamous cell carcinomas of the ocular adnexa, although with a highly variable reported prevalence. By exploring the role of infectious agents in the ocular adnexa and the mechanism by which they contribute to oncogenesis, the diagnostics, management and prevention of these malignancies may also improve. Antibiotic treatment and vaccines against infectious agents may be valuable in future treatment. Additionally, the presence of infectious agents within the tumours may have a prognostic or predictive value.

Cutaneous sebaceous carcinoma

Cutaneous sebaceous carcinoma occurs almost exclusively on the head and neck and has a significant propensity for recurrence and metastasis. It is easily mistaken for benign conditions, resulting in inappropriate management. Thus, it is important to maintain a high index of suspicion. Despite previous reports, sebaceous carcinoma may occur with similar frequency in Asians and whites. Recent genetic data suggest there are multiple mutational groups of sebaceous carcinoma, paving the way for targeted treatment. After a diagnosis, investigations for staging and for Muir-Torre syndrome should be considered. The available evidence on the treatment options for sebaceous carcinoma is discussed, and specific recommendations for management are made.

Intraductal sebaceous papilloma of a meibomian gland: a new entity possibly associated with the MSH6 subtype of the Muir-Torre syndrome

Over several months, a painless, multinodular, non-erythematous swelling of the deep tissues of his left upper eyelid developed in a 63-year-old man. An excisional biopsy with histopathologic evaluation disclosed a unique sebaceous papilloma within a cyst lined by non-keratinizing squamous epithelium that focally displayed a variably thick, superficial, eosinophilic cuticular layer. Immunohistochemical staining demonstrated that the tumor and its epithelial cystic lining had a profile consistent with Meibomian gland duct epithelium. Adipophilin highlighted cytoplasmic vacuolar lipid positivity. The encapsulation of the lesion, absence of nuclear atypia, and Ki-67 nuclear positivity restricted to the basilar cells established its intrinsically benign nature. The patient's clinical history was remarkable for pulmonary and colonic carcinomas resected, respectively, 20 years and 8 years earlier. DNA mismatch repair protein expression studies disclosed loss of nuclear immunostaining of MSH6 protein, pointing to the possibility of an underlying rare MSH6 variant of the Muir-Torre syndrome, not yet described in the ophthalmic literature. p16 nuclear positivity was also found in the tumor cells, indicating the possible role of high-risk human papillomavirus as an additional factor in the genesis of the tumor. Genetic evaluation of normal and tumoral tissues in future similar cases will detect if there is an underlying germline mutation versus a somatic mutation limited to the tumor. This will be required to fully establish a predictable linkage with this new subtype of the Muir-Torre syndrome.

The color of skin: yellow diseases of the skin, nails, and mucosa

The colors reflected from the skin are important indicators of dermatologic and systemic disorders. Incident light is subject to absorption by chromophores in the skin and scattering. Chromophores associated with yellow light reflection include the carotenoids and bilirubin. Various pathophysiologic mechanisms associated with these and other chromophores manifest with a yellow hue on examination. This review describes these mechanisms and the clinical features of yellow skin disorders by morphology. A brief summary of the differential diagnosis, laboratory investigations, and treatments are presented. Yellow skin disorders are a heterogenous group composed of abnormalities in keratin, elastic and connective tissue, lipid metabolism, and other states of metabolic, inflammatory, or organ dysfunction. Patients will present through different routes, and skin disease may precede or follow systemic disease. Dermatologists have an essential role in identifying those with malignant or systemic associations to ensure early diagnosis and treatment.

Loss of ZNF750 in ocular and cutaneous sebaceous carcinoma

BACKGROUND

Sebaceous carcinoma (SeC) is an uncommon malignancy arising from sebaceous glands of the conjunctiva and skin. Recurrent mutations in the ZNF750 were recently identified in ocular SeC. We assessed whether ZNF750 loss is a specific feature of ocular SeC or a general feature of sebaceous tumors.

METHODS

Immunostaining for ZNF750 expression was performed in 54 benign and malignant sebocytic proliferations. Staining for ZNF750 was scored on a three-tier scale: positive (>75%), partially positive (5%-74%), and negative (<5%).

RESULTS

ZNF750 expression was negative in 4/11 ocular SeC, and partially positive in 4/11 ocular SeC and 6/13 cutaneous SeC. No extraocular tumors were negative. No loss was found in sebaceous adenoma or sebaceous hyperplasia. In nine previously sequenced ocular SeCs, two lacked detectable somatic mutations in ZNF750, but showed complete loss of staining, indicating non-mutational inactivation of ZNF750.

CONCLUSION

We show complete loss of the ZNF750 epidermal differentiation regulator in about half of ocular SeC, highlighting the most common genetic defect in this cancer type. Loss of ZNF750 expression is seen even in tumors without truncating mutations and reduced in many of the remaining ocular and cutaneous SeC. In contrast, no ZNF750 loss was detected in benign sebaceous proliferations.