Diagnostic utility of adipophilin immunostain in periocular carcinomas

Lipid droplets provide metabolic flexibility for cancer progression

A hallmark of cancer cells is their remarkable ability to efficiently adapt to favorable and hostile environments. Due to a unique metabolic flexibility, tumor cells can grow even in the absence of extracellular nutrients or in stressful scenarios. To achieve this, cancer cells need large amounts of lipids to build membranes, synthesize lipid-derived molecules, and generate metabolic energy in the absence of other nutrients. Tumor cells potentiate strategies to obtain lipids from other cells, metabolic pathways to synthesize new lipids, and mechanisms for efficient storage, mobilization, and utilization of these lipids. Lipid droplets (LDs) are the organelles that collect and supply lipids in eukaryotes and it is increasingly recognized that the accumulation of LDs is a new hallmark of cancer cells. Furthermore, an active role of LD proteins in processes underlying tumorigenesis has been proposed. Here, by focusing on three major classes of LD-resident proteins (perilipins, lipases, and acyl-CoA synthetases), we provide an overview of the contribution of LDs to cancer progression and discuss the role of LD proteins during the proliferation, invasion, metastasis, apoptosis, and stemness of cancer cells.

Adipophilin: roles in physiology and pathology

Adipophilin (ADRP/ADPH/PLIN2), an adipocyte differentiation-related protein, is highly expressed at a very early time during the differentiation of adipocytes. It assists in the formation and maintenance of intracellular lipid droplets and plays a role in regulating the physiological functions of the body. More and more studies indicate that it is involved in the occurrence and development of a variety of glycolipid metabolic diseases and tumours. In this review, we comprehensively stated the expression and functions of adipophilin and introduced its roles in physiology and pathology.

Metabolic alterations in carcinoma ex pleomorphic adenoma development of lacrimal glands

PURPOSE

To evaluate metabolic alterations along with the carcinoma ex pleomorphic adneoma (CXPA) development of lacrimal glands (LG).

METHODS

Four samples of the normal LG (NLG), 9 of pleomorphic adenoma (PA), 4 of residual PA (rPA), and 4 of CXPA of LG were included. GLUT-1, HIF-1α, FASN, and adipophilin by immunohistochemical stains were performed in the selected cases.

RESULTS

Was observed higher expression of markers associated with glycolytic and lipid metabolism in the tumor tissue samples when compared to the NLG samples. Additionally, GLUT-1, FASN, and Adipophilin were more expressed in CXPA samples while HIF-1α in PA samples.

CONCLUSIONS

In conclusion, our results demonstrate overexpression of FASN and Adipophilin in CXPA which may reflect a metabolic shift toward lipogenesis in cancer cells.

Lipid Droplet Accumulation Independently Predicts Poor Clinical Prognosis in High-Grade Serous Ovarian Carcinoma

Simple Summary

High-grade serous carcinoma (HGSOC) is the most aggressive subtype of ovarian cancer and accounts for the vast majority of advanced stage cases. Intracellular accumulation of lipids as lipid droplets has been recognized as one of the characteristics of cancers and implicated in poor prognosis of several cancers, such as human melanomas. Here, we investigated the relationship between prognosis and lipid accumulation in HGSOC, and found that enhanced lipid accumulation in HGSOC tissues significantly correlated with poor prognosis. In cell-based assays with human ovarian cancer cells, we provide evidence that aerobic glycolysis, which is one of the characteristic metabolic abnormalities in cancer, induced lipid accumulation within cancer cells and targeting the lipid accumulation could suppress cancer cell proliferation. Thus, our results propose abnormal lipid accumulation as a negative indicator of HGSOC prognosis and a novel therapeutic target.

Abstract

High-grade serous ovarian carcinoma (HGSOC) is an epithelial cancer that accounts for most ovarian cancer deaths. Metabolic abnormalities such as extensive aerobic glycolysis and aberrant lipid metabolism are well-known characteristics of cancer cells. Indeed, accumulation of lipid droplets (LDs) in certain types of malignant tumors has been known for more than 50 years. Here, we investigated the correlation between LD accumulation and clinical prognosis. In 96 HGSOC patients, we found that high expression of the LD marker adipophilin was associated with poor progression-free and overall survival (p = 0.0022 and p = 0.014, respectively). OVCAR-3 ovarian carcinoma cells accumulated LDs in a glucose-dependent manner, which suggested the involvement of aerobic glycolysis and subsequently enhanced lipogenesis, with a result being LD accumulation. The acyl-CoA: cholesterol acyltransferase 1 inhibitor K604 and the hydroxymethylglutaryl-CoA reductase inhibitor pitavastatin blocked LD accumulation in OVCAR-3 cells and reduced phosphorylation of the survival-related kinases Akt and ERK1/2, both of which have been implicated in malignancy. Our cell-based assays thus suggested that enhanced aerobic glycolysis resulted in LD accumulation and activation of survival-related kinases. Overall, our results support the idea that cancers with lipogenic phenotypes are associated with poor clinical prognosis, and we suggest that adipophilin may serve as an independent indicator of a poor prognosis in HGSOC.

Comparison of adipophilin and recently introduced PReferentially expressed Antigen in MElanoma immunohistochemistry in the assessment of sebaceous neoplasms: A pilot study

BACKGROUND

We and others have noticed consistent staining of sebaceous glands with PReferentially expressed Antigen in MElanoma (PRAME). We aimed to determine whether PRAME was as sensitive, specific, and interpretable as adipophilin for distinguishing sebaceous neoplasms (SNs) from other neoplasms.

METHODS

Twenty SNs and 32 control cases were stained for PRAME and adipophilin. Extent of staining was scored as follows: 0, no staining; 1, <5% positivity; 2, 5% to 50% positivity; and 3, >50% positivity. Intensity was scored as negative, weak, moderate, or strong. A composite score was determined by adding the scores for extent and intensity.

RESULTS

PRAME had positive composite scores in all 20 SNs in the more differentiated areas, whereas adipophilin had positive composite scores in 19/20 cases. PRAME showed positivity in the basaloid cells in 15/16 cases, whereas adipophilin was positive in 14. Among controls, PRAME and adipophilin had positive composite scores in 3/32 cases and 6/32 cases, respectively.

CONCLUSIONS

PRAME and adipophilin are comparable in terms of distribution and intensity for staining sebocytes. In the basaloid cells, PRAME expression is often more diffuse and easier to detect than adipophilin. In comparing the SNs to the controls, PRAME was more sensitive and more specific than adipophilin. PRAME could be used as an additional marker of sebaceous differentiation in everyday practice.

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.

Bioinformatics analysis of the microRNA-mRNA network in sebaceous gland carcinoma of the eyelid

Sebaceous gland carcinoma (SGC) of the eyelid is an uncommon aggressive tumor with a relatively high rate of local recurrence and a poor prognosis following metastasis. However, the molecular mechanisms underlying the pathogenesis of SGC remain unclear. The purpose of the present study was to clarify microRNA (miRNA) expression profiles in SGC and to explore novel miRNA-mRNA networks of SGC. A small RNA-sequencing analysis was performed to identify miRNAs differentially expressed between SGC and sebaceous adenoma control samples. Bioinformatics analyses were conducted to reveal biological functions, canonical pathways and molecular interaction networks using integrated miRNA-mRNA datasets, including mRNA expression profiles of SGC from our previous study. The present results demonstrated that 16 upregulated miRNAs and 516 downregulated mRNAs were associated with loss of lipid metabolism function and enriched in cholesterol biosynthesis pathways. By contrast, 29 downregulated miRNAs and 194 upregulated mRNAs were mainly associated with the promotion of cell survival and proliferation in addition to enrichment of DNA damage-induced cell cycle-regulation pathways. Furthermore, network analyses revealed that the upregulated miRNAs, miR-130a-3p and miR-939-5p, and the downregulated miRNAs, miR-146a-5p, miR-149-3p, miR-193a-3p, miR-195-5p and miR-4671-3p, could be upstream regulators related to these functional changes of SGC. These results improved the understanding of molecular mechanisms of SGC and may help to improve the diagnosis of SGC.

Adipophilin expression in cutaneous malignant melanoma is associated with high proliferation and poor clinical prognosis

Adipophilin (ADP) is a primary protein component of lipid droplets (LDs). For more than half a century, certain types of cancer cells have been known to contain LDs in their cytoplasm. However, the pathological significance of ADP or LDs in cancer remains unclear. In the present study, we investigated the association between ADP and other pathological characteristics in cutaneous malignant melanomas to clarify the role of ADP in melanoma cells. We immunostained whole paraffin sections of primary cutaneous melanomas obtained from 90 cases for ADP, after which we analyzed the correlation between ADP immunohistochemistry (IHC) and patient survival data. We also studied the relationship between the ADP IHC score and in situ hybridization (ISH) score of ADP mRNA, and the Ki67-labeling index (Ki67-LI) by using tissue microarrays consisting of 74 primary cutaneous malignant melanomas, 19 metastasizing melanomas, and 29 melanocytic nevi. Finally, we analyzed the relationship between ADP expression and cell proliferation in cutaneous melanoma cell lines. We found that high ADP expression was associated with poor metastasis-free survival, disease-specific survival, and overall survival rates of patients with cutaneous melanomas (P < 0.05). By linear regression analysis, ADP IHC was correlated with increasing ADP mRNA ISH H-scores and Ki67-LI scores in melanocytic lesions (P < 0.01). ADP IHC and ADP ISH H-scores and Ki67-LI scores were greater in pT3-4 melanomas than in pT1-2 melanomas. In cell-based assays, cells with increased ADP expression showed higher proliferation rates compared with those of low-ADP cells. Thus, ADP expression in malignant melanoma was significantly associated with high cell proliferation and poor clinical prognosis. Our results thus indicate a significant association between ADP and melanoma progression, and we propose that ADP may be a novel marker of aggressive cutaneous melanoma with a lipogenic phenotype.

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.

Lipid droplets: platforms with multiple functions in cancer hallmarks

Lipid droplets (also known as lipid bodies) are lipid-rich, cytoplasmic organelles that play important roles in cell signaling, lipid metabolism, membrane trafficking, and the production of inflammatory mediators. Lipid droplet biogenesis is a regulated process, and accumulation of these organelles within leukocytes, epithelial cells, hepatocytes, and other nonadipocyte cells is a frequently observed phenotype in several physiologic or pathogenic situations and is thoroughly described during inflammatory conditions. Moreover, in recent years, several studies have described an increase in intracellular lipid accumulation in different neoplastic processes, although it is not clear whether lipid droplet accumulation is directly involved in the establishment of these different types of malignancies. This review discusses current evidence related to the biogenesis, composition and functions of lipid droplets related to the hallmarks of cancer: inflammation, cell metabolism, increased proliferation, escape from cell death, and hypoxia. Moreover, the potential of lipid droplets as markers of disease and targets for novel anti-inflammatory and antineoplastic therapies will be discussed.

Sebaceoma of a Meibomian Gland of the Upper Eyelid

Over a period of 1 year, a 74-year-old man slowly developed a painless left upper eyelid intratarsal mass. The skin was movable over the lesion. At surgery, a well-circumscribed, yellow-white, partially cystic tumor was encountered. Histopathologically it was composed of a random mixture of basaloid and sebaceous cells arranged in interconnecting cords. Immunohistochemical evaluation disclosed epithelial membrane antigen, adipophilin, and cytokeratin 14 positivity. These findings led to the diagnosis of a sebaceoma. The tumor cells abnormally failed to express mismatch repair proteins for MLH1 and PMS2. The patient did not have a personal history of any visceral malignancy, but his father had died at the age of 46 years and a daughter at the age of 33 years from colonic carcinomas. The implications of this periocular sebaceoma for the Muir-Torre syndrome are explored.

Regression of Sebaceous Carcinoma of the Eyelid after a Small Incisional Biopsy: Report of Two Cases

Purpose

To report 2 cases of regression of sebaceous carcinoma of the eyelid after a small incisional biopsy.

Methods

Clinical, imaging, and histopathological findings are presented, with a literature review on regressing ocular tumors.

Results

Our first patient was a 79-year-old man who presented with a 10-month history of progressive left upper eyelid ptosis caused by an eyelid tumor with orbital involvement and confirmed on magnetic resonance imaging. Our second patient was a 70-year-old woman who presented with ptosis with a left upper eyelid mass. Both patients underwent a small incisional biopsy of their lesion. The histopathological diagnoses in both cases were consistent with sebaceous carcinoma. Both patients refused exenteration. Follow-up clinical examination and imaging disclosed total regression of the ptosis and of the neoplasm with no sign of recurrence in both patients over a 4-year period for Case 1 and a 7-year period for Case 2.

Conclusion

Regression following incisional biopsy of basal cell, squamous cell, and Merkel cell carcinoma, including of the eyelid, is well documented. To the best of our knowledge, our 2 cases of sebaceous carcinoma are the first to be reported with total involution clinically and on imaging of the tumor following partial incisional biopsy.

Current review of sebaceous cell carcinoma

PURPOSE OF REVIEW

Periocular sebaceous cell carcinoma is a rare malignancy that is often misdiagnosed leading to increased morbidity and mortality. This review aims to describe current knowledge on the disease to aid clinicians in timely diagnosis and treatment.

RECENT FINDINGS

New research has shown that the diagnosis of sebaceous cell carcinoma can be aided with immunohistochemical stains. A revision in the American Joint Committee on Cancer staging system incorporates new tumor size classifications in the staging of eyelid carcinomas. Wide local excision and Mohs micrographic surgery continue to represent the standard of care for initial treatment of localized disease.

SUMMARY

The current review highlights diagnostic and treatment modalities to allow clinicians to make timely diagnosis and tailor treatment plans for individual patient presentations.

Evaluation and comparison of staining patterns of factor XIIIa (AC-1A1), adipophilin and GATA3 in sebaceous neoplasia

BACKGROUND

Reliable nuclear immunohistochemical stains for sebaceous neoplasms have not been readily available. Positive nuclear staining has been reported for GATA3 and factor XIIIa (AC-1A1). We sought to determine the diagnostic utility of these nuclear stains by comparing their staining pattern to adipophilin, a consistently positive cytoplasmic stain.

METHODS

Cases with the diagnosis of sebaceous hyperplasia, sebaceous adenoma, sebaceous epithelioma/sebaceoma, sebaceous carcinoma, and nonsebaceous neoplasms (basal cell carcinoma and squamous cell carcinoma) were examined. Intensity and extent of staining of the basal cells and mature sebocytes were evaluated for each stain.

RESULTS

Factor XIIIa (AC-1A1) was 87.3% sensitive and 95.1% specific for all sebaceous neoplasms sand showed high inter-observer reliability. Adipophilin was 83.2% sensitive and 87.8% specific. GATA3 was the least sensitive (80.9%) and specific (75.6%) marker. When factor XIIIa was compared against composite staining of all three markers its staining was still uniquely significant (P = .0210).

CONCLUSION

Factor XIIIa (AC-1A1) is a sensitive and specific nuclear marker for sebaceous differentiation. Its diagnostic utility exceeds that of adipophilin. Factor XIIIa should be included in the expanding group of immunohistochemical and special stains which can be utilized to aid in the diagnosis of sebaceous neoplasms.

Updates in ophthalmic pathology

Ophthalmic pathology has a long history and rich heritage in the field of ophthalmology. This review article highlights updates in ophthalmic pathology that have developed significantly through the years because of the efforts of committed individuals and the confluence of technology such as molecular biology and digital pathology. This is an exciting period in the history of ocular pathology, with cutting-edge techniques paving the way for new developments in diagnostics, therapeutics, and research. Collaborations between ocular oncologists and pathologists allow for improved and comprehensive patient care. Ophthalmic pathology continues to be a relevant specialty that is important in the understanding and clinical management of ocular disease, education of eye care providers, and overall advancement of the field.

Sebaceous gland carcinoma of the ocular adnexa - variability in clinical and histological appearance with analysis of immunohistochemical staining patterns

PURPOSE

The purpose of the study was to evaluate the characteristics of sebaceous gland carcinoma (SGC) of the ocular adnexae, which is due to a high variability in clinical, histological and immunohistochemical characteristics often challenging to diagnose.

METHODS

Records of six patients with SGC were reviewed, who underwent surgical excision and who were histologically diagnosed with SGC. For comparison, there were specimens from four patients with basal cell carcinoma (BCC) and four patients with squamous cell carcinoma (SCC). Histological and immunohistochemical analysis included stains for HE, cytokeratins (CKpan, Cam5.2), epithelial membrane antigen (EMA), androgen receptor (AR441), perforin and adipophilin.

RESULTS

SGC's were located in the upper (n = 2) or lower (n = 4) eyelid and were associated with various presenting clinical signs including chalazion-like lesions with pyogenic granuloma (n = 1), papillomatous conjunctival tumors (n = 3), a hyperkeratotic exophytic neoplasm (n = 1) and an ulcerating crusted lesion resembling chronic blepharitis (n = 1). The treatment was tumor resection, followed (if necessary) by adjuvant therapy with topical Mitomycin C (n = 2). Histologic characteristics included basophilic pleomorphic cells with vacuolated cytoplasm, prominent nucleoli, mitotic figures and in some cases pagetoid spread (n = 2). CKpan, EMA and Cam5.2 showed strong positive immunoreactivity in all specimens (SGC, BCC, SCC). Perforin immunostaining showed a varying, but overall weak, non-specific cytoplasmatic staining reaction in all lesions. AR441 positivity was noted with variable intensity in almost all lesions and in particular in pagetoid spread in contrast to non-tumor cells. Adipophilin showed an annular staining of lipid granules in immature sebaceous cells in SGC in contrast to a more granular staining pattern in BCC and SCC.

CONCLUSION

SGCs display a variety of clinical signs and may mimic many other lesions. Tumor resection, followed by histological and immunohistochemical analysis, leads to the diagnosis and initiation of the proper treatment regimen. Herein, immunohistochemistry showed an unequivocal profile in SGC and did not allow for an exact differentiation from BCC and SCC by immunohistochemical means only. An extended evaluation of HE stains remains essential. However, immunohistochemistry can make relevant contributions to the diagnosis of SGC, especially in cases of inconclusive histology, by positive staining for adipophilin in immature sebaceous cells or by AR441 labeling in cases of pagetoid spread.

Sebaceous Carcinoma of the Eyelid

BACKGROUND

Periocular sebaceous carcinoma (PSC) is a rare but aggressive neoplasm that tends to clinically and histopathologically mimic other conditions. PSC can be challenging to diagnose using histomorphology alone given its overlap with 2 more common tumors that occur in this area (basal cell carcinoma [BCC] and squamous cell carcinoma [SCC]). Use of immunohistochemistry can help resolve this differential diagnosis.

METHODS

A review of the literature was performed, focusing on the epidemiology, morphology, and immunohistochemical features of PSC.

RESULTS

The most useful immunostains in the differential diagnosis of PSC are epithelial membrane antigen, Ber-Ep4, androgen receptor (AR), and adipophilin. To discern PSC from BCC, one should use EMA, Ber-Ep4, AR, and adipophilin, whereas discerning PSC from SCC can be achieved by evaluating AR and adipophilin. In addition, p53 and ERBB2 (formally known as HER2/neu) are other potentially useful immunohistochemical markers for the differential diagnosis of PSC.

CONCLUSIONS

Use of new immunohistochemical techniques, as well as the elucidation of molecular alterations, such as the presence of ERBB2 amplification, will advance our understanding of PSC.

Folliculosebaceous neoplasms: A review of clinical and histological features

Numerous benign and occasionally malignant tumors arise from the folliculosebaceous apparatus. Confusing terminology, rarity of malignant variants and overlapping histological features can lead to diagnostic uncertainty. This review highlights the clinical and histopathological features that help to classify these entities, as well as the various syndromes associated with certain members of this large family of tumors.

Risk Factors for Local Recurrence or Metastasis of Eyelid Sebaceous Gland Carcinoma After Wide Excision With Paraffin Section Control

PURPOSE

To identify risk factors for local recurrence and metastasis of sebaceous gland carcinoma (SGC) after wide excision with paraffin section control.

DESIGN

Retrospective, observational case-control study.

METHODS

Setting: Single institution.

PATIENT POPULATION

Thirty-four patients with SGC who had undergone excision with 5-mm surgical margins and paraffin section pathologic analysis. Observational Procedures: The following were considered potential risk factors for local recurrence/metastasis of SGC: patient's sex, patient's age, initial diagnosis at other clinics, topical treatments at other clinics, interval between appearance of symptoms and referral to our institution, tumor location, tumor origin, tumor presentation pattern, T category, tumor size, presence/or absence of pagetoid spread, tumor differentiation, mitosis grade, growth pattern. Logistic regression analysis was performed to identify the actual risk factors.

MAIN OUTCOME MEASURES

Risk factors for local recurrence or metastasis of SGC after wide excision with paraffin section control.

RESULTS

Involvement of both upper and lower eyelids, topical treatments at other clinics, multicentric origin, diffuse pattern, stage T3a, large tumor size, and a nonlobular pattern significantly influenced local recurrence/metastasis (P < .050). Pagetoid spread tended to affect local recurrence/metastasis (P = .052). The other items did not significantly influence local recurrence/metastasis (P > .050).

CONCLUSIONS

This study identified risk factors for local recurrence or metastasis of SGC after wide excision with paraffin section pathologic analysis. The results of this study will be helpful to surgeons when planning additional management, such as map biopsy or adjuvant treatment.

p16 Expression Is Not a Surrogate Marker for High-Risk Human Papillomavirus Infection in Periocular Sebaceous Carcinoma

PURPOSE

To evaluate the role of high-risk human papillomavirus (HR-HPV) infection in periocular sebaceous carcinoma (SC) using multiple methods of detection, and to determine whether p16 overexpression is present and can be used as a surrogate marker for HR-HPV.

DESIGN

Retrospective observational case series with laboratory investigations.

METHODS

Unstained paraffin sections of 35 cases of periocular SC were analyzed with immunohistochemistry for p16 and subjected to polymerase chain reaction (PCR) for HR-HPV. A subset of 18 lesions that were p16-positive was further studied with a novel method of mRNA in situ hybridization (ISH) for the detection of transcriptionally active HR-HPV, an advanced technique with an enhanced sensitivity and specificity.

RESULTS

The clinical findings were in keeping with those of comparable earlier studies. Strong immunohistochemical p16 positivity (meeting the criterion of >70% nuclear and cytoplasmic staining) was present in 29 of 35 cases of periocular SC (82.9%). The selected 18 p16-positive cases tested were negative for HR-HPV using mRNA ISH. PCR yielded unequivocal results with adequate DNA isolated in 24 cases, 23 of which were negative for HR-HPV. One case was positive for HPV type 16, which was found to be a false positive as collaterally determined by mRNA ISH negativity.

CONCLUSION

No evidence was found for HR-HPV as an etiologic agent in the development of periocular SC using multiple modalities to maximize sensitivity and specificity and reduce the limitations of any single test. p16 overexpression is common in periocular SC but unrelated to HR-HPV status. Although p16 may be used as a surrogate marker for HR-HPV status in other tissue sites, this interpretation of p16 positivity is not applicable to periocular SC.

Perforin expression in eyelid sebaceous carcinomas: a useful and specific immunomarker for the differential diagnosis of eyelid carcinomas

PURPOSE

Eyelid sebaceous carcinoma (SC) remains a common diagnostic pitfall for both the clinician and histopathologist. The aim of this study was to describe perforin as a new marker in the immunohistochemistry panel for SC.

METHODS

A total of 29 cases were retrieved from the Pathology archives, including 11 sebaceous neoplasms (nine SC; two sebaceomas), 10 squamous cell carcinomas (SCC) and eight basal cell carcinomas (BCC). These were stained using the monoclonal antibody for perforin, epithelial membrane antigen (EMA), Ber-EP4 and adipophilin (ADP). Sensitivity and specificity of perforin as an immunohistologic marker for sebaceous tumours were compared to EMA, ADP and Ber-EP4.

RESULTS

Perforin stained strongly 9/11 (81%) of the sebaceous neoplasms (SN), 7/9 SC and 2/2 of sebaceomas (2/2), similar to ADP. Epithelial membrane antigen (EMA) stained 8/9 SC and was negative (1/2) or only very weakly expressed (1/2) in sebaceomas. The specificity of perforin in identifying SN versus SCC and BCC was 100% (95% CI 69-100), while EMA specificity in identifying SN varied according the comparison group (SCC: 50%, 95% CI 18-81, 100% (95% CI 63-100). Perforin better highlighted the intraepithelial spread of SC than EMA. Ber-EP4 was strongly expressed in six of nine SC, but was consistently negative in sebaceomas.

CONCLUSIONS

The expression pattern of perforin in sebaceous neoplasms enables us to recommend the use of perforin as a new immunohistochemical marker for sebaceous neoplasms.

Sebaceous Carcinoma of the Ocular Region: The 2014 Professor Winifred Mao Lecture

Sebaceous carcinoma is a malignancy arising in the periocular region that can lead to blindness and tumor-related metastases. This study is a review of published literature and personal experience. This malignancy can arise from the sebaceous units in the tarsus (meibomian glands), in association with the cilia (Zeis glands), in the brow, and in the caruncle. There is a tendency for diffuse intraepithelial growth (pagetoid spread) that can be clinically invisible. Detection before lymph node metastasis is critical. This malignancy often masquerades as chronic unilateral conjunctivitis or blepharitis, typically in older patients. Management includes a 2-step approach with step 1 focused on eyelid and conjunctival map biopsies to determine the full extent of solid deep tumor and pagetoid spread. After complete review of all biopsies, step 2 is performed using local resection for all deep tumor, cryotherapy to pagetoid disease, and reconstruction. In most cases, the posterior lamella of eyelid is sacrificed with tumor removal, whereas the anterior lamella of the eyelid can be saved. After removal and cryotherapy, immediate reconstruction, using clean instruments, with buccal membrane graft for the posterior lamella and skin flap for the anterior lamella, is developed. For persistent or recurrent pagetoid disease, cryotherapy, topical mitomycin C, or plaque radiotherapy is provided. Exenteration is sometimes necessary. Sebaceous carcinoma, if detected early, can be managed with carefully planned map biopsy to determine tumor extent, followed by local resection, cryotherapy, and eyelid reconstruction. Orbital exenteration is occasionally necessary.

Sebaceous gland carcinoma of the eyelid: clinicopathological features and outcome in Asian Indians

PURPOSE

To study the clinical and histopathological features of eyelid sebaceous gland carcinoma (SGC) and to evaluate the prognosis in the Asian-Indian population.

METHODS

This is a retrospective study of 191 patients with SGC.

RESULTS

The mean age at presentation of eyelid SGC was 57 years (median, 56 years). The tumor epicenter was most commonly located in the upper eyelid (n=125, 65%). The mean tumor basal diameter was 15 mm (median, 10 mm). There was evidence of tumor extension into the orbit (n=30, 16%), paranasal sinuses (n=3, 2%), and brain (n=1, 1%). Wide excision biopsy (n=146, 78%) was the most common treatment modality. Tumor recurrence was noted in 42 (24%) patients over a mean follow-up period of 29 months (median, 20 months). On the basis of the Kaplan-Meier estimate, lymph node metastasis occurred in 18%, systemic metastasis was detected in 10%, and death occurred in 2% of patients at 10 years. On multivariate analysis, the factors predicting locoregional lymph node and systemic metastasis were medial canthal involvement (P=0.004; P=0.013), lateral canthal involvement (P=0.013; P=0.025), tumor basal diameter >10 mm (P=0.002; P=0.002), and perivascular invasion (P=0.043; P<0.001), respectively. The factors predicting death due to metastasis on multivariate analysis were medial canthal involvement (P=0.012) and tumor basal diameter >10 mm (P=0.001).

CONCLUSION

Advanced eyelid SGC is a tumor associated with poor prognosis. In this study, canthal involvement, larger tumor diameter, and perivascular invasion were poor prognostic factors.

Avoiding the major complication of ophthalmic pathology: misdiagnosis. A review of three common diagnostic challenges

Diagnostic errors in ophthalmic pathology are not uncommon. Pathology is a very subjective specialty with several biases dependent on such factors as training, experience, practice patterns, personal anecdotes, and inevitable human error. In addition to these factors, there are many cases where difficulty in diagnosis lies in differentiating between two very closely related, or similar appearing, entities that may have vastly different prognostic consequences. In this paper, we review three challenging areas wherein diagnostic dilemmas may occur. We outline some of the lessons we have learned in arriving at a correct diagnosis, which includes an admission of one's own limitations requiring consultation with other pathology subspecialists, and the use of immunohistochemistry.

Immunohistochemistry in dermatopathology

CONTEXT

Immunohistochemistry is not a diagnostic test but a highly valuable tool that requires interpretation within a context.

OBJECTIVE

To review the current status and limitations of immunohistochemistry in dermatopathology.

DATA SOURCES

English-language literature published between 1980 and 2014.

CONCLUSIONS

Although immunohistochemistry is rarely completely specific or sensitive, it is an important adjunctive technique in dermatopathology and can be helpful in a series of diagnostic dilemmas.