The molecular genetics of eyelid tumors: recent advances and future directions

Targeted therapy in ophthalmic oncology: The current status

There have been rapid advancements in the field of ocular oncology for the diagnosis and management of intraocular, adnexal, and orbital tumors. Targeted therapy is in the forefront of medical research in all fields including ocular oncology. Targeted therapy include drugs that target specific genetic mutations, pathways or proteins involved in the development of cancer. In contrast to traditionally used chemotherapy, drugs used in targeted therapy are highly specific for tumor cells and preserve the function of normal cells. This review aims to familiarize ophthalmologists with the drugs that are currently approved or undergoing clinical trials for use in ocular oncology. Targeted therapy is particularly useful for locally advanced or metastatic tumors, including but not limited to eyelid and periocular basal cell carcinoma, periocular cutaneous and conjunctival squamous cell carcinoma, ocular adnexal lymphoma, conjunctival melanoma, and uveal melanoma. The results are promising with improved survival outcomes and better tolerability than chemotherapeutic drugs.

Globe-sparing surgical treatment for periocular malignancies with anterior orbital invasion: a consecutive case series

PURPOSE

Orbital exenteration of periocular tumors complicated by orbital invasion is a heavy burden for patients and leads to disfiguring cosmesis and loss of vision. Here, we report our experience with globe-sparing surgery in a series of patients with periocular malignancies other than basal cell carcinoma (BCC), all exhibiting anterior orbital invasion.

METHODS

In this consecutive case series, we examined medical records of all patients between 2000 and 2018 with periocular malignancies (other than BCC) invading the anterior orbit (without extraocular muscle or scleral invasion) treated by one orbital surgeon (DP). The main outcome measures included local recurrence, regional and distant metastasis, survival, and visual acuity.

RESULTS

Nine patients were identified. Of the non-BCC cancers invading the orbit, squamous cell carcinoma (SCC) (44.4%) was the most prevalent type in our series. Excision included the removal of visibly distinguishable tumor and a free clinical margin of up to 5 mm with histological confirmation of radicality of the invasive tumor component. Reconstruction was achieved by a variety of oculoplastic reconstructive procedures. At a mean follow-up of 70 months (range 11-177 months), 8 out of 9 patients were still alive. Recurrence occurred in two patients with conjunctival melanoma (CM), and they were again treated with wide excision. Postoperative visual acuity remained stable or improved.

CONCLUSION

This retrospective case series demonstrates that globe-sparing excisional surgery can be considered in selected cases of periocular malignancies other than BCC with anterior orbital invasion, thus avoiding cosmetic disfigurement and loss of vision due to orbital exenteration.

Clinicopathological analysis of eyelid lesions in Sri Lanka

PURPOSE

We intended to review the clinical features and histological findings of eyelid lesions in Sri Lanka.

METHODS

We conducted a descriptive cross-sectional study to analyse clinicopathological characteristics of eyelid lesions from 2013 to 2017 in the National Eye Hospital of Sri Lanka.

RESULTS

The age of patients ranged from 3 months to 83 years (mean = 46 ± 21 years). The male-to-female ratio in the sample was 1:1.3. Among 654 histologically confirmed eyelid lesions, the majority (n = 407/654, 62%) were neoplastic lesions including 322 benign, 11 premalignant and 74 malignant neoplasms. The commonest benign tumour was seborrheic keratosis (n = 98), and the commonest non-neoplastic lesion was pyogenic granuloma (n = 64). Seventy-four patients had malignant neoplasia including 24 sebaceous carcinoma, 18 basal cell carcinoma, and 14 squamous cell carcinoma. The most common site of malignant lesions was the upper eyelid. The mean age of patients with malignant eyelid lesions was 64 ± 13 years.

CONCLUSIONS

Neoplastic lesions outnumbered nonneoplastic lesions, while benign neoplasia was more common than malignant neoplasia. In contrast to the western reports, the commonest malignant neoplasm was sebaceous carcinoma.

Novel MSH6 mutation predicted metastasis in eyelid and periocular squamous cell carcinoma

BACKGROUND

Our previous research revealed the relative local aggressiveness of eyelid and periocular squamous cell carcinoma (EPSCC), but its distinct genetic characteristics involved remain unknown.

OBJECTIVES

We conducted this study based on next-generation sequencing to identify the genetic distinctiveness of EPSCC and damaging mutations for possible etiology and poor prognosis.

METHODS

We performed sequencing using a 556-gene panel (smartonco) in 48 EPSCCs. Cox hazards model was applied to explore mutated genes that increase risk of metastasis and death. Pathogenesis of the mutations was predicted by sequence alignment algorithms.

RESULTS

The most commonly mutated genes were KMT2C (N=17, 35%), LRP1B (N=14, 29%), KMT2D (N=12, 25%), PTCH1(N=10, 21%) and TP53(N=10, 21%). DNA mismatch repair (MMR) genes (42%) like MSH6(19%) and MLH3(12%) were among the most frequently mutated genes. Cell cycle regulators including TP53(21%) and CDKN2A (10%) were less frequently mutated than in other squamous cell carcinomas (SCCs). Ultra violet exposure, MMR deficiency and aging were the main etiology. Of note, KMT2C has a deleterious mutation hotspot. Patients burdened with MSH6 mutation has a higher risk of overall metastasis (P=0.045, HR=5.165) and nodal metastasis (P=0.022, HR=14.038). Moreover, a hotspot mutation MSH6^E52A brought an even higher risk of nodal metastasis (P=0.011, HR=18.745).

CONCLUSIONS

EPSCCs displayed a unique mutation profile from cutaneous SCCs and mucosal SCCs. We have identified novel damaging mutations in epigenetic regulators like KMT2C boosted early onset of EPSCCs in addition to UVR, aging or MMR deficiency. And malfunction of MMR genes worsened prognosis.

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.

Six-gene-based prognostic model predicts overall survival in patients with uveal melanoma

BACKGROUND

Uveal melanoma (UM) is the most common primary intraocular tumor in adults, which has a high mortality rate and worse prognosis. Therefore, early potential molecular detection and prognostic evaluation seem more important for early diagnosis and treatment.

METHODS

Gene expression data were obtained from The Cancer Genome Atlas-Uveal melanomas database. Survival genes were identified by univariate analysis and were regarded to be associated with the overall survival of UM patients. Then, pathway enrichment analysis of these survival genes was performed. Robust likelihood-based survival model and multivariate survival analysis were conducted to identify more reliable genes and the prognostic signature for UM survival prediction. Two internal datasets and another two UM datasets from Gene Expression Omnibus (GEO) were used for the validation of prognostic signature.

RESULTS

Firstly, 2,010 survival genes were screened by univariate survival analysis. GO and KEGG analysis revealed that these genes were mainly involved in pathways such as mRNA processing, RNA splicing, spliceosome and ubiquitin mediated proteolysis. Secondly, a six-gene signature was identified by Robust likelihood-based survival model approach. The gene expression of the six genes can successfully divide UM samples into high- and low-risk groups and have strong survival prediction ability. What's more, the expression of six genes was compared in 80 healthy adipose tissue samples obtained from GTEx (Genotype-Tissue Expression) database and further validated in internal datasets and GEO datasets, which also can predict UM patient survival.

CONCLUSIONS

The six genes (SH2D3A, TMEM201, LZTS1, CREG1, NIPA1 and HIST1H4E) model might play a vital role in prognosis of UM, which should be helpful for further insight into the treatment of uveal melanoma.

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.

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.

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.

Sebaceous adenomas of the eyelid and Muir-Torre Syndrome

BACKGROUND/AIMS

Sebaceous adenomas (SAs) are rare, benign sebaceous gland tumours of the eyelid. SAs may be associated with primary internal malignancies. This association is known as Muir-Torre Syndrome (MTS). The purpose of this study was to approximate the prevalence of SAs, to determine the reliability of the clinical diagnosis of SAs and to demonstrate immunohistochemical staining of DNA mismatch repair proteins mutL homologue 1 (MLH1) and mutS homologue 2 (MSH2) for a case of MTS.

METHODS

We reviewed the histopathology reports from all eyelid specimens collected between 1993 and 2013 at the Henry C Witelson Ocular Pathology Laboratory to determine the proportion of SAs. For the SAs identified on histopathology, we looked at patient charts to see what diagnosis was originally suspected on clinical examination. Immunohistochemical staining for MLH1 and MSH2 was performed on all SAs to screen for MTS.

RESULTS

Of the 5884 eyelid specimens collected, 9 were SAs (6 women, 3 men; 42-72 years old). The diagnosis of SA was suspected clinically in only one of the nine cases based on the gross appearance of the eyelid lesion. Immunohistochemistry revealed one SA case with positive MLH1 expression and negative MSH2 expression. These findings prompted systemic work-up and this patient was diagnosed with MTS after discovery of a colon adenocarcinoma T2M0N0.

CONCLUSIONS

The diagnosis of eyelid SA is rare. The importance of this benign eyelid tumour stems from its association with internal malignancies in MTS. Immunohistochemical staining of mismatch repair proteins MLH1 and MSH2 is a valid and accessible strategy for investigating MTS in patients with SAs.

Eyelid sebaceous carcinoma: clinicopathologic and multiparametric immunohistochemical analysis that includes adipophilin

PURPOSE

To evaluate the fine cytopathologic features and immunohistochemistry of eyelid sebaceous carcinoma.

DESIGN

Retrospective clinicopathologic study.

METHODS

Clinical records and microscopic glass slides of 12 patients diagnosed with sebaceous carcinoma were reviewed. Paraffin-embedded tissue recuts were immunoreacted for epithelial membrane antigen (EMA), Ber-EP4, p53, Ki-67, and adipophilin for cytoplasmic lipid. Invasive growth and intraepithelial spread were analyzed separately. Cytoplasmic and nuclear characteristics were correlated with the results of the immunohistochemical profiling.

RESULTS

Five patients experienced recurrences, but no metastases or tumor-related deaths were discovered. The nuclei in 11 invasive tumor cells were typically round with finely divided, granular, or smudgy chromatin without prominent margination at the nuclear membrane; they exhibited small punctate nucleoli. Positivity for EMA (both diffuse and focal), p53 (72% of nuclei), and Ki-67 (45% proliferation index) was demonstrated. Adipophilin positivity in vesicular and granular forms was detected in paraffin sections in all invasive tumors, most prominently in moderately differentiated and well-differentiated lesions. Among 9 cases exhibiting intraepithelial extensions, 6 showed mostly granular positivity and 3 vesicular positivity. p53 identified residual atypical intraepithelial cells when conjunctival epithelial sloughing occurred.

CONCLUSIONS

Immunohistochemistry can make significant contributions to the diagnosis of sebaceous carcinoma. p53 and vesicular granular adipophilin positivity were highly reliable in supplementing the routine microscopic diagnosis of infiltrative tumors and both can be used in paraffin sections, thereby obviating cumbersome oil red O staining of frozen sections. The cells found in intraepithelial spread were strongly EMA and p53 positive, with more granular than vesicular adipophilin positivity.