Molecularly targeted agents in oculoplastic surgery

Erdheim-Chester Disease With Eyelid and Orbital Involvement: A Review of Treatment Modalities at One Institution From 2014 to 2022

PURPOSE

To review all cases of Erdheim-Chester disease (ECD) with orbital involvement treated at Bascom Palmer Eye Institute in Miami, Florida from 2014 to 2022 and compare presentations, treatment modalities, and outcomes.

METHODS

A retrospective chart review of all patients diagnosed with ECD who presented to Bascom Palmer Eye Institute from 2014 to 2022 was performed. Data collected included demographics, pretreatment history and ophthalmic examination, pathology report, treatment, subsequent examination, and relevant laboratory results. Histopathology, treatments, and outcomes were reviewed and compared between patients.

RESULTS

Four cases were included. Primary treatments included vemurafenib (n = 2), cobimetinib (n = 1), and prednisone (n = 1). All patients demonstrated improvement of ophthalmic symptoms. Vemurafenib was the only medical treatment that was tolerated well and resulted in significant improvement in proptosis despite some reported dry eye; all other medications were discontinued due to intolerable side effects.

CONCLUSIONS

BRAF inhibitors such as vemurafenib have been used as novel therapy in the treatment of ECD. Vemurafenib demonstrated its utility in reducing proptosis in ECD patients at one ophthalmic institution. Vemurafenib may be a favorable treatment option for BRAF-positive ECD patients presenting with orbital disease.

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.

New Targeted Therapies and Immunotherapies for Locally Advanced Periocular Malignant Tumours: Towards a New 'Eye-Sparing' Paradigm?

The management of periocular skin malignant tumours is challenging. Surgery remains the mainstay of treatment for localised eyelid cancers. For more locally advanced cancers, especially those invading the orbit, orbital exenteration has long been considered the gold standard; however, it is a highly disfiguring and traumatic surgery. The last two decades have been marked by the emergence of a new paradigm shift towards the use of 'eye-sparing' strategies. In the early 2000s, the first step consisted of performing wide conservative eyelid and orbital excisions. Multiple flaps and grafts were needed, as well as adjuvant radiotherapy in selected cases. Although being incredibly attractive, several limitations such as the inability to treat the more posteriorly located orbital lesions, as well as unbearable diplopia, eye pain and even secondary eye loss were identified. Therefore, surgeons should distinguish 'eye-sparing' from 'sight-sparing' strategies. The second step emerged over the last decade and was based on the development of targeted therapies and immunotherapies. Their advantages include their potential ability to treat almost all tumours, regardless of their locations, without performing complex surgeries. However, several limitations have been reported, including their side effects, the appearance of primary or secondary resistances, their price and the lack of consensus on treatment regimen and exact duration. The aim of this article was to review the evolution of the management of locally advanced periocular malignant tumours over the last three decades and highlight the new paradigm shift towards the use of 'eye-sparing' strategies.

Dacryoadenitis Associated With Juvenile Idiopathic Arthritis

A 14-year-old female with juvenile idiopathic arthritis presented with left-sided recurrent painful periorbital swelling of 5 months duration. MRI revealed enlargement of the left lacrimal gland with extensive inflammatory change involving the orbital and periorbital soft tissues. Lacrimal gland biopsy showed evidence of chronic inflammation, and she had intralesional steroid injection at the time of biopsy. She remained asymptomatic at 6-month follow-up visit. Although juvenile idiopathic arthritis is usually related to intraocular inflammation, it may rarely be associated with dacryoadenitis.

[Does orbital exenteration still has a place in 2019?]

INTRODUCTION

Orbital exenteration is a radical anatomically and psychologically disfiguring procedure. It is mostly performed for management of orbital cancers or cancers with orbital involvement. The lack of benefit in terms of overall survival and the development of new molecular therapies (targeted therapies, immunotherapy) in recent years leads us to question its use. The goal of our review is to answer to the following question: is orbital exenteration a viable procedure in 2019?

MATERIALS AND METHODS

A literature review was performed using the PUBMED and MEDLINE databases. The following terms were used then crossed with each other: "orbital exenteration", "exenterated socket", "overall survival", "life expectancy", "orbital reconstruction", "socket reconstruction". Oncology articles from the past 15 years were included and separated into those in the oculoplastic literature and those in the ENT literature.

RESULTS

Nineteen articles were included in this review. Eyelid tumours represent the main etiology of orbital exenteration. Basal cell carcinoma is the most frequently incriminated tumor, while sebaceous carcinoma and conjunctival squamous cell carcinoma are the most frequently encountered in Asian series. Non-conservative orbital exenteration is the most prevalent surgery performed. Orbital reconstruction depends on the surgeon's speciality: healing by secondary intention and split thickness skin grafts are mostly performed by oculoplastic surgeons, whereas regional or free flaps are mostly performed by ENT surgeons. Cerebrospinal fluid leakage is the most common intraoperative complication, encountered in 0 to 13 % of cases. The most common postoperative complications are ethmoid fistula and infection of the operative site, encountered in 0 to 50 % and 0 to 43 % of cases respectively. Orbital exenteration allows surgical resection of R0 tumors in 42.5 % to 97 % of cases. Overall survival following orbital exenteration is 83 % (50.5-97) and 65 % (37-92) at 1 and 5 years respectively. Identified risk factors for poor overall survival are: age, tumor histology (worse prognosis with choroidal melanoma, better prognosis with basal cell carcinoma), non-R0 surgical resection, locally advanced tumors (size>20mm, BCVA<20/400 and the presence of metastases at diagnosis). Recent studies have demonstrated favorable outcomes when managing locally advanced basal cell carcinoma, lacrimal gland cancer and conjunctival melanoma with targeted therapies or immunotherapies without performing orbital exenteration.

CONCLUSION

Orbital exenteration remains a major part of our therapeutic arsenal. Although orbital exenteration has failed to demonstrate any overall survival benefit, it allows satisfactory local control of the disease with an increasingly less invasive procedure. The development of targeted therapies and immunotherapies may change our therapeutic decisions in the future.

A Suicide Switch Directly Eliminates Intracellular scFv Oligomers in the Cytoplasm of Mammalian Cells

As intracellular antibodies (intrabodies) are highly promising tools for drug discovery, an innovative antibody screening platform in mammalian cells was previously developed by a single-chain Fv (scFv)-c-kit growth sensor, which successfully selected rabies nucleoprotein and phosphoprotein-specific intrabodies from a synthetic scFv library. Since the scFv-c-kit growth sensor releases a growth signal after forming oligomers due to binding to an oligomeric antigen, it is critical to use a library which does not contain self-oligomeric scFvs to avoid the off-target signal of the growth sensor. Here, a novel method to eliminate self-oligomeric scFvs directly in the cytoplasm of mammalian cells is presented. A suicide switch by fusing an scFv with a cell-death signaling domain to eliminate scFv oligomers is developed. It is found that among four cell-death signaling domains, a suicide switch by fusing scFv with Fas-associated death domain (FADD) can selectively reduce oligomeric scFvs. Furthermore, the library after eliminating scFv oligomers results in higher efficiency in the intrabody selection platform with a growth sensor. Collectively, the scFv-FADD suicide switch can be applied to eliminate oligomeric scFvs from a library, which can consequently improve the quality of intracellular scFv libraries and accelerate the discovery of intrabodies in the future.