Treatment of squamous cell carcinoma of the eyelid with imiquimod 5% cream

Squamous cell carcinoma of the eyelid

Eyelid squamous cell carcinoma is a major type of rare eyelid cancer, together with basal cell carcinoma and sebaceous gland carcinoma. It is a painless disease that progresses slowly and is often detected by the appearance of nodules or plaques. Risk factors include exposure to ultraviolet light, fair skin, radiation and human papillomavirus infection. The standard treatment is surgical removal, and in cases of orbital invasion, orbital content removal is required. If sentinel node biopsy reveals a high risk of lymph node metastasis, adjuvant radiotherapy may be considered. Local chemotherapy, such as imiquimod and 5-fluorouracil, may be used for eyelid squamous cell carcinoma in situ. When surgery or radiotherapy is not recommended for distant metastases or locally advanced disease, drug therapy is often according to head and neck squamous cell carcinoma in Japan. The treatment often requires a multidisciplinary team to ensure the preservation of function and cosmetic appearance.

Periocular and ocular surface nonmelanoma skin cancer

Periocular and ocular surface nonmelanoma malignancies, including basal cell carcinoma (BCC), squamous cell carcinomas (SCC), and ocular surface squamous neoplasia (OSSN), are rare, but their management requires special considerations. The most common periocular malignancy is BCC, which constitutes 80% to 96% of tumors, followed by SCC, which represents 5% to 10% of tumors. OSSN represents a spectrum of diseases that encompass dysplastic alteration to the squamous epithelium of the eye. OSSN ranges from squamous dysplasia to conjunctival intraepithelial neoplasia/carcinoma in situ to invasive SCC, which is the most common ocular malignancy. These tumors can be staged using the eighth edition of the American Joint Committee on Cancer categorization system. The standard of care for periocular malignancies is Mohs micrographic surgery, while medical management with 5-fluorouracil (5-FU), interferon alfa-2b (INF), and mitomycin C (MMC) or "no touch" surgical excision are options for OSSN. Systemic therapies, including sonic hedgehog inhibitors for BCC and epidermal growth factor inhibitors and immune-checkpoint inhibitors for SCC, can be utilized for advanced disease. Recurrence rates are higher for periorbital and ocular malignancies than their respective cutaneous counterparts. These carcinomas and their respective treatments have unique side effects and considerations in an effort to preserve visual function.

Emerging therapeutic options for periorbital and orbital cutaneous basal and squamous cell carcinomas

PURPOSE

Recently, several new therapies have emerged to address locally advanced cutaneous basal cell and squamous cell carcinomas. Given the constraints of the ocular adnexa and orbit, this review was designed to discuss the role of these modalities in this region.

METHODS

A PubMed search was carried out to analyze the utility of United States Food and Drug Administration-approved therapies to address these malignancies. The data presented in the identified investigations were analyzed and abstracted.

RESULTS

Multiple novel interventions may be useful in the management of periocular cutaneous basal cell and squamous cell carcinomas, including imiquimod, hedgehog inhibitors, and immunotherapy. While many of these treatments have not been specifically explored in the orbit and ocular adnexa, the literature generally shows favorable response rates. However, adverse events were common in these studies.

CONCLUSIONS

Several novel treatments may address periorbital cutaneous malignancies, and these therapies may be particularly useful in patients with unresectable disease and those who are poor surgical candidates.

Treatment of periocular lentigo maligna with topical 5% Imiquimod: a review

Lentigo Maligna is a benign subtype of melanoma in situ and can progress to lentigo maligna melanoma, which is invasive. Complete surgical excision is the gold standard of treatment but requires large margins. If affecting the peri-ocular region, surgical excision leads to extensive defects, complex reconstructions, and functional impairment of the protection of the ocular surface. Here we review the reported literature about the use of Imiquimod 5% topical cream for lentigo maligna of the eyelid, the treatment outcomes, side effects and tolerance. In addition, the side effects of imiquimod treatment of non-LM lesions are described to help better inform the decision-making process. Treatment for peri-ocular Lentigo maligna showed a 56-86% complete treatment response and a 90% tolerability rate. However, reported treatment protocols vary and histopathological confirmation of clearance was only obtained in 56%. Further studies are required to determine the optimal treatment protocol to maximise clearance rates. Overall, Imiquimod was well tolerated in the peri-ocular area.

Long-term efficacy and safety of imiquimod 5% and fluorouracil 1% creams in medical monotherapy of complex eyelid basal cell carcinomas

PURPOSE

To study the long-term efficacy and safety of local application of imiquimod 5% and fluorouracil 1% creams in complex eyelid basal cell carcinomas (BCCs).

METHODS

A retrospective, non-comparative study in biopsy-proven, complex (involving canthi or >50% of eyelid length) eyelid BCC patients who were medically unfit for surgical procedures. All patients were medically treated with either of the creams using fixed-dose regimens for a minimum of 3 months. All received oral vitamin C 500 mg QID for 3 months as an adjunct for collagen healing. A minimum of "post-treatment" follow-up of 12 months was observed.

RESULTS

Of total 30 patients, imiquimod 5% and fluorouracil 1% were used in 16 and 14 patients, respectively. The mean age of our patients was 70.5 years. The co-morbidities included - severe coronary artery disease using blood-thinners (n = 19), poorly controlled diabetes (n = 12), poorly controlled hypertension (n = 6), on nebulization (n = 3), and tuberculosis with pulmonary fibrosis (n = 2). Complete clinical tumor resolution was noted in 10 and 8 patients over 12 and 16.5 weeks, respectively, in imiquimod and fluorouracil groups. Periocular skin erythema, chemical conjunctivitis, and skin depigmentation were seen in all the patients of imiquimod group. On the other hand, the local side-effect profile in fluorouracil patients was limited.

CONCLUSION

The medical treatment of complex eyelid BCC is a useful alternative to surgery in the elderly with significant co-morbidities. It provides a promising long-term relief with a tolerable side-effect profile. A prospective, randomized, double-blinded trial would provide stronger evidence for the efficacy of these drugs.

Tumor Clearance and Immune Cell Recruitment in UV-Induced Murine Squamous Cell Carcinoma Exposed to Ablative Fractional Laser and Imiquimod Treatment

BACKGROUND AND OBJECTIVES

Keratinocyte carcinoma (KC) is the most common cancer worldwide, and squamous cell carcinoma (SCC) is the second most frequent subtype. Ablative fractional laser (AFL)-assisted drug delivery significantly enhances the uptake of topically applied drugs. The objective of this study was to assess tumor response and perform a descriptive characterization of the local recruitment of immune cells and systemic immune mediator levels in an ultraviolet radiation (UVR)-induced murine SCC model after AFL treatment alone and combined with topical imiquimod.

STUDY DESIGN/MATERIALS AND METHODS

Immunocompetent hairless mice (C3·Cg/TifBomTac, n = 74) were irradiated with solar-simulated UVR until 3-mm SCCs developed. The mice were divided into four interventional groups: AFL alone, AFL + imiquimod, imiquimod alone, and untreated SCC controls. AFL was given as a single treatment, whereas imiquimod was applied daily until the mice were euthanized on Days 0, 2, 7, or 14. SCCs were photographed and measured (mm) to assess the therapeutic response. Skin samples were processed for histopathological and immunohistochemical analyses, as well as for flow cytometry. Cytokine expression changes in sera were analyzed using ELISpot cytokine arrays.

RESULTS

Treatment of mouse SCCs with AFL + imiquimod induced the most robust immune cell infiltration and the greatest proportion of tumor clearance compared to other interventions. Early innate immune cell infiltration was induced by AFL + imiquimod treatment as the number of neutrophils and macrophages had increased fourfold within 2 days of treatment initiation compared with untreated SCC control mice (P < 0.05). AFL treatment alone had a more limited effect, with a fourfold increase in neutrophils (P < 0.05) but no significant increase in the number of macrophages. Correspondingly, treatment with AFL + imiquimod had the greatest effects on the adaptive immune cell recruitment: CD4⁺ T-helper cells increased threefold at Day 7 compared with untreated SCCs (P = 0.0001) and, notably, cytotoxic CD8⁺ T cells increased 14-fold at Day 14 (P = 0.0112). In addition, FOXP3⁺ regulatory T cells (Tregs) increased 14-fold at Day 7 (P = 0.0026), suggesting the resolution of the inflammatory infiltration. AFL treatment alone induced a moderate immune cell infiltration (a twofold increase in CD4⁺ T-helper cells, P = 0.0200; a threefold increase in CD8⁺ T cells, P = 0.0100; and a 14-fold increase in FOXP3⁺ Tregs at Day 14, P = 0.0021), whereas imiquimod alone did not significantly increase cell counts. AFL + imiquimod treatment increased CXCL12 serum levels threefold at Day 14 (P = 0.0200).

CONCLUSION

AFL treatment alone and in combination with imiquimod induces substantial tumor clearance associated with local recruitment of innate and adaptive immune cells in UVR-induced murine SCCs. These results may provide a basis for new immunotherapeutic approaches to KC treatment.

Topical treatments for skin cancer

Skin cancer is a broad term used to describe a number of different malignant indications of the skin. Skin cancers mostly comprise of the keratinocyte cancers [Basal Cell Carcinoma (BCC) and cutaneous Squamous Cell Carcinoma (SCC)], and melanoma. Surgical excision of these malignancies has been the preferred treatment of patients for decades. However, the decision to perform surgery can be affected by various considerations, including co-morbidities of the patient, the anatomical site of the lesion and potential intolerance for repeated excisions. Topical treatment of skin cancer may therefore be more appropriate in certain instances. Topical treatment potentially allows for higher drug levels at the tumor site, and may result in less overall toxicity than systemic agents. This review will specifically address the current agents used in topical treatment of skin cancers, and introduce emerging treatments from the natural product field that may also find utility in these indications.

Electrochemotherapy and Ablative Therapies in Non-melanoma Skin Cancer

Although surgery and radiotherapy remain the most commonly used treatments for non-melanoma skin cancer, there are a variety of alternatives. Here we discuss the use of electrochemotherapy and ablative treatments and examine the evidence for their effectiveness against a number of non-melanoma skin cancers.