Treatment of a recurrent keratoacanthoma with oral isotretinoin

Structure-Activity Relationships and Therapeutic Applications of Retinoids in View of Potential Benefits from Drug Repurposing Process

Vitamin A, an essential micronutrient, is integral to various biological processes crucial for organismal development and maintenance. Dietary sources of vitamin A encompass preformed retinol, retinyl esters, and provitamin A carotenoids. Retinoic acid (RA), a key component, plays pivotal roles in vision, cell proliferation, apoptosis, immune function, and gene regulation. Drug repurposing, an effective strategy for identifying new therapeutic applications for existing drugs, has gained prominence in recent years. This review seeks to provide a comprehensive overview of the current research landscape surrounding retinoids and drug repurposing. The scope of this review encompasses a comprehensive examination of retinoids and their potential for repurposing in various therapeutic contexts. Despite their efficacy in treating dermatological conditions, concerns about toxicity persist, driving the search for safer and more potent retinoids. The molecular mechanisms underlying retinoid activity involve binding to retinoic acid receptors (RARs) and retinoid X receptors (RXRs), leading to transcriptional regulation of target genes. This review seeks to shed light on the possibilities for repurposing retinoids to cover a wider spectrum of therapeutic uses by exploring recent scientific progress. It also aims to offer a more comprehensive understanding of the therapeutic prospects of retinoids and the broader impact of drug repositioning in contemporary medicine.

Oral Isotretinoin and Its Uses in Dermatology: A Review

In 1982, the Food and Drug Administration (FDA) of the United States of America approved isotretinoin (13-cis-retinoic acid), a retinoid derivative of vitamin A, to treat severe recalcitrant acne vulgaris. Apart from its prescribed use for severe acne, evidence suggests that isotretinoin is commonly used off-label to treat mild-to-moderate acne, inflammatory skin conditions, genodermatoses, skin cancer, and other skin disorders. This is due to its anti-inflammatory, immunomodulatory, and antineoplastic properties. Some "off-label" use is successful, while others are ineffective. Therefore, this information is essential to clinicians for deciding on the appropriate use of isotretinoin. In this article, we aim to review the most updated evidence-based data about the use of oral isotretinoin in dermatology.

The diagnostic value of imaging techniques for keratoacanthoma: A review

Keratoacanthoma (KA) is a fast-growing skin tumor with solitary KA being the most common type. KAs rarely metastasize and subside spontaneously. Although histopathology is the gold standard for the diagnosis of KA, its histopathological features are sometimes difficult to distinguish from those of other skin tumors. Imaging studies have certain advantages in the preoperative diagnosis of KA; they not only show the exact shape of the lesion but can also accurately determine the extent of the lesion. Combined with histopathological examination, these findings help establish a diagnosis. By summarizing the imaging features of KA, this article aimed to improve radiologists' understanding of the disease and help in the clinical and differential diagnosis of KA.

Intralesional Methotrexate Treatment for Keratoacanthoma Tumors: A Retrospective Case Series

Background:

Intralesional methotrexate (IL-MTX) is an effective treatment for keratoacanthoma.

Objective:

We sought to determine the response rates and adverse events in KA treated with intralesional methotrexate.

Methods:

All cases of KA treated with intralesional methotrexate at our institutions from 2001 to 2009 were systematically reviewed.

Results:

Forty-six cases of KA treated with IL-MTX were identified. A complete resolution was achieved in 74% of patients, requiring an average of 1.8 injection sessions, for a mean total dose of 10 mg. Adverse events did not occur.

Limitations:

The follow-up period was short, and there was no histologic confirmation of the initial diagnosis.

Conclusion:

IL-MTX is an effective and well-tolerated alternative to surgery for the treatment of KA.

[Intralesional infusion of methotrexate as neoadjuvant therapy improves the cosmetic and functional results of surgery to treat keratoacanthoma: results of a randomized trial]

BACKGROUND

Keratoacanthoma is currently considered to be an in situ squamous cell carcinoma that mainly affects patients over 70 years of age. The tumor has a good prognosis and, in some cases, can resolve spontaneously. Treatment involves simple excision. However, since the tumors generally occur on the face or extremities and display rapid growth, aggressive surgery may be required and the cosmetic results may be poor.

OBJECTIVE

The primary study objective was assessment of the efficacy of presurgical intralesional methotrexate infiltration to reduce the size of the tumor and the corresponding surgical defect.

MATERIAL AND METHODS

A prospective, randomized study was undertaken in patients with a diagnosis of keratoacanthoma of at least 1.5 cm who were seen in our service between January 2009 and January 2010. Two groups were established: one receiving a single infiltration of methotrexate prior to surgery and another that did not receive methotrexate.

RESULTS

Of the 25 patients included in the study, 10 received neoadjuvant intralesional methotrexate (group A) and 15 underwent surgery without prior infiltration of methotrexate (group B). The patients in group A displayed a reduction of between 50% and 80% in the size of the lesion prior to surgery. No complications were observed either in relation to methotrexate infusion or surgery. In group B, only 1 patient had a slight reduction in the dimensions of the lesion prior to surgery. In the remaining cases, the lesions remained similar (4 cases, 26%) or had increased in size (10 cases, 66%) at the time of surgery. Five patients in this group required hospital admission following surgery.

CONCLUSIONS

Neoadjuvant intralesional methotrexate is well tolerated and reduces the need for aggressive surgery in elderly patients with keratoacanthoma measuring more than 1.5 cm on the face or extremities.

Intralesional methotrexate treatment for keratoacanthoma tumors: a retrospective study and review of the literature

BACKGROUND

Intralesional methotrexate (MTX) is an effective treatment for keratoacanthoma (KA).

OBJECTIVE

We sought to systematically examine response rates and adverse events in KA treated with intralesional MTX.

METHODS

All cases of KA treated with intralesional MTX at our institution from 1991 to 2006 were identified. A MEDLINE and PubMed search of cases of KA treated with intralesional MTX was also performed.

RESULTS

In all, 38 cases of KA treated with intralesional MTX were identified: 18 from our institution and 20 from the literature. Intralesional MTX achieved resolution in 92%, requiring an average of 2.1 injections an average of 18 days apart. Adverse events were rare, with two reports of pancytopenia in patients with chronic renal failure.

LIMITATIONS

Use of single case reports, small series, and retrospective analysis are limitations.

CONCLUSION

Intralesional MTX is a useful nonsurgical therapy for the treatment of KA. Histologic diagnosis before initiation of treatment is preferred. A complete blood cell count at baseline and during treatment should be considered to monitor for potential cytopenia.

Periocular squamous cell carcinoma

Squamous cell carcinoma (SCC) is the second most common eyelid malignancy and its incidence is increasing. Because of its variable clinical presentation, SCC may be difficult for even the experienced clinician to diagnose. Hence, all suspicious lesions warrant biopsy. As SCC behaviour may range widely in aggression, management should be individualized based on tumour (e.g. size, location, grade, histological subtype, previous recurrence, perineural invasion) and patient factors (e.g. age, health). Treatment of eyelid SCC should include margin control whenever possible for the highest cure rate in this high-risk area. Immediate histological monitoring of surgical margins with frozen sections or Mohs' micrographic surgery also allows for smaller margins of excision in an area where tissue conservation is important. Other special considerations in the periocular area include maintaining a high level of suspicion for perineural invasion as this may be associated with a poorer prognosis.

Keratoacanthoma as a postoperative complication of skin cancer excision

BACKGROUND

Keratoacanthomas usually occur spontaneously as a single rapidly growing tumor on sun-exposed skin. Multiple keratoacanthomas are rarely seen. Keratoacanthomas may also develop after trauma, laser resurfacing, radiation therapy, and at the donor site after skin grafting.

OBJECTIVE

We report 6 cases of keratoacanthomas that developed in and around healing and healed surgical sites after treatment of skin cancer. These tumors developed 1 to 3 months after surgery and were sometimes multiple.

METHODS

We performed follow-up examinations of patients' wounds after the treatment of skin cancer. Histological examination of nodules developing in the margins of healing wound sites and in the scars of healed wound sites after Mohs micrographic surgery revealed keratoacanthomas.

RESULTS

The tumors presented as a rapidly growing nodule or nodules, with the typical morphology and pathology of keratoacanthoma. One patient developed multiple keratoacanthomas at surgical and nonsurgical sites. These nodules were treated by a combination of excision, curettage and electrodesiccation, and oral isotretinoin, 4 mg/d.

CONCLUSION

Keratoacanthoma must be considered in the differential diagnosis of a rapidly growing nodule within or around the surgical site after skin cancer surgery.

A case of multiple keratoacanthoma centrifugum marginatum

BACKGROUND

Keratoacanthoma centrifugum marginatum is a rare variety of keratoacanthoma, usually presented and classified as solitary keratoacanthoma. Reported cases of multiple keratoacanthoma centrifugum marginatum are exceptional in the literature.

OBSERVATIONS

A 21-year-old man presented for evaluation of erythematous papules and plaques on both legs that had had a peripheral growth over the past year. Clinical and histologic examination showed typical features of keratoacanthoma centrifugum marginatum. Owing to the multiplicity and size of the lesions, treatment with oral isotretinoin was started. It was ineffective. Subsequent treatment with methotrexate combined with oral prednisone led to the regression of all lesions.

CONCLUSIONS

The exceptional case of a man with multiple keratoacanthoma centrifugum marginatum is reported. Treatment with methotrexate combined with oral prednisone was effective. This case illustrates how some variants of keratoacanthomas do not really fit into the current classification and how complex the treatment of these tumors is.

Persistent keratoacanthoma: challenges in management

BACKGROUND

Keratoacanthoma is a common cutaneous neoplasm, although the persistent form is less common and often more difficult to manage. Multiple treatment approaches have been attempted with variable efficacy. Establishing the diagnosis and selecting a treatment plan for persistent keratoacanthoma is often challenging.

OBJECTIVE

Our purpose is to describe the difficulty one may encounter in the diagnosis and treatment of persistent keratoacanthoma. Hopefully, review of this clinical conundrum may facilitate the management of the reader's future patients.

METHODS

We describe a case of persistent keratoacanthoma where the diagnosis was initially elusive and the management challenging. Our thought process during each stage of diagnosis and management is described in the form of "issues" with references to the appropriate literature.

RESULTS

After several diagnostic and therapeutic interventions, successful treatment was achieved with administration of oral isotretinoin. Long-term remission continued as the dosage was tapered.

CONCLUSION

Persistent keratoacanthoma may be challenging to diagnose and manage, presenting a clinical conundrum. Careful review of the clinicopathologic presentation and an understanding of the various treatment options may result in a successful outcome.