Keratoacanthoma and Cutaneous Squamous Cell Carcinoma With PD-1 and PD-L1 Inhibitor Use.

This cross-sectional study assesses risk of dermatological immune-related adverse events associated with immunotherapy for cancer.

Multiple Keratoacanthoma-like Syndromes: Case Report and Literature Review.

Keratoacanthoma (KA) is a fast-growing skin tumor subtype that can be observed as a solitary lesion or rarely as multiple lesions in the context of rare genetic syndromes. Syndromes with multiple keratoacanthoma-like lesions have been documented as multiple self-healing squamous epithelioma (Ferguson-Smith syndrome), eruptive keratoacanthoma of Grzybowski, multiple familial keratoacanthoma of Witten and Zak Muir-Torre syndrome, and incontinentia pigmenti. The treatment approach of those entities is challenging due to the numerous lesions, the lesions' undefined nature, and the co-existence of other malignant skin tumors. Herein, we report a case of a 40-year-old woman who developed multiple treatment-resistant Ferguson-Smith-like keratoacanthomas with a co-existing large and ulcerated invasive squamous cell carcinoma and microcystic adnexal carcinoma on the scalp. Multiple keratoacanthomas on her extremities were successfully treated with oral acitretin (0.5 mg/kg/day) in combination with topical Fluorouracil (5-FU) 5%, while excision and plastic surgery restoration were performed to treat the ulcerated cancer lesion on her scalp. Due to the interesting nature of this rare syndrome, we performed a literature review including case reports and case series on multiple-KA-like lesions syndromes and focusing on diagnosis and therapy approaches. We also conducted a comparison of patient reports, which included assessing the clinical appearance of the lesions and evaluating the success and progress or the failure of various treatment approaches that were implemented.

Intralesional methotrexate as non-surgical therapy for giant keratoacanthoma on the nose.

Keratoacanthoma is an epithelial tumour derived from hair follicles. Clinical and histopathological features of keratoacanthoma can resemble that of squamous cell carcinoma. Different treatment alternatives have been described over the years including intralesional methotrexate injection. We present an interesting case of treatment of solitary keratoacanthoma lesion on the nose with intralesional methotrexate as non-surgical therapy.

Multiple Eruptive Keratoacanthomas Secondary to Nivolumab Immunotherapy.

Immune checkpoint inhibitors are increasingly being utilized for the treatment of advanced neoplastic disease and have been associated with wide-ranging cutaneous adverse effects. Though exceedingly rare, eruptive keratoacanthomas have been associated with the use of immune checkpoint inhibitors such as pembrolizumab and nivolumab, whose molecular target is the programmed cell death protein 1. Herein, we detail a case of numerous eruptive keratoacanthomas arising in a patient one month after initiation of nivolumab for recurrent metastatic oropharyngeal squamous cell carcinoma. Treatment with multiple rounds of intralesional corticosteroids and a several-month course of oral acitretin resulted in partial improvement. Subsequent treatment with intralesional 5-fluorouracil demonstrated near-complete resolution of the keratoacanthomas without discontinuation of nivolumab. Although eruptive keratoacanthomas secondary to immune checkpoint inhibitors are exceptionally rare, physicians should be aware of this cutaneous adverse effect as their use becomes more widespread.

Dilute Intralesional 5-Fluorouracil for the Treatment of Squamous Cell Carcinomas and Keratoacanthomas: A Case Series.

BACKGROUND: Intralesional 5-fluorouracil (5-FU) is a promising, yet sparsely studied alternative to surgical treatment for nonmelanoma skin cancer (NMSC).1 Previous studies of intralesional 5-FU have reported concentrations ranging from 30 to 50 mg/mL. To the best of our knowledge, this case series represents the first reported use of intralesional 5-FU 10.0 mg/mL and 16.7 mg/mL for NMSC. METHODS: A retrospective chart review identified 11 patients who received intralesional 5-FU 10.0 mg/mL and 16.7 mg/mL for 40 cutaneous squamous cell carcinomas and 10 keratoacanthomas. We describe the characteristics of these patients and calculate the clinical clearance rate of dilute intralesional 5-FU therapy for NMSC at our institution. RESULTS: Dilute intralesional 5-FU successfully treated 96% (48/50) of the study lesions, providing complete clinical clearance in 82% (9/11) of patients across a mean follow-up time of 21.7 months. All patients tolerated their treatments well with no reported adverse effects or local recurrences. DISCUSSION: The use of more dilute preparations of intralesional 5-FU for NMSC may be a means of reducing cumulative dose and dose-dependent adverse reactions while maintaining clinical clearance. J Drugs Dermatol. 2023;22(5): doi:10.36849/JDD.5058.

To treat or not to treat: PD-L1 inhibitor-induced keratoacanthoma and squamous cell carcinoma.

Keratoacanthoma (KA) and squamous cell carcinoma (SCC) are rare side effects of programmed cell death ligand-1 (PD-L1) inhibitors that can disrupt therapy. There is no consensus on optimal treatment. We investigated the management strategy and factors influencing pathophysiology. An institutional cancer registry and literature search were used for this retrospective study. Only PD-L1-induced KA and SCC cases were included. Pathology specimens were stained with immune markers and management strategies were analyzed. Four cases were identified at our institution. Immunohistochemistry of atypical keratinocytes revealed PD-1/PD-L1 positivity, high p53, and low bcl-2 for all cases with differential expression of CD44 and beta-catenin for KA versus SCC. Nivolumab was continued or temporarily held with complete resolution. In addition, a literature search identified 30 additional cases of KA/SCC after PDL-1 inhibitor use. The most common treatment was excision/destruction followed by topical and/or intralesional corticosteroids. Therapy was definitely withheld in 22% of KA patients and in 9% of SCC cases. The expression of PD-L1 by atypical keratinocytes helps to explain the effects of nivolumab on the development of cutaneous neoplasms. The expression of immune markers provides mechanistic insights into pathophysiology. Management may be achieved with conservative therapy and without treatment interruption.

Treatment of Reactive Keratoacanthomas with Acitretin Following Multiple Excisions and Mohs Surgery for Recurrent Squamous Cell Carcinoma.

Surgical intervention is seen as the gold standard in the treatment of Squamous cell carcinoma. Yet, in cases of recurrence, repeated surgical procedures may unwittingly foment the rise of reactive keratoacanthomas at the surgical margins or edge of a newly placed skin graft.

Debulking followed by intralesional 5-fluorouracil for the treatment of cutaneous squamous cell carcinoma and keratoacanthoma: A retrospective analysis.

Debulking followed by intralesional 5-fluorouracil (deb-IL5FU) is a nonsurgical modality which has been used to treat skin cancer anecdotally for many years. There are few in depth studies examining this technique and success rate of intralesional 5-fluorouracil (IL5FU) for the treatment of cutaneous squamous cell carcinoma (cSCC). To evaluate the response rate of deb-IL5FU for the treatment of cSCC and to determine which patient factors were associated with tumor clearance or treatment failure. A retrospective chart analysis of patients with the diagnosis of cSCC or keratoacanthoma (KA) and subsequent deb-IL5FU treatment. Sixty-one patients with a total of 315 tumors (cSCC and KA), were treated using deb-IL5FU. The overall tumor clearance rate was 89%. This was highest for well-differentiated SCC, SCC, KA-type SCC, and KA. Tumors on the trunk and extremities showed high clearance rates while tumors on the scalp/face/neck/ears showed lower clearance rates. Immunocompetent patients cleared more tumors compared to immunocompromised patients. Limitations included the retrospective nature of this analysis as well as a small sample size. Treatment of cSCC and KA with deb-IL5FU demonstrated high tumor clearance rates. Lower rates of clearance were seen in males, immunosuppressed patients, tumors located on the scalp and face/neck/ears.

Sorafenib-related generalized eruptive keratoacanthomas (Grzybowski syndrome): a case report.

BACKGROUND: Sorafenib is an oral multikinase inhibitor that targets Raf serine/threonine receptor tyrosine kinases and inhibits tumor cell growth and angiogenesis. Cutaneous toxicities of sorafenib are common, including cutaneous eruptions (such as truncal erythema and seborrheic-dermatitis-like changes) and hand-foot syndrome. Keratoacanthomas and squamous cell carcinomas have been reported previously; however, we report a case of multiple eruptive keratoacanthomas in the form of Grzybowski syndrome after initiation of sorafenib. CASE PRESENTATION: We report a 63-year-old Caucasian male who developed multiple cutaneous eruptive keratoacanthomas after starting sorafenib 400 mg twice daily. He had a known history of hepatitis-C-related cirrhosis and hepatocellular carcinoma, and previously had actinic keratosis and skin squamous cell carcinoma excision. Approximately two and a half months after starting sorafenib, the patient initially developed two lesions, one on each forearm, and after excision, these lesions demonstrated histological features of squamous cell carcinoma. One month later, the patient presented with approximately 48 new skin lesions of varying size on the back, bilateral upper limbs, and face requiring excisional biopsy of a large number of these lesions. Histopathology showed eruptive invasive keratoacanthomas (Grzybowski syndrome). Sorafenib was temporarily stopped and subsequently restarted at a lower dose. Acitretin 25 mg daily was commenced after few weeks, and no further keratoacanthomas developed during his treatment. CONCLUSIONS: We report a unique case of sorafenib-associated Grzybowski syndrome. Temporary interruption and dose reduction of sorafenib and use of acitretin appeared to prevent further development of keratoacanthomas.