Treatment of Annular Elastolytic Giant Cell Granuloma With Topical Tretinoin

Annular elastolytic giant cell granuloma (AEGCG), also known as actinic granuloma, is a rare granulomatous skin disorder that usually develops in areas of actinic elastosis.¹ First described in 1975 by O’Brien et al, lesions are characterized by asymptomatic annular plaques with elevated and erythematous borders and slightly atrophic and hypopigmented centers.² Lesions are predominantly located on the head and neck and other chronically sun-exposed areas.^2,3 Both proper classification (either as a distinct entity or variant of granuloma annulare) and etiology are widely debated. The leading theory implicates a cell-mediated immunologic response to a weak antigen on elastic fibers that are likely altered due to photodamage.^3-5While a few cases of spontaneous resolution have been reported, those that are chronic are treated by a wide range of therapies with variable success.⁴ Three case reports have shown efficacy of acitretin and isotretinoin.^1,6,7 Here, we present a case of annular elastolytic giant cell granuloma responding to topical tretinoin therapy.

A 47-year-old healthy Hispanic woman presented to our dermatology clinic in February 2013 with a history of well-demarcated, firm, erythematous annular plaques with central clearing on the bilateral forearms and dorsal aspects of her hands (Figure 1A). Lesions were somewhat pruritic. Biopsy of a representative lesion showed a mild to moderate superficial palisaded lymphohistiocytic infiltrate with admixed multinucleate giant cells, several of which exhibited elastophagocytosis. The specimen was noted to lack discernible necrobiosis and increased mucin, arguing against granuloma annulare. On the basis of these histological findings and the clinical presentation, the patient was diagnosed with annular elastolytic giant cell granuloma. Initial treatment with three rounds of cryotherapy spaced one month apart and two months of twice daily topical clobetasol 0.5% ointment proved ineffective. Given her treatment-resistant lesions and desire for complete resolution, we decided to start isotretinoin; however, she was unable to obtain the medication due to inadequate insurance coverage. A trial of topical tretinoin was subsequently attempted. The patient used topical tretinoin 0.025% cream every other day for two months followed by daily usage for one month. She reported significant improvement with flattening of lesions after approximately six weeks of every-other-day usage with a sustained response at eight months follow-up (Figure 1B). She noted only mild dryness as a side effect.

Annular elastolytic giant cell granuloma (AEGCG) typically runs a chronic and persistent course. While some lesions may spontaneously resolve in a few months to years, most have a poor and often inconsistent response to a myriad of treatments with disparate mechanisms of action.⁴ Unsurprisingly, there are no randomized controlled trials to guide treatment decisions for this rare condition and thus, there is no standard therapy. A trial of cryotherapy or topical or intra-lesional steroids is often attempted first, although responses vary.^8-10 In addition, patients are counseled regarding sun protection and sun avoidance to prevent further lesions.11 Other case reports have documented responses to retinoid-PUVA (RePUVA)¹² and a combination of oral tranilast with topical pimecrolimus.13 For resistant cases, cyclosporine for eight weeks,¹⁴ systemic steroids,¹⁵ and antimalarial drugs, including chloroquine4 and hydroxychloroquine,¹⁶ have also shown success in limited case reports. However,