Annular Lesions Located on the Right Forearm

Clinical History

A 72-year-old Caucasian woman was referred to us because of presence of annular lesions located on the right forearm and present for 3 years. Notably, the patient had been affected by multiple myeloma (MM) immunoglobulin G (IgG)/lambda (stage IA) since 2005, in complete remission for 3 years.

Physical examination revealed erythematous, nonscaling lesions set on the right forearm measuring from 1 to 4 cm [Figure 1].

Figure 1.

Initial clinical presentation: Lesions were set on the right forearm measuring from 1 to 4 cm

The patient did not complain any itch from the lesions nor reported any previous intake of drugs. A punch biopsy revealed a lymphohistiocytic infiltrate, degenerated collagen, and mucin deposition [Figure 2].

Figure 2.

Histopathology of lesion showing area of degenerated collagen, lymphohistiocytic infiltrate, mucin deposition, and giant cells (H and E, ×40).

Question

What's your diagnosis?

Answer

Diagnosis

Atypical granuloma annulare (GA) associated with a multiple myeloma (MM) relapse.

Clinical Course

Initially, the patient was treated with daily betametasone ointment for 1 month without any improvement. Then, monthly triamcinolone acetonide subcutaneous infiltration was started, but was discontinued after 3 months without any improvement. Thereafter, 0.1% tacrolimus ointment was administered. After 2 months, the lesions began to turn pale and at the last follow-up the condition was stable [Figure 3]. In the meantime, the patient suffered an MM relapse and a cycle of melphalan chlorhydrate and prednisone was started.

Figure 3.

After 6 months the lesions kept about the same size, although began to turn pale

Discussion

GA is a benign, self-limiting, granulomatous dermatitis characterized by annular lesions, set on acral areas, such as the dorsum of the hands and feet. Women are most commonly affected. The etiology is still unclear, but it is thought that cell-mediated delayed type hypersensitivity could be involved. The appearance of GA has been reported in association with several diseases such as viral infections (e.g., Epstein-Barr virus, hepatitis C virus (HCV), and HIV), systemic illnesses (diabetes mellitus, thyroiditis, tuberculosis).[1] Furthermore, GA can precede or follow internal malignancies such as breast or colon carcinomas, Hodgkin and non-Hodgkin lymphoma, and leukemia (acute myelogenous leukemia, large granular lymphocytic leukmia).[2] In these cases, the clinical presentation can be polymorphous, including painful skin lesions on palms or soles.[3] Patients are commonly older than 60 years. The disease can often improve if the concomitant malignancy is successfully treated. GA therapies vary from psoralen + ultraviolet (PUVA) to topical and intralesional corticosteroids, antimalarials, pentoxifylline, retinoids, cyclosporine, laser, oral calcitriol, and dapsone.[4] However, it has not yet been established whether or not one of these should be considered as the best choice.[5]

There is an ongoing debate as to whether GA should be considered a paraneoplastic condition. However, many papers report GA in association with hematologic malignancies.[3]

In our case GA eruption was not the presenting symptom. GA eruption presented when MM began relapsing after 3 years of complete remission. However, the relapse was observed 3 years after the eruption. This finding corroborates with the experiences of Hinckley et al.,[6] and Vestey et al.,[7] with four GA cases characterized by an underlying myelodysplastic syndrome. In particular, two patients presented an acute myeloid leukemia.

To our knowledge, we report for the first time a case of MM presenting a GA eruption. This case leaves open the question whether GA eruption should be considered as a paraneoplastic lesion, both in terms of predicting and as sign of clinical worsening.