A 68-year-old woman presented in September 1995 with a chronic, painful, ulcerative lesion of the sole of the right foot (Fig. 1). This lesion had developed 10 years previously and had not healed despite the many local treatments prescribed by earlier specialists.
The patient had suffered from rheumatoid arthritis for 15 years, treated with 5 mg/day of prednisone. She reported that, some years previously, a pruritic, papular eruption appeared on her trunk and limbs. Some time later, she developed erosive lesions of the buccal mucosa, the spontaneous shedding of toenails (big toes of both feet), and a scarring alopecia of the scalp.
Physical examination disclosed a large, deep, polyangular ulcer (3 × 5 cm in diameter) on the heel of the right foot with an ill-defined border and a clean granulating base. The skin around the lesion was erythematous and scaling.
On the abdomen, there were several small residual hyperpigmented lesions of typical papules of lichen planus.
Both big toenails were completely absent. The buccal mucosa showed pigmentary lesions (greyish-brown) in a reticulated pattern. On the vertex of the scalp, there were several small areas of scarring alopecia.
No abnormality was detected on general systemic examination. The family history and past medical history were not significant. Results of routine laboratory examinations were normal (included hepatitis B surface antigen (HBsAg) and HCV), except for rheumatoid factor (positive) and Waaler-Rose test (positive).
A skin biopsy specimen from the right heel showed histologic changes of ulcerative lichen planus (orthokeratotic hyperkeratosis, focal parakeratosis, vacuolization with dense lichenoid lymphocytic reaction at the dermo-epidermal junction) defined (Fig. 2).
The patient refused skin grafting and, for this reason, was treated with etretinate at an initial dose of 1 mg/kg/day, decreasing the dose every 10 days. When she reached 10 mg/day, this dose was maintained for 6 months. The treatment produced a remarkable reduction of the lesion (healed by about 90%) (Fig. 3), but without any further improvement in the subsequent 18 months of follow-up.