Calcareous lesions of the distal extremities resembling tumoral calcinosis (tumoral calcinosislike lesions): clinicopathologic study of 43 cases emphasizing a pathogenesis-based approach to classification.

Herein, we analyze the clinicopathologic features of 46 distal extremity lesions that have histologic features similar to conventional tumoral calcinosis (tumoral calcinosislike; TC-L). The study included 31 females and 12 males (whites:non-whites>3:1) ranging in age from 1 to 91 (mean, 39; median, 42) years. The lesions presented in fingers (n=20), feet (n=10), wrist (n=6), hands (5), toes (n=4), and ankle (n=1) were solitary in all but 5 patients and ranged in size from 0.3 to 4.5 (mean, 1.6; median, 1.4) cm. Chief initial complaints included presence of a painful (n=16) or asymptomatic (n=7) mass, and limitation of joint mobility (n=3). Pertinent clinical associations included antecedent trauma (n=7), scleroderma (n=3), long-standing osteoarthritis (n=3), bony deformities (n=5), including 2 infants with congenital hand malformations, and chronic renal failure (n=2). Patients were stratified into one of the 3 recognized clinical settings of TC: primary normophosphatemic (n=17), secondary (n=5), or primary hyperphosphatemic TC (n=1). The 20 remaining patients were placed in an "indeterminate TC" category. Most lesions were located in tenosynovial/fascial tissue, but 13 lesions involved dermis and 1 was intra-articular. Histologically, the process consisted of multiple cystic or cleftlike spaces bordered by histiocytes, osteoclastlike giant cells, and a variable inflammatory infiltrate and containing fibrin, granular calcific debris, and calcospherites. Pools of calcific debris bordered by sclerotic collagen and a sparse cellular element predominated in 4 cases. Cartilaginous metaplasia was identified in 10 lesions and evidence of hemorrhage or specific injury was observed in 12 examples. Follow-up data for 22 patients (interval range, 1 to 30 y; median, 6 y) revealed 17 individuals with no evidence of recurrent disease or the development of additional lesions after simple (local) excision. One patient (indeterminate TC) required reexcision of a thumb mass 1 year after surgery. All 3 scleroderma patients developed additional TC-L lesions. Acral TC-L lesions are histologically similar to conventional TC, but present as smaller size lesions. Most TC-L lesions are closely aligned with primary normophosphatemic or secondary TC. Acral TC-L lesions may be the first manifestation of scleroderma, where the process has the potential to follow an unrelenting course.