Chondrosarcoma of the proximal phalanx of the fourth digit: a rare location.

INTRODUCTION: Cartilaginous tumors involving the small bones of the hands and feet are usually benign such as enchondroma, chondromyxoid fibroma and chondroblastoma. The small bones of the hands and feet are rarely involved by primary chondrosarcoma. Proximal phalanges are the most common sites in the hands, but the fourth digit is the least common site. CASE
PRESENTATION: We report a case of a 76-year-old Greek female who presented to our hospital with a painful swollen mass measuring 4.5 × 2.6 cm on the fourth digit of the left hand. The radiograph showed a destructive, permeative lytic tumor of the proximal phalanx with extension into soft tissue. The patient underwent curettage, and the microscopic examination of the specimen revealed grade 2 chondrosarcoma.
CONCLUSION: Cartilaginous tumors involving the small bones of the hands and feet are usually benign such as enchondroma, chondromyxoid fibroma and chondroblastoma. Primary chondrosarcoma is the third most common malignancy of bone after myeloma and osteosarcoma, but the small bones of the hands and feet are very rarely involved by chondrosarcoma (1% of all chondrosarcoma). However, in these cases differentiation between a benign lesion and chondrosarcoma may be difficult. Occasionally chondrosarcoma of the hands and feet is associated with multiple recurrences or distal metastasis.

Case Presentation

A 76-year-old Greek female presented to our hospital with a painful swollen mass measuring 4.5 × 2.6 cm on the fourth digit of the left hand. The symptoms were of long duration (several months). The radiograph showed a destructive, permeative lytic tumor of the proximal phalanx with extension into soft tissue. Linear areas of calcium deposit were present in the tumor. The soft tissue mass was relatively well marginated (fig. ). Procedures such as chest radiography and abdominal ultrasonography to look for metastases produced negative results. The treatment was curettage of the lesion, and the microscopic examination of the specimen revealed grade 2 chondrosarcoma (fig. , fig. ). Two years later, the patient showed no evidence of recurrence or metastasis.

Discussion

Primary chondrosarcoma is a tumor of adulthood and old age. The majority of patients are older than 50 years. Patients with secondary chondrosarcoma are somewhat younger, with approximately 52% being in the third and fourth decades of life [1, 2, 3]. Cartilaginous tumors involving the small bones of the hands and feet are usually benign such as enchondroma, chondromyxoid fibroma and chondroblastoma [1, 4]. Although chondrosarcoma is rare in these locations, the difficulty in differentiating enchondroma from well-differentiating chondrosarcoma is well recognized [1, 2, 5]. The distinction between them depends so much on the radiographic finding that a pure histological interpretation is hazardous [2]. Essential to differentiation from enchondroma may be cortical destruction, soft tissue mass and permeative pattern [1, 2].

Regarding the location of chondrosarcoma, proximal phalanges are the most common sites in the hands. The fifth digit has the highest incidence of chondrosarcoma and the fourth digit is the least common site in the hands. When distal phalanges of the hands are involved, the thumb is the most common site. The calcaneus is the most common site in the feet [1, 3, 6, 7, 8]. Secondary chondrosarcoma constitutes about 11% of all chondrosarcomas in small bones of the hands and feet [1, 3, 9, 10].

The treatment of chondrosarcoma is surgical excision with curettage, resection or amputation. Curettage of the lesion leads to a very high rate of recurrence. Chondrosarcoma is associated with metastasis although such metastasis is very rare [1, 2, 3, 6, 8, 11, 12, 13].

Disclosure Statement

All authors who have participated in this work take responsibility for the manuscript, which has never been published or submitted for publication elsewhere.