INTRODUCTION: Giant cell tumors (GCT) of the hand are relatively common and have a good prognosis, but the risk of recurrence is high. The goal of this study was to evaluate the long-term clinical results of a consecutive series of patients and to determine the risk factors for recurrence. MATERIAL AND METHODS: This was a retrospective study of 96 patients (57 women, 39 men) operated between February 1982 and October 2005 for GCT of the tendon sheaths in the hand. The average age at the time of the procedure was 47.7±14.5 years (range 13-75). All the patients were reviewed by an independent surgeon. The following were recorded: clinical result (QuickDASH, satisfaction), recurrence, histological appearance of tumor, location of tumor, excision margins and extension into the neighboring anatomical structures (tendon, joint). The tumor was located in the index finger in 29 cases, middle finger in 23 cases, thumb in 21 cases, ring finger in 11 cases, little finger in 11 cases, hypothenar area in two cases and thenar area in one case. In all cases, the lesion was isolated. The swelling was palmar in 27 cases, dorsal in 20 cases and medial or lateral in 59 cases. The most common joint location was the DIP joint (35% of cases). The swollen area was sensitive in 12 cases. The time from the appearance of the tumor to physician consultation ranged between 1 month and 7 years. Before the surgery, standard X-rays were taken in all patients; ultrasonography was also performed in eight patients and MRI in one patient. The tumor had an average diameter of 15.8±2.6mm (range 5-30). Histological analysis revealed a multilobed lesion with multinucleated giant cells, with or without encapsulation. RESULTS: The average follow-up at the time of review was 12.1±3.8 years (range 5-29). There were eight recurrences in seven patients (8.3%). The average time to recurrence was 2.75±2 years (range 1-6.5). In every case of recurrence, there had been intra-articular tumor development and/or tendon destruction (P<0.01). There was one functional complication: one DIP joint fusion secondary to one of the recurrences. The average QuickDASH was 2.3/100 (range 0-31). CONCLUSION: Giant cell tumors of the synovial sheaths in the hand are benign lesions where recurrence is the primary risk. The recurrence typically occurred within 36 months of the excision. Intra-articular tumor development, marginal resection and tendon involvement seem to contribute to recurrence. There was no correlation found between the histological type of tumor (encapsulated or not) and recurrence. LEVEL OF PROOF: IV.