Conservative surgery in the treatment of giant cell tumor of the sacrum: 35 years' experience

OBJECT There is no consensus regarding the appropriate treatment of sacral giant cell tumor (GCT). There are 3 main management problems: tumor control, neurological loss, and pelvic instability. The objective of this study was to examine oncological, neurological, and structural outcomes of sacral GCT after intralesional excision and local intraoperative adjunctive treatment. METHODS The authors retrospectively reviewed the records of 24 patients with sacral GCT who underwent conservative surgery (intralesional resection/curettage) at Memorial Sloan Kettering Cancer Center from 1973 through 2012. They analyzed patient demographic data, tumor characteristics, and operative techniques, and examined possible correlations with postoperative functional outcomes, complications, recurrence, and mortality. RESULTS There were 7 local recurrences (30%) and 3 distant recurrences (13%). Three of 24 patients (12.5%) had significant neurological loss after treatment-specifically, severe bowel and/or bladder dysfunction, but all regained function within 1-4 years. Larger tumor size (> 320 cm³) was associated with greater postoperative neurological loss. Radiation therapy and preoperative embolization were associated with prolonged disease-free survival. There were no local recurrences among the 11 patients who were treated with both modalities. Based on radiographic and clinical assessment, spinopelvic stability was present in 23 of 24 patients at final follow-up. CONCLUSIONS High local and distant recurrence rates associated with sacral GCT suggest the need for careful local and systemic follow-up in managing these patients. Intraoperative preservation of sacral roots was associated with better pain relief, improvement in ambulatory function, and retention of bowel/bladder function in most patients. Fusion and instrumentation of the sacroiliac joint successfully achieved spinopelvic stability in cases deemed clinically unstable. Despite improvement in the management of sacral GCT over 35 years, a need for novel therapies remains. The strategy of combining radiotherapy and embolization merits further study.

Primary malignant giant-cell tumor of bone has high survival rate

BACKGROUND

Malignant giant-cell tumors (MGCT) comprise 2-9% of all giant-cell tumors (GCTs). The limited existing studies fail to distinguish primary, secondary, or postradiation cancers, making it difficult to design rational treatment strategies. This study compared malignant to benign GCTs and defined the clinical outcome of the patients in a large series of case-matched patients from a single institution.

METHODS

Clinical, radiological, and outcome features were compared between 26 malignant and 244 benign GCTs treated in our institution. Five postradiation cancers were excluded. We also performed a 1:2 case-matched comparison of patients with malignant and benign disease.

RESULTS

Distal femur (P = 0.019), proximal tibia (P = 0.032), and distal tibia (P = 0.049) had a higher frequency of MGCT. Campanacci stage 1 tumors had a low probability of malignancy (P = 0.017). MGCT were less likely to have aneurysmal bone cyst changes. The 5-year recurrence-free status probability was 80% for malignant and 91% for benign cases in matched groups. The difference in the recurrence rate between benign and malignant groups was not statistically significant (P = 0.24). Functional impairment and limited activity were greater in MGCT patients than in benign GCT patients, whether treated by resection/amputation or curettage/cryosurgery.

CONCLUSIONS

We found that malignant and benign GCT have similar epidemiology and that recurrence was higher in MGCT (20 v 9%). Local recurrence for MGCT was not statistically different for excision versus intralesional therapy, but there was little statistical power. Finally, the 16% mortality for patients with MGCT suggests low-grade malignancy.