Aneurysmal bone cyst: A review of 65 patients

Aneurysmal bone cysts (ABC) are benign but locally aggressive lesions. The treatment of ABC has evolved over the years, but curettage with or without local adjuvants still represents the standard. Less invasive methods such as embolization, sclerotherapy or RANKL inhibitors (Denosumab) are also established. The aim of this study was to report and compare the results of a series of patients mainly treated with curettage with and without subsequent phenolization.

65 patients with the unequivocal diagnosis of primary ABC were treated. 61 of them were located within the bone whereas 4 patients had an ABC of the soft tissues. All patient were treated surgically by means of curettage with or without adjuvants, resection, or with minimally invasive methods such as Polidocanol injections, embolizations or Denosumab treatment. In total 80 procedures had been performed.

Our patients had a mean age of 25.3 ± 16.0 years, ranging from 4 to 74 years. The most common skeletal locations were the pelvis in 23%, the femur in 18%, the tibia in 16% and the spine in 10%. Six lesions were resected and showed no recurrence. 5 patients were treated with polidocanol injections (n = 3) or embolization plus systemic treatment with Denosumab (n = 2). With embolization and Denosumab both patients showed stable disease and required no further treatment. Polidocanol injections resulted in stable disease with no further treatment required in one patient and in subsequent curettage with adjuvant phenolization in two other patients.In 54 initial curettages 21 were performed with adjuvant phenolization. In this group, 16 lesions healed (76%), 3 showed persistent disease and 2 patients had a local recurrence (9%). Out of 33 patients without phenolization 21 (64%) healed, 3 showed stable persistent disease and 9 (27%) experienced a recurrence. In total we performed 66 curettages, 27 with and 39 without adjuvant phenol treatment. Resolution was achieved in 19 (70%) and 25 (64%) of cases. respectively. Persistent disease was evident in 5 cases each and recurrence in 3 and 9 cases, respectively (n.s.).

Curettage is still the standard of treatment for ABC. Local recurrence does not depend on the use of adjuvant phenol as shown in this and other studies. Minimally invasive methods such as selective embolization and injections of sclerosing agents may result in healing or at least in tolerable persistence of residual lesions but needs repetitive treatments and does not show homogenous results throughout the institutions. Denosumab appears to be an additional option, especially in surgically critical locations such as the spine or the sacrum.