Intralesional vs. extralesional procedures for low-grade central chondrosarcoma: a systematic review of the literature

Chondroid lesions are very common bone tumors. In most cases, they are benign enchondromas (EC) and, in a minor percentage, chondrosarcomas (CSs), the malignant counterpart. In the latter cases, surgery is the mainstay treatment, because they are chemo- and radio-resistant unless dedifferentiation occurs. If resection is recognized as the gold standard for intermediate-, high-grade tumors, and for low-grade chondrosarcoma (LG-CS) located in the spine and pelvis to reduce the risk of local recurrence, there is still no consensus in literature on the treatment of central low-grade chondrosarcoma (cLG-CS) located in the limbs. Our aim is to perform a review of literature on evidence supporting this approach or not. An electronic research of the medical archives was carried out in March 2017 seeking papers evaluating the results of curettage and resection in cLG-CS. We selected 13 studies corresponding to our criteria. Unfortunately, they were descriptive, retrospective, non-randomized studies. We identified a population of 471 patients for a total of 473 low-grade chondrosarcomas. Two hundred and ninety-nine lesions were treated with curettage and 174 with wide surgery. The two groups were not homogeneous for diagnosis, size and staging, so no comparison between resection and curettage was possible. The global weighted average percentage of local recurrence was 6.7% (20 cases) and 10.9% (19 cases) after curettage and resection, respectively. No cases of metastasis were reported in the group treated with intralesional surgery, compared to five cases reported in the group treated with resection. Indications for surgery were given in most cases based on symptoms and imaging. The absence of a preoperative histological diagnosis and the lack of a scientific method to conduct the studies do not sufficiently support curettage for low-grade chondrosarcomas. In the absence of this, resection must be considered a general rule for every malignancy. In our opinion, based on the low biological growth rate of low-grade chondrosarcoma, every chondromatous lesion can be followed-up. Biopsies must be performed based on clinical and radiological suspicions such as pain, scalloping or increase in size, rather than on performing a PET scan to evidence more informative high metabolic areas.