Radiologic follow‐up of untreated enchondroma and atypical cartilaginous tumors in the long bones

Abstract

Background and ObjectivesBoth enchondroma and atypical cartilaginous tumors (ACT) are not considered malignant, so inactive and asymptomatic tumors might not need surgery. To the best of our knowledge, this is the first study that has been done to evaluate the natural course of conservative‐treated enchondroma and ACT in the long bones.MethodsFor this retrospective study, we analyzed the results of patients in whom we refrained from surgery and only regularly performed radiological follow‐up of the tumor. Minimal follow‐up after initial diagnosis was 24 months.ResultsForty‐nine patients were included in this study. Eight out of forty‐nine cases received surgical treatment during follow‐up of the tumor. The reasons for this surgery were radiologic growth of the tumor in two cases, pain in one case, patient request in three cases, another indication for surgery in the same limb in two cases.ConclusionIn this small series of conservatively treated enchondroma and ACT, only 6% of the patients had a medical indication for surgery. This study shows that indication for surgery should be discussed more thoroughly. Based on our results, we would recommend annual radiologic follow‐up for asymptomatic enchondroma or ACT in the long bones, irrespective of tumor size. J. Surg. Oncol. 2016;114:987–991. © 2016 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc.

Chondroid Tumors as Incidental Findings and Differential Diagnosis between Enchondromas and Low-grade Chondrosarcomas

“…In 49 patients with conservatively treated ECs and ACTs of long bones, implementing follow-up imaging with radiographs and MRI, Deckers et al noticed that only 6% of the patients underwent surgical treatment during follow-up (due to invalidating pain or radiologic growth). 3 None of the surgically treated lesions had transformed into a higher grade CS, suggesting that surgery indication should be evaluated more scrupulously. Furthermore, the duration of follow-up time before surgery had no impact on the procedure itself or on the patient's rehabilitation.…”

“…Evidence shows that $ 4% of solitary ESs can change into CSs, and a small subset of ECs may regress while most of these lesions will remain unchanged, highlighting the need for follow-up. 3,7 Radiographic follow-up instead of surgery may prevent overtreatment, resulting in less morbidity and lesser costs. We recommend that every chondroid lesion characterized by the absence of imaging and clinical signs of malignancy in a long bone should have planned interval follow-up.…”

“…4,6,7 ACTs (or grade 1 CSs) are benign but predominantly locally aggressive tumors that rarely metastasize and have an excellent prognosis (5-year survival of 83-99%). 3 Histologically, these tumors are moderately cellular, show myxoid change and mild nuclear atypia with binucleate forms, and, more importantly, they do not show permeative growth. In some centers, it is equivalent to the term "grade 0.5 CS," "borderline CS," or "cartilaginous lesion of unknown malignant potential (CLUMP)," but these terms are not listed in the WHO classification and should be avoided.…”

CORR Insights®: Do Orthopaedic Oncologists Agree on the Diagnosis and Treatment of Cartilage Tumors of the Appendicular Skeleton?

“…In a recent natural history study of these tumors, Deckers and colleagues [2] found that only 6% of their patients with hyaline cartilage tumors required operation for ''medical reasons'' (tumor growth or unexplained pain). Why are so many of these lesions in need of biopsy?…”

“…Only a small percentage of long bone hyaline cartilage tumors require surgery [2]. If we could agree to use behavior as the gold standard, the key in developing a standardized approach to these tumors would then be to develop a nomogram based on clinical and radiologic criteria.…”