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    Treatment Recommendations for Chondrosarcomas of the Pelvis

    A recently published study suggests that surgery with wide resection margins is the preferred option for managing conventional primary central chondrosarcoma of the pelvis, regardless of lesion grade.

    Authors

    Timothy Rapp, MD, and Mathew J. Hamula, MD

    Article

    Bus MPA, Campanacci DA, Albergo JI, Leithner A, van de Sande MAJ, Gaston CL, Caff G, Mettelsiefen J, Capanna R, Tunn PU, Jeys LM, Dijkstra PDS. Conventional primary central chondrosarcoma of the pelvis: prognostic factors and outcome of surgical treatment in 162 patients. JBJS Am. 2018 Feb 21;100(4):316-325.

    Background

    Chondrosarcomas are among the most frequently encountered primary tumors of the bone in adults, and most (up to 80%) are the conventional primary central subtype. They are commonly found in the pelvis and are histologically graded according to differentiation. Conventional primary central subtype chondrosarcomas are more likely to be high-grade and appear to have a worse prognosis than secondary peripheral lesions.

    Surgical resection remains the mainstay of treatment for chondrosarcomas, particularly of the pelvis, due to their relative resistance to radiation and chemotherapy. Historically, pelvic bone tumors were treated with hindquarter amputation. Currently, standard of care involves limb-salvaging en block resection, also known as internal hemipelvectomy, when feasible. This, however, presents a significant challenge due to:

    • Relatively complex pelvic anatomy
    • Nearby vital neurovascular structures
    • Often large size of tumor burden at the time of diagnosis
    • Challenges associated with reconstruction.

    For these reasons there is a clinically substantial risk of contaminated margins with resection.

    Three types of margins can be used when resecting chondrosarcoma with an internal hemipelvectomy: wide, marginal, and intra-lesional.

    • Wide surgical margins involve resection outside of the reactive zone.
    • Marginal resection is through the reactive zone, with no identifiable tumor cells at the margins.
    • Intra-lesional surgical margins show evidence of tumor cells at the margins.

    Contaminated resections – ie, those resections in which tumor spillage occurred – are usually considered intra-lesional.

    Summary and Clinical Relevance

    Chondrosarcomas typically present in the fifth through eighth decades of life, with a slight male predominance. They are most commonly found in flat bones such as the pelvis or scapula. Pelvic chondrosarcomas can also involve the proximal femur. Approximately 85% of chondrosarcomas are low grade, with a risk of developing into high grade or de-differentiated chondrosarcomas. Advanced imaging such as CT or MRI can further determine cortical destruction and marrow and soft tissue involvement. Bone scans typically show increased activity in all chondrosarcoma grades.

    Histologically, low-grade chondrosarcomas demonstrate enlarged chondrocytes with plump multinucleated lacunae and few mitotic figures. In addition, the presence of abundant bland hyaline cartilage matrix can indicate a lower grade. High-grade chondrosarcomas, conversely, show abundant mitotic figures and a more mucomyxoid matrix or hypercellular cartilaginous stroma that permeates the bone trabeculae.

    Although intra-lesional curettage has been advocated by some surgeons for grade-I lesions, most surgeons advocate for wide excision of all chondrosarcomas irrespective of grade if the lesion is located in the pelvis. Historically, chondrosarcoma has been proposed to have molecular mechanisms, explaining its resistant nature to modern chemotherapy or radiation therapy. [1]

    No current studies have examined disease-specific survival after surgical intervention specifically for conventional primary central subtype chondrosarcomas of the pelvis. Previous series, including secondary peripheral chondrosarcomas, have shown 20% to 36% mortality. This is misleading for primary central lesions, however, as they appear to have a worse prognosis than secondary peripheral tumors. [2-3]

    In a recently published multi-center retrospective review, Bus et al showed a 34% rate of mortality from conventional primary central subtype chondrosarcomas. Tumor grade is the most important prognostic factor. In their series, only 1 patient with a grade-I lesion died (3%), whereas mortality rates were 33% for grade-II lesions and 54% for grade-III lesions. Tumor grade was also associated with risk of recurrence. Four of 62 patients with a recurrence had higher-grade lesions than the original grading of the tumor.

    There was no significant difference in the disease-specific survival rate after marginal and intra-lesional resection. Wide surgical margins, however, conferred a significant survival advantage.

    Tumor size was the third most-important prognostic factor: For each centimeter of increase in maximal tumor size, the risk of disease-related death increased by 8%.

    Currently, recommendations for pelvic chondrosarcoma treatment include wide excision with en bloc resection. Although questions exist regarding limited surgical procedures such as curettage and grafting for low-grade chondrosarcomas of the pelvis, most surgeons continue to advocate wide surgical margins for all pelvic chondrosarcomas irrespective of grade.

    Author Information

    Timothy Rapp, MD, is an Associate Professor of Orthopedic Surgery and Chief of the Division of Orthopedic Oncology, at NYU Langone Orthopedic Hospital, New York, New York. Mathew J. Hamula, MD, is an orthopedic surgery resident at NYU Langone Orthopedic Hospital, New York, New York.

    Disclosures

    The authors have no disclosures relevant to this article.

    References

    1. Springfield DS, Gebhardt MC, McGuire MH. Chondrosarcoma: a review. Instr Course Lect. 1996;45:417-24.
    2. Mavrogenis AF, Angelini A, Drago G, Merlino B, Ruggieri P. Survival analysis of patients with chondrosarcomas of the pelvis. J Surg Oncol. 2013 Jul;108(1):19-27. Epub 2013 May 16.
    3. Sheth DS, Yasko AW, Johnson ME, Ayala AG, Murray JA, Romsdahl MM. Chondrosarcoma of the pelvis. Prognostic factors for 67 patients treated with definitive surgery. Cancer. 1996 Aug 15;78(4):745-50.