Limb Salvage Surgery with Megaprosthesis in a Young Adult with Osteosarcoma
Osteosarcoma is a relatively rare primary malignant tumour of the bone with an estimated global incidence of 3.4 cases per million population. Although osteosarcoma is rare in the overall population, it is the most common bone cancer in children and young adults. Conventional osteosarcoma comprises about 80% of all osteosarcoma cases and usually affects young adults with peak incidence age of 10-30 years; it is more common in men than in women.
The past century has seen an improvement in survival rates with life expectancy rising from a mere 20% in the early part of the 20th century to about 65% in the recent years. The current management of osteosarcoma in early stages of the disease focuses on chemotherapy and limb salvage.
Case Study
A 20-year-old male presented to Medanta - Lucknow with complaints of swelling in distal part of the left thigh over the past 1 month. Examination revealed tenderness; overlying skin was normal in appearance and touch. Neurological examination was normal without any signs of muscle wasting; there was normal range of movement at the knee joint.
Patient underwent radiography, which was suggestive of conventional osteosarcoma. This test was followed by a biopsy and histopathological examination of the lesion that confirmed the diagnosis.
The case was discussed and the patient was planned for neo-adjuvant therapy to shrink the lesion before doing the limb salvage surgery and then adjuvant chemotherapy.
After counselling and giving his consent, the patient underwent a limb salvage surgery post completion of neo-adjuvant therapy. The goal of surgical management of osteosarcoma is complete excision of the lesion, which typically involves resection with wide margins. This is achieved in two steps – initial resection and subsequent reconstruction.
A local wide excision of the tumour margin was done using the extensile para patellar approach incorporating the biopsy tract; there was no involvement of the neurovascular bundle. Excision was followed by metallic reconstruction using distal femur megaprosthesis.
The surgery was successful with good clinical outcome. On Day 2 after the surgery, the patient was made to stand with support and was able to achieve assisted flexion of
90 degrees at the knee joint. The patient was discharged on Day 5 of the surgery and is being followed up in the OPD. The adjuvant chemotherapy session will be started soon after sutures are removed on post operative Day 15.
Discussion
As osteosarcoma is the most common primary osseous malignancy in the paediatric population, surgery presents a unique set of challenges. To achieve clear margins, excision may necessitate physeal resection that may cause growth disturbances as the child matures. In the past, a tumour that traversed the growth plate was considered to be an indication for amputation because there was no available means to restore function. With the advent of options that “grow” or expand with the patient, masses that cross the growth plate are no longer considered a contraindication to limb salvage.
Management of osteosarcoma requires a multidisciplinary team. Patients with suspected or confirmed osteosarcoma should be evaluated and treated at a comprehensive cancer care centre with a multidisciplinary sarcoma programme that includes paediatric, medical and radiation oncologists, orthopaedic and surgical oncologists, musculoskeletal pathologists, and radiologists. Successful treatment involves proper diagnosis, neoadjuvant and adjuvant multi-agent chemotherapy, and aggressive surgery with an emphasis on limb-preserving procedures.
The comprehensive cancer care programme at Medanta - Lucknow is backed by one of the largest teams of cancer doctors in the state. It is equipped to deliver advanced cancer treatments using the very best and latest in technology.
