Bone Sarcoma in Pediatric & Adolescent Population in India
Bone Sarcoma Awareness, Limb Salvage and Challenges
Bone sarcomas are rare cancers, constituting 5-7% of all childhood malignancies. Osteosarcoma and Ewing’s Sarcoma constitute the common malignant bone cancers occurring in pediatric and adolescent age group.
Multidisciplinary sarcoma treatment involves team of specialists in field of Orthopaedic oncology (musculoskeletal oncology), Radiologist, Pathologist, Medical oncologist, Radiation oncologist, Pediatric intensivist, Pain and palliative care specialist, Cancer psychologist and Social worker.
Cure rate with Evidence based multidisciplinary approach at dedicated sarcoma centers in India ranges between 60-70 % currently. Studies have proved that outcomes are significantly better when bone sarcomas are treated at specialized sarcoma referral centers. The better outcomes are attributed to early identification, diagnosis, appropriate staging, neo adjuvant high dose chemotherapy followed by limb salvage surgery and adjuvant high dose chemotherapy and/or radiation therapy.
Today, a pediatric bone sarcoma does not have to be treated with Amputation as was the norm two decades ago. Limb salvage surgeries can be performed in nearly 95% patients at dedicated sarcoma centers in the world in which India is not ‘lagging behind’. The provision of chemotherapy has played a major role in allowing Limb Salvage. It is imperative that every pediatric patient with diagnosis of sarcoma is provided access to such facilities or centers which are supervised by sarcoma referral centers to facilitate early identification and treatment.
Awareness on bone sarcomas is limited. Attaining this end point of ‘Early identification and Appropriate Management’ is sadly not the norm due to a perceived lack of awareness in both public and professional community. This is reinforced by the high percentage of large extra compartmental bone sarcomas and metastatic bone sarcomas presenting to the Outpatient departments across the country.
Sadly, studies have shown that large tumour size and presence of metastasis at diagnosis are significant independent poor prognosticators and vice versa for small, intra compartmental sarcomas.
Limb salvage in children has its own challenges when compared to the adults. Bone sarcomas have a predilection for bones around the knee joint which is a major contributor to height of the child. The younger the child, the more the potential is for growth. Chemotherapy and Radiotherapy can result in stunting the growth to large extent. So the aim of limb salvage surgery should be to preserve as much growing ends of the bone as possible. Advances in techniques of tumour excision and reconstructive techniques over the years are helping to achieve the same. Adolescents nearing maturity can now be fitted with adult version of tumour endoprosthesis whereas children require implantation of a ‘Growing’ tumour endoprosthesis (manual or magnetic).
It is also possible to save the physis and reconstruct the defect by biological means, with help of bone grafts from bone bank (Massive bone allografts), utilizing the child’s fibula (live fibula) or even re-implanting the tumour bone treated with radiation (Extracorporeal Radiation and Reimplantation) or liquid nitrogen (Cryotherapy). These complex biological limb salvage procedures are also being performed in bone sarcomas around pelvis and extremities providing adequate oncological clearance and good functional results.
Another advantage of pursuing a biological solution in both limbs and pelvis in pediatric population is that the procedure is definitive, permanent and there is little need for revision surgeries in future.
In some situations where Salvage with tumour endoprosthesis or biological means is not feasible, another modified Limb Salvage procedure- Rotationplasty is performed. Rotationplasty involves resecting the bone sarcoma and reattaching the distal Limb high up after rotation. This procedure enables the ankle to perform as a knee in its new rotated position and such patients can be fitted with prosthetics enabling them to even partake in sports and other high demand activities.
Multimodal therapy for bone sarcomas are not without relapses or complications. It’s is necessary to educate the parents and guardians regarding the risk of local or distant relapse (metastasis to lungs is common) and need for surveillance at regular intervals. They are educated about the risk of developing secondary malignancies such as leukemias- lymphomas due to chemotherapy, radiation induced sarcomas due to radiotherapy over long term in addition to infertility, cardiotoxicity, ototoxicity and neurotoxicity.
The end result of treatment of any cancer should be ability to perform daily activities of living and reintegration into society. Social workers, Foundations, NGO’s, Cancer Psychologists and Rehabilitation specialists play an integral role in assisting the child and family throughout treatment process and later to improve bone sarcoma awareness.
The need of the hour is to promote the notion that bone sarcoma is treatable and curable in public domain. This will encourage children and parents to get evaluated at any level at an early stage. It is also necessary to involve Pediatricians, Physicians, General surgeons, Orthopaedic surgeons and other Medical professionals in appropriate platforms to impart the need for early identification and prompt referral. Part of this work is already in process in grass roots as part of resident training programme, seminars at multidisciplinary conferences.
Another initiative to encourage more professionals is a platform called ‘Bone Tumour Forum’ where such scenarios are discussed regularly for Bone sarcoma awareness.
Dr Srimanth B S