What is Extracorporeal radiation and reimplantation(ECRT)
Extracorporeal radiation and reimplantation (ECRT) is a type of limb salvage surgery, performed in individuals suffering with bone sarcoma. ECRT is an established form of biological salvage method where the cancer affected bone is sterilised with high dose radiation, thereby effectively killing the cancer cells. This treated bone when reimplanted into the defect with plate and screws, will act like a bone graft (devoid of cancer cells) and is incorporated by the body gradually over time.
Indications for ECRT
ECRT is indicated in treatment of Bone sarcomas such as Osteosarcoma, Ewing’s sarcoma, Chondrosarcoma and Adamantinoma.
Bone sarcomas involving the shaft(diaphysis) of the long bones, such as femur, tibia, humerus, radius, ulna etc.
Bone sarcomas involving the flat bones, such as pelvis, scapula, clavicle etc.
Paediatric and Young Adults age group
As a component of Graft-Prosthesis-Composite Reconstruction
What are the tests done before ECRT
Blood tests to assess haemoglobin levels, blood group and rule out infection
Imaging tests in form of X-rays, CT scan, MRI of involved limb. A PET CT scan will be done to stage the bone sarcoma
How is ECRT done?
The tumour bone is dissected with a surrounding margin of healthy tissues
The tumour bone is removed or cut based on preoperative calculations done with help of X-rays, CT scan, MRI and 3D models. Computer assisted navigation is also utilised in complex situations.
Samples are sent to assess response to chemotherapy and the tumour bone is subjected to high dose radiation in sterile environment.
This “Cancer free” bone graft is treated with solvents and implanted into the bony defect with help of plates and screws.
Advantages of ECRT
ECRT utilises the individual’s own bone stock to reconstruct the defect after removal of tumour bone segment instead of tumour prosthesis. There is no risk of rejection.
Benefits the paediatric age group where the growing ends of the bone need to be preserved to allow natural growth and increase in height.
It does not need repeated or revision surgeries in the future, as is the case with tumour prosthesis. It provides a future bone stock for treatment of any complications.
It is similar to usage of massive bone allografts(when available), which is expensive and not easily available.
It is an economically viable reconstructive option for limb salvage surgery.
What are the complications associated with ECRT procedure?
The complications associated with ECRT procedure is similar to other biological limb salvage surgeries, as follows:
Delayed healing or incorporation of ECRT graft, Nonunion and fracture of ECRT graft
Local recurrence and tumour progression
Clotting of Blood in deep veins, Deep vein thrombosis
What is the aftercare?
Individuals after limb salvage surgery by ECRT can go home after few days of hospital stay. Physiotherapy will commence from the next day of surgery, this improves confidence and increases compliance to further treatment. Due to the nature of biological reconstruction, the individual will not be allowed to place weight on the operated limb until signs of healing is seen on imaging tests such as X-ray and CT scan.
Comprehensive Cancer Centre