Describes childhood Ewing sarcoma treatment with cobalt radiation, survival and serious late effects, and…

Introduction In 1961, I was five years old and was diagnosed with Ewing’s sarcoma. The tumor, considered lethal at that time, was located in my left leg, between the tibia and fibula. I was immediately treated with cobalt radiation treatments. Chemotherapy was not available at that time. Background The treatment was done via Palm Harbor Hospital in Garden Grove, CA by Dr. John Knauer in 1961 and was considered rather experimental, since the usual approach was immediate amputation of the diseased limb. My evidence is anecdotal. Results and Analysis Since this treatment was fairly new, I received a substantial dose of cobalt radiation to my left leg, while protected with a lead sheet. After a few weeks, my leg turned dark brown and atrophied in a bent position. The brown surface skin would peel off if rubbed. My leg stopped growing. I developed a deep gaping wound where my calf used to be, which never healed and was always raw and full of pus. Several skin graft surgeries were attempted but did not take. Physical therapy was attempted, but, after two years of trying, the wound was still there and hadn't improved and my leg was still bent and hadn't grown. However, I was alive and free of cancer. After two years, the disparity between my two legs increased and the leg was amputated above the left knee. I have a short stump and x-rays show the residual femur is quite thin. Long Term Outcomes For 65 years, I have led a normal life with no further major issues and no recurrence of Ewing's sarcoma. I use an artificial leg and have some scoliosis. I hav three healthy children. At 43, I had a partial thyroidectomy due to a benign cyst. At the age of 70, I was diagnosed with a basal cell carcinoma on my collar bone. I have osteoporosis and arthritis in my spine, right hip, and right knee. X-rays reveal my pelvis is partially malformed, and my residual left femur is very thin. Late effects from that era are the same radiation injuries seen with any mega voltage therapy, often more extensive because of the beam geometry and the doses then used. Long-term follow-up of patients treated on cobalt units, and of childhood-cancer cohorts that include the cobalt years, consistently finds these late effects: • Fibrosis, atrophy, and poor wound healing in the treated field, driven by obliterating endarteritis. • Growth arrest and deformity when growing bone was in the field. A PENTEC review of childhood spine irradiation found clinically significant scoliosis after doses of about 15 Gy or more in infants, and grade 2 or higher scoliosis after 30 Gy in children irradiated at ages 2 to 6. Height loss was more common when large spinal segments were treated before puberty to more than 20 Gy. The review notes that orthovoltage and cobalt beams were worse than later techniques because of dose gradients across the vertebrae. • Second cancers in the irradiated volume, usually after a latency of 10 to 30 years or more. In Ewing sarcoma survivors, a Childhood Cancer Survivor Study analysis found a 14.3% cumulative incidence of subsequent neoplasms at 35 years (standardized incidence ratio 7.8). Breast cancer and osteosarcoma in the field were the standouts; the osteosarcoma SIR was 377. • Musculoskeletal and cardiac morbidity in the same Ewing cohorts. Relative risk of a musculoskeletal condition was 18.1 and of a cardiac condition 1.8. By 35 years, 85% had at least one chronic condition and 74% had two or more. Treatment-related death, not recurrence, became a major cause of late mortality. • A British Columbia series that specifically separated eras found patients treated on cobalt-60 units from 1960 to 1982, then on linear accelerators after 1983. Among survivors of five years or more, 77% had a late complication; musculoskeletal problems were the most common (50%), then cardiac toxicity (28%). Actuarial second-neoplasm risk was 5% at 10 years. • Organ-specific injury matching the field: A German review estimates that about 8% of second solid tumors in adult radiotherapy patients are radiation-induced, roughly 3 extra tumors per 1,000 patients at 10 years, with latency from months to decades. Recommendations I would like to see more studies on late effects of cobalt radiation and would recommend an intense educational program for the benefits of today's safer forms of radiation therapy. Conclusions In the early 60s radiation therapy dosages were experimental. More studies of late effects of cobalt radiation would add to data that could prove valuable today. A deep education of the public about benefits would counter deep public distrust. I survived a lethal form of bone cancer thanks to early detection and cobalt radiation treatment.