Biomedical subjects
Publications and source records attributed to E Grimaud.
A true three-dimensional algorithm has been developed at the Gustave Roussy Institute, which can evaluate the dose distribution in inhomogeneous media. In this paper, an explanation is given that, in our view, problems of inhomogeneity cannot be solved without accounting for the third dimension and its contribution to scattered dose calculation.
Between 1954 and 1983, 7620 patients were treated for breast carcinoma at Institut Gustave Roussy (France). Of these patients, 6919 were followed for at least 1 year. Out of these, 11 presented with sarcomas thought to be induced by irradiation, 2 of which were Steward-Treves Syndrome, and 9 of which were sarcomas within the irradiated fields. All histological slides were reviewed and a comparison with those of breast cancer was done. The sites of these sarcomas were: parietal wall, 1 case; second costal cartilage, 1 case; infraclavicular region, 1 case; supraclavicular region, 2 cases; internal third of the clavicle, 2 cases; axillary region 2 cases; and the internal side of the upper arm (Stewart-Treves syndrome), 2 cases. The median age of these 11 patients at the diagnosis of sarcomas was 65.8 (49-83). The mean latent period was 9.5 years (4-24). Three patients underwent radical mastectomy and nine modified radical mastectomy. Only one patient received chemotherapy. The radiation doses received at the site of the sarcoma were 45 Gy/18 fr. for 10 cases and 90-100 Gy for 1 case (due to overlapping between two fields). The histology was as follows: malignant fibrous histiocytoma, 5 cases; fibrosarcoma, 3 cases; lymphangiosarcoma, 2 cases; and osteochondrosarcoma, 1 case. The median survival following diagnosis of sarcoma was 2.4 years (4 months-9 years). Two patients are still alive: one with recurrence of her breast cancer, the other in complete remission, with 7 and 3 years follow-up, respectively. All other patients died from their sarcomas. The cumulative incidence of sarcoma following irradiation of breast cancer was 0.2% (0.09-0.47) at 10 years. The standardized incidence ratio (SIR) of sarcoma (observed n# of cases (Obs)/expected n# of cases (Exp) computed from the Danish Cancer Registry for the same period) was 1.81 (CI 0.91-3.23). This is significantly higher than one, with a p = 0.03 (One Tailed Exact Test). The mean annual excess (Obs-Exp)/100.000 person-years at risk during the same period/(100,000) was 9.92. This study suggests that patients treated by radiation for breast cancer have a risk of subsequent sarcomas that is higher than the general population. However, the benefit from adjuvant radiation therapy in the treatment of breast cancer exceeds the risk of second cancer; therefore, the potential of radiation-induced sarcomas should not be a factor in the selection of treatment for patients with breast cancer.
BACKGROUND: The thyroid gland is among the most radiosensitive organs. However, little is known about the long-term risk of developing a thyroid tumor after fractionated external radiotherapy for cancer during childhood. OBJECTIVE: To study the long-term risk of developing a thyroid tumor in 4096 three-year survivors of childhood cancer treated between May 1942 and December 1985 in 8 centers in France and the United Kingdom, 2827 of whom had received external radiotherapy. METHODS: A wide range of radiation doses were given to the thyroid: 1164 children received less than 0.5 Gy and 812 received more than 5.0 Gy, the average dose being 7.0 Gy. RESULTS: After mean follow-up of 15 years (range, 3-45 years), 14 patients-all of whom had received radiotherapy-developed a clinical thyroid carcinoma. Within the cohort, the relation between radiation dose to the thyroid and risk of thyroid carcinoma and adenoma was similar to that observed in patients who received radiotherapy during childhood for other reasons, such as an excess relative risk per gray of 4 to 8, up to a few gray. In contrast, compared with thyroid cancer incidence in the general population, the standardized incidence of thyroid carcinoma was much higher than expected from the dose-response relationship estimated within the cohort and from patients who received radiotherapy during childhood for other reasons: a dose of 0.5 Gy was associated with a standardized incidence ratio of 35 (90% confidence interval, 10-87) and a dose of 3.6 Gy with a standardized incidence ratio of 73 (90% confidence interval, 28-153). We did not show a reduction in excess relative risk per gray with use of an increasing number of fractions. CONCLUSION: Although we cannot estimate the exact proportion, it is probable that some or all children who are treated for cancer are predisposed to developing a thyroid carcinoma.