title: Breast-Concerving Surgery Following Preoperative Radiotherapy to the Primary Breast Cancer of 3 cm or Larger: Histological Analysis of Size Reduction of the Tumors by Radiotherapy.
abstract: Fifteen women with primary breast cancer of 3 cm or larger were treated by radiotherapy of 5000 or 5100 cGy preoperatively for breast conservation. Among them, three responded completely to radiotherapy clinically, 6 did partially, and 6 showed minor response. Breast-concerving surgery was performed in all cases. Histologically one patient did not have cancer cells at surgery, while eight showed good response but had residual tumor, and the rest responded moderately. The histological margins were positive in six cases, of those three were positive due to an invasive component. Calculation of the size reduction of the primary tumor by radiotherapy at a histological level revealed that the invasive area of the tumors was 79.5% on average. There was a tendency, among well responding patients, to show a large reduction in size. However, the tumor cells tended to remain in the peripheral areas of the originally invasive areas. In summary, preoperative radiotherapy made the size of the primary tumors smaller in the majority of the cases clinically but the actual histological size reduction was relatively small in general. We conclude that preoperative radiotherapy is effective to extend the indications of conservative treatment in patients with a large primary breast cancer. However, care is required when we treat patients with a very large primary breast cancer conservatively.
authors.affiliation: Shikoku Cancer Center Hospital, 13 Horinouchi, Matsuyama 790, Japan.
authors.initials: S
authors.lastname: Ohsumi
authors.initials: S
authors.lastname: Takashima
authors.initials: T
authors.lastname: Saeki
authors.initials: M
authors.lastname: Kataoka
authors.initials: K
authors.lastname: Mandai