Benefits versus risks in conservation surgery with irradiation for breast cancer

Radiation-induced cancer as a factor in clinical decision making (the 1989 ASTRO Gold Medal address)

1. Ionizing radiations are weak carcinogens. Under certain conditions they can induce cancers in experimental animals and humans. 2. This potential carcinogenicity has been a deterrent to the use of radiation therapy despite its many advantages in the management of patients with cancers. 3. In a range of clinical situations, such as the irradiation of cancers arising in the head and neck, breast, prostate and skin, an increase of second cancers can not be detected above the natural frequency of additional cancers. In the curative treatment of patients with Hodgkins disease, ionizing radiations are not associated with an increased frequency of leukemias and induced second tumors are no more frequent than following the use of alkylating agents. 4. All second tumors attributed to radiation therapy occur after a latent period of many years and except for leukemia usually are potentially curable. 5. The risks of radiation-induced second cancers are no greater than the risks of operative or anesthetic deaths and these catastrophes are immediate and non-remedial. 6. Therefore, at this time, the potential of radiation-induced cancers should not be a factor in the selection of treatment for patients with cancer.

Nuclear characteristics as indicators of prognosis in node negative breast cancer patients

Nine clinical, biologic and histologic variables were evaluated for their significance in predicting the metastasis free survival (MFS) and the overall survival (OS) of 650 histologic node negative breast cancer patients. The variables studied were: menopausal status, UICC clinical stage of disease, Scarff-Bloom and Richardson (SBR) grade and its 3 components, estrogen and progesterone receptors, and anatomic tumor size. Multivariate Cox analyses revealed that histologic grade and clinical stage were the only significant prognostic factors for both MFS and OS. In the SBR grading system, grades I and III clearly have defined those patients with low and high risk for relapse, respectively. However, it is well known that more than 50% of the patients fall into the intermediate risk category, grade II, which provides essentially no useful prognostic information for those patients. To improve the assignment of patients to specific risk groups, a modified grade (MSBR), with five categories ordered according to the degree of malignancy, has been built from the nuclear pleomorphism and the mitotic index of the SBR grade. In combination with clinical stage, MSBR was found to be a prognostic indicator with high discriminatory power and caused the SBR grade to lose its significance. The first three categories of this MSBR may be gathered to designate low risk patients, whereas the last two categories, once combined, contain all the SBR grade III plus 57% of the SBR grade II tumors, and reliably identify high risk node negative patients. We suggest that a systemic adjuvant therapy should be discussed in this high risk group.

Risk of contralateral breast cancer. Associations with histologic, clinical, and therapeutic factors

A case-control study was conducted to assess the risk factors associated with the development of a contralateral primary breast cancer among women who had had a first primary breast cancer. Hospital records were reviewed for 292 women with an incident contralateral breast cancer, diagnosed in one of eight hospitals between July 1, 1975 and December 31, 1983, and for a comparison group of 264 surviving unilateral breast cancer patients, previously diagnosed in the same hospitals. All subjects were identified through the records of the Connecticut Tumor Registry. Having an initial tumor containing lobular carcinoma was associated with an almost twofold increased risk of developing a contralateral cancer (aOR = 1.8; 95% CI: 1.0-3.5). Among those for whom a progesterone receptor assay was available, a positive assay was associated with an increased risk of a contralateral primary (aOR = 3.2; 95% CI: 1.0-9.5). AB blood type was also associated with an elevated risk, but this elevation was not statistically significant (aOR = 2.3; 95% CI: 0.7-7.7). Having received radiation treatment was not significantly associated with the risk of a contralateral primary (aOR = 0.9; 95% CI: 0.6-1.4), whereas chemotherapy treatment was associated with a significantly lowered risk (aOR = 0.3; 95% CI: 0.1-0.7). The association with chemotherapy appeared to be modified by body build (ROR = 1.5; 95% CI: 1.0-2.3 for a 2.5-unit differential in Quetelet's index).