Level of axillary involvement by lymph node metastases from breast cancer is not an independent predictor of survival.

We examined the relationship of axillary level of lymph node metastases from clinical stage I and II breast cancer to overall survival and disease-free survival rates in 135 patients who underwent complete axillary lymph node dissection to determine if anatomic level of axillary involvement (I vs II vs III) is an independent prognostic factor. All patients underwent either modified radical mastectomy or lumpectomy with axillary dissection and whole breast radiotherapy for breast cancer. Median follow-up was 6.9 years. We found no difference in overall survival or disease-free survival between patients whose highest or only level of axillary involvement was level I compared with patients whose highest or only level was II. Although patients whose highest level of nodal involvement was III had significantly worse overall survival and disease-free survival rates than patients whose highest nodal involvement was I or II, when patients were stratified by the total number of positive nodes (one to three vs four or more), there was no difference in overall survival or disease-free survival rates between levels I, II, and III. These findings indicate that the level of axillary involvement for stage II breast cancer is not of independent prognostic significance.

Radiobiology and clinical application of halogenated pyrimidine radiosensitizers.

Halogenated pyrimidines (HP) represent a unique class of non-hypoxic cell radiosensitizers currently under clinical re-investigation. In order for halogenated pyrimidines to sensitize cells to radiation, they must be incorporated into cellular DNA. In the case of human tumors, which have in general rather long cell cycle times, this may require many days of continuous drug infusion to achieve adequate replacement of the DNA base thymidine with HP. In vitro studies support the relationship between the extent of radiosensitization and the percentage of thymidine replacement. Recent clinical studies evaluating the role of iododeoxyuridine (IdUrd) as a radiation sensitizer in large unresectable sarcomas have been extremely encouraging. To support and expand upon these positive clinical findings more information and research is needed regarding: (1) the mechanism of HP-induced radiosensitization; (2) the percentage of HP thymidine replacement in human tumors achievable and how it relates to treatment outcome; (3) the means of increasing HP incorporation in tumor and minimizing incorporation in normal tissues; (4) a better understanding of optimal timing between HP administration and radiation treatment; and (5) methods to evaluate which tumors are appropriate candidates for HP therapy. While presently limited to use in conventional high dose-rate X-ray therapy, laboratory studies suggest that HP might also be effective in low dose-rate brachytherapy and for selected high LET clinical beams. HPs probably will not be 'general' non-hypoxic cell radiosensitizers for all tumor types, but with appropriate tumor-type/anatomical site selection and refinement in their administration, HPs may prove beneficial in cancer treatment.

Low-grade astrocytomas: treatment results and prognostic variables.

Low-grade astrocytomas in adults are uncommon malignant neoplasms of the central nervous system which are fatal in the great majority of patients despite a lack of aggressive histologic features. Several series of such patients have been previously reported, but prognostic factors have not been fully identified. Between 1960 and 1986, 50 patients with low-grade astrocytomas have been treated with megavoltage radiation at the Naval Hospital, Bethesda, MD, following surgical biopsy or excision. Overall actuarial survival at 10 years for the entire treated group was 32%, similar to other series. The most significant prognostic factor was patient age, with decreasing survival for each age decade and a highly significant difference in survival between patients less than age 40 compared to older patients (p = .0017). The era of treatment (before or after 1978) was also an important prognostic indicator (p = .057), largely due to an effect of dose, although better tumor localization in the CT era may also have played a role. There was a trend toward increasing survival with increasing dose of radiation, although not reaching statistical significance at the p = .05 level on multivariate analysis. Patient sex, extent of surgical resection, use of whole brain irradiation, and tumor grade did not significantly affect survival. In comparison, in a separate group of 10 patients who received surgery without radiation during the same period, all patients who were completely resected were long-term survivors, whereas none of those with incomplete resections survived longer than 6 years.

Treatment of bladder cancer with interstitial iridium-192 implantation and external beam irradiation.

Although interstitial implantation of invasive carcinoma of the bladder has been shown to be an effective treatment in Europe, there has been little experience with this method in the U.S. During the past 6 years, 14 patients at the Hospital of the University of Pennsylvania with single bladder tumors less than 5 cm and no evidence of carcinoma in situ on random bladder biopsies have been treated by a combination of external beam radiation and iridium wire implant. The iridium wire is inserted by an afterloading technique following tumor exposure via suprapubic cystotomy. Following delivery of the prescribed dose, the sources are removed percutaneously. Three patients with recurrent or high grade T1 lesions and 11 patients with T2-T3A lesions have been treated. With a median follow-up of 22 months (range 17 to 65 months), 9 patients are currently NED, 4 patients have died of disease, and 1 patient has died of intercurrent disease. There have been two isolated bladder recurrences, both non-invasive, one having been treated with cystectomy and one being treated locally. In addition, one patient developed regional failure, two developed distant metastases only, and one developed local recurrence following distant failure. The 2-year actuarial local control rate is 84%, with an overall 2-year actuarial survival of 66%. Complications have been minimal. Bladder implantation by this method is technically simple and produces excellent local control with acceptable morbidity.