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Purpose/Objective(s): We have previously reported that most of axillary lymph node regions could be irradiated by the modified tangential irradiation technique (MTIT) in the IJROBP 2000 and 2004. The purpose of this study was to determine whether the use of three-dimensional conformal radiotherapy (3D-CRT) with a field-in-field technique improves dosimetry for the breast and axillary lymph nodes. Materials/Methods: Fifty patients with left-sided breast cancer were enrolled. The clinical target volume included the left breast and level I to II axillary nodes. With MTIT, we planned the radiation field size to be wider in the cranial direction than in the standard tangential fields in order to include the axillary regions. In planning with 3D-CRT, the multi-leaf collimator (MLC) was used to shape the planned target volume, using gantry angles similar to those of MTIT. Furthermore, the heart and contralateral breast were spared to the extent possible by applying the MLC manually. For hot regions receiving a dose .107% of the prescribed dose, a field-in-field technique was used to reduce dosage inhomogeneity. Dose-volume histograms were compared for the breast, axillary nodal region, heart, lung, and other normal tissues such as the skin and soft tissues. Results: There were no significant differences in the percent volume of the breast receiving more than 90% of the prescribed dose (V90) between MTIT and 3D-CRT. The mean V90 of the level I to III axillary regions were increased from 93.7%, 48.2%, and 41.3% with MTIT to 97.6%, 85.8%, and 82.8% with 3D-CRT (all p \ 0.01). The V107 of the breast and axillary region were significantly lower with 3D-CRT than with MTIT. The 3D-CRT plan significantly reduced the volume of the heart receiving more than 30 Gy (mean, 7.6 ml vs. 15.9 ml; p \ 0.01), the percent volume of the bilateral lung receiving more than 20 Gy (7.4% vs. 8.9%; p \ 0.01), and the volume of other normal tissues receiving more than 107% of the prescribed dose (0.1 ml vs. 2.9 ml; p \ 0.01). Conclusions: The use of 3D-CRT with a field-in-field technique improves regional node coverage, while decreasing doses to the heart, lungs, and the other normal tissues, as compared with MTIT.

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BACKGROUND. Breast cancer is likely to have systemic involvement. However, to the authors' knowledge there are few reports to date regarding clinically detected patterns of metastasis, meticulously studied in regard to the natural history of breast cancer, including unusual sites of metastasis. METHODS. Patients treated for invasive breast cancer from April 1983 to May 2007 were retrospectively analyzed. Patterns of clinically apparent tumor recurrence, focusing especially on unusual metastases, were studied as well as possible risk factors for unusual metastases and their influence on survival. RESULTS. Overall, 3783 patients were eligible for the current analysis. The median duration of follow‐up was 5.0 years (range, 0.6 years–20.4 years). Cumulative 5‐year and 10‐year survival rates were 89.7% and 81.5%, respectively. “Unusual metastasis” was defined as systemic failure with a frequency of ≤1%; in the current series; it was observed in 85 (2.2%) patients %. Of those, 70 (82%) had preceding metastasis in the usual sites. The median duration until the development of usual and unusual metastasis was 2.3 years and 3.6 years, respectively (P < .0001). Among764 patients with distant metastasis, the 5‐year cumulative overall survival rate in those with or without unusual metastasis was 53.5% and 53.4 years, respectively (P = .33). No risk factors for unusual metastasis were identified. CONCLUSIONS. This retrospective study examined the frequency of unusual metastases in a large number of Japanese patients with initially nonmetastatic breast cancer. The prognosis of patients with unusual metastases was found to be similar to that of patients with metastasis only at more usual sites. Cancer 2008. © 2008 American Cancer Society.

A series of new polyimides was prepared by reacting 2,6‐diaminopyridine with various aromatic dianhydrides in DMF in 1 : 1 mole ratio. All the resulting polyimides were readily soluble in organic solvents such as dimethylformamide, N,N‐dimethylacetamide, pyridine, m‐cresol, THF, etc. They also show good film‐forming ability. The polyimides exhibit good thermal stability and mechanical properties. The polymers have high Tg in the range of 252–296°C. The inherent viscosities of the polymers vary from 0.81 to 1.28 dL/g. A new class of bismaleimide and polyaspartimide as also synthesized. All the resulting polymer structures were characterized by FTIR and elemental analysis. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1846–1853, 2004