Breast-preserving treatment of breast carcinoma: analysis of surgical, pathologic-anatomic and radiotherapeutic data of 291 cases

• Published in: Praxis (Bern. 1994) Vol. 85; no. 1-2; p. 21
• Main Authors: Schwegler, N, Kern, T, Lazovic, N, Notter, M
• Format: Journal Article
• Language: German
• Published: Switzerland 03.01.1996
• Subjects: Adult; Aged; Aged, 80 and over; Breast Neoplasms - radiotherapy; Breast Neoplasms - surgery; Cobalt Radioisotopes - therapeutic use; Combined Modality Therapy; Female; Humans; Mastectomy, Segmental - methods; Middle Aged; Neoplasm Recurrence, Local; Radiotherapy Dosage; Radiotherapy, High-Energy
• ISSN: 1661-8157

291 breast cancer patients treated with conserving surgery and subsequent locoregional irradiation were studied. The method of surgery consisted of 200 lumpectomies, 76 quadrantectomies and 15 with either a wide excision or with an atypical resection. In at least 42.6% (124 out of 291), the tumor had been within 10 mm distance to the margin of resected specimen, in 13.4% (39 out of 291) the tumor even reached the border. In the other reports, a numerical description of the distance to the margins was not given. Postoperative radiotherapy was applied with 50 Gy cobalt-60/6-MeV photons to include the whole breast. A boost of tangentially opposed photon beams was added, replacing a technique with direct electron fields used in an earlier period during three years. The supraclavicular fossa received 46 Gy, the retrosternal pathway was covered with 45 to 50 Gy photons/electrons. Locoregional failure after an average observation time of 39.5 months was 4.5% (13 out of 291), within the target volume 3.8% (11 out of 291. The 39 cases on which the tumor reached the margin of resection, 92.3% (36 out of 39) remained free of recurrences. With a tumor-free resection line but a maximal distance of 10 mm, one recurrence (1.2% or 1 out of 85) was found. With the application of tangential photon beams to the tumor bed, which technically allowed sparing skin parts but also slightly reduced daily doses, the incidence of telangiectasis could be lowered to 2.5%. An anatomical was model was constructed to resemble a patient in the treatment position. Dosimeters were implanted and verified by computed tomography. Measurements of the radiation fields were performed within the breast, the lung and along the mammaria-interna chain. Minimal angle changes of 5 degrees decreased the retrosternal dose down with the amount of 56.5%, 10 degrees of 75% and 15 degrees of 85.7%. In contrast, moving the central axis medially by 1 cm and 2 cm increased the lung dose 2.2 and 4.4 times, respectively, whereas the dose within the breast remained almost equal. This emphasizes the importance of identical positioning, which must be realized 25 to 35 times throughout the course of therapy, often with different staff! Precision and consistent positioning are the main priorities. If these goals are achieved, lumpectomy with subsequent high-dose radiotherapy respecting cosmetics provides patients with excellent quality of life.