[Histological and biological evaluation of preoperative radiotherapy on T1N0 breast carcinoma].
In order to clarify the role of radiotherapy in breast preserving surgery for early breast cancer, histological and biological effects of preoperative radiation were evaluated. Thirty-five T1N0 patients were treated by preoperative radiotherapy with beta-tron, cumulative doses of which were ranging from 25 Gy (5 Gy x 5) to 40 Gy (8 Gy x 5) and underwent subsequent modified radical mastectomy 2 or 3 weeks after the termination of radiotherapy. Clinical tumor shrinkage more than 50% was observed in 25 out of 35 cases (71%) but did not directly correlate with histological effects. Radiotherapy was basically ineffective within 25-30 Gy, whereas histological effects more than Grade 2 were gained in 8 out of 25 patients (32%), who had received 40 Gy or more. In the preoperative radiation group, there were more ER(+), PgR(+) and histologically well-differentiated cases than in the non-radiated stage I patients. Mitotic figures were also significantly reduced after radiotherapy, whereas the expression of c-erB-2 protein was unchanged between these two groups. Our data indicate the various radiosensitivity of breast cancer cells and the indication of hormone therapy for the conservative treatment of breast carcinoma.
Department of Surgery, National Cancer Center Hospital, Tokyo, Japan.
T
T
Fukutomi
H
H
Yamamoto
T
T
Nanasawa
I
I
Tsukiyama
H
H
Ogino
M
M
Itabashi
T
T
Hirota
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D016009:Chi-Square Distribution; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008875:Middle Aged; D008940:Mitotic Index / Q000528:radiation effects; D009367:Neoplasm Staging; D011300:Preoperative Care; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D011879:Radiotherapy Dosage; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012074:Remission Induction
D011518:Proto-Oncogene Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone