Late skin and subcutaneous soft tissue changes after 10-gy boost for breast conserving therapy.
OBJECTIVE
To evaluate the influence of boost irradiation for breast conserving therapy on skin and subcutaneous tissue.


METHODS
Between 1989 and 1995, 468 patients were treated with breast conserving surgery (quadrantectomy or wide excision with axillary dissection) followed by 50 Gy whole breast irradiation. Among them, fifty-eight patients with positive or close margins were treated with 10 Gy external beam boost irradiation. Skin and subcutaneous soft tissue changes during 5-years of follow-up were examined by inspection and palpation and evaluated using the BCT follow-up form based on EORTC late effect toxicity scoring.


RESULTS
Four percent (20/468) of the patients showed grade 2 late changes in skin and soft tissue. Four of them had skin telangiectasis, which was limited to within the boost field. Boost irradiation had no definite influence on other late changes. Patients' age, extent of surgery, and pT size had no significant relation to the late changes. The cosmetic score 5 years after BCT was not significantly different between the patients with and without boost irradiation.


CONCLUSIONS
Although 10 Gy boost irradiation after 50 Gy whole breast irradiation increased skin telangiectasis, the late skin and soft tissue changes caused by the boost irradiation were generally mild and there was no substantial deterioration of cosmetic outcome.
Department of Therapeutic Radiology and Oncology, Kyoto University, Kyoto, Japan.
Setsuko
S
Okumura
Michihide
M
Mitsumori
Masaki
M
Kokubo
Chikako
C
Yamauchi
Sachiko
S
Kawamura
Natsuo
N
Oya
Yasushi
Y
Nagata
Masahiro
M
Hiraoka
D000230:Adenocarcinoma / Q000473:pathology / Q000628:therapy*; D001943:Breast Neoplasms / Q000473:pathology / Q000628:therapy*; D003131:Combined Modality Therapy; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental / Q000379:methods*; D008875:Middle Aged; D009367:Neoplasm Staging; D011855:Radiodermatitis / Q000209:etiology* / Q000473:pathology; D011878:Radiotherapy / Q000009:adverse effects* / Q000379:methods; D040521:Subcutaneous Tissue; D013684:Telangiectasis / Q000209:etiology* / Q000473:pathology; D013997:Time Factors