Importance of radiation therapy for breast cancer patients treated with high-dose chemotherapy and stem cell transplant.
OBJECTIVE
To determine local-regional failure rates in breast cancer patients treated with surgery and high-dose chemotherapy with stem cell transplant and to relate local-regional failure to the use and timing of radiation treatment.


METHODS
We retrospectively reviewed the records of 165 breast cancer patients treated on institutional protocols with surgery and high-dose chemotherapy with stem cell transplant. All patients had either Stage III disease, 10 or more positive axillary lymph nodes, or 4 or more positive axillary lymph nodes following neoadjuvant chemotherapy. Twelve patients had inflammatory breast cancer. Thirteen patients treated with breast preservation and 5 patients who died from toxicity within 30 days of transplant were excluded from the analyses of local-regional recurrences. In the remaining 147 patients, 108 were treated with adjuvant radiation and 39 were not. The disease stage distribution for these two groups was comparable. The median follow-up for surviving patients was 35 months.


RESULTS
The 3- and 5-year actuarial disease-free survival (DFS) for the entire group was 60% and 51%, respectively. The 5-year rates of freedom from isolated local-regional recurrence were 95% in the patients treated with adjuvant radiation and 86% in the patients who did not receive radiation (p = 0.014, log rank comparison). The 5-year rates of any local-regional recurrence as a first event (isolated recurrences plus those with simultaneous local-regional and distant recurrences) were 92% versus 82%, respectively for patients whose treatment did and did not include radiation (p = 0.038). We could not demonstrate a correlation of the timing of radiation with the risk of local-regional recurrence.


CONCLUSIONS
These data indicate that high-dose chemotherapy does not negate the importance of radiation in optimizing local-regional control in patients with high-risk breast cancer. Given the results of recent randomized trials studying postmastectomy radiation, which show that improving local-regional control improves overall survival (OS), we believe that all breast cancer patients with high-risk primary breast cancer who are treated with high-dose chemotherapy with stem cell transplant should receive radiation as a component of their treatment.
Buchholz
T A
TA
Department of Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA. tbuchhol@notes.mdacc.tmc.edu
Tucker
S L
SL
Moore
R A
RA
McNeese
M D
MD
Strom
E A
EA
Jhingrin
A
A
Hortobagyi
G N
GN
Singletary
S E
SE
Champlin
R E
RE
D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000532:radiotherapy*; D003131:Combined Modality Therapy; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008408:Mastectomy; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000737:chemistry / Q000517:prevention & control*; D009367:Neoplasm Staging; D012189:Retrospective Studies; D016019:Survival Analysis