Effects of Postoperative Radiotherapy on Leptomeningeal Carcinomatosis or Dural Metastasis after Resection of Brain Metastases in Breast Cancer Patients.
OBJECTIVE
In this retrospective study, we compared the incidence of leptomeningeal carcinomatosis or dural metastasis (LMCDM) in patients who received whole brain radiotherapy (WBRT), partial radiotherapy (PRT), or no radiotherapy (RT) following resection of brain metastases from breast cancer.


METHODS
Fifty-one patients with breast cancer underwent surgical resection for newly diagnosed brain metastases in two institutions between March 2001 and March 2015. Among these, 34 received postoperative WBRT (n=24) or PRT (n=10) and 17 did not.


RESULTS
With a median follow-up of 12.4 months (range, 2.3 to 83.6 months), 22/51 patients developed LMCDM at a median of 8.6 months (range, 4.8 to 51.2 months) after surgery. The 18-months LMCDM-free survival (LMCDM-FS) rates were 77.5%, 30.0%, and 13.6%, in the WBRT, PRT, and no RT groups, respectively (p=0.013). The presence of a tumor adjacent to cerebrospinal fluid flow and no systemic treatment after treatment for brain metastases were also associated with poor LMCDM-FS rate. Multivariate analysis showed that WBRT compared to PRT (p=0.009) and systemic treatment (p < 0.001) were independently associated with reduced incidence of LMCDM.


CONCLUSIONS
WBRT improved LMCDM-FS rate after resection of brain metastases compared to PRT in breast cancer patients.
Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Boram
B
Ha
Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
Seung Yeun
SY
Chung
Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Yeon-Joo
YJ
Kim
Neuro-Oncology Clinic, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Ho-Shin
HS
Gwak
Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
Jong Hee
JH
Chang
Department of Neurology, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Sang Hyun
SH
Lee
Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
In Hae
IH
Park
Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Keun Seok
KS
Lee
Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Seeyoun
S
Lee
Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Tae Hyun
TH
Kim
Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Dae Yong
DY
Kim
Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
Seok-Gu
SG
Kang
Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
Chang-Ok
CO
Suh
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis / Q000556:secondary* / Q000628:therapy*; D001943:Breast Neoplasms / Q000473:pathology*; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D055756:Meningeal Carcinomatosis / Q000175:diagnosis / Q000556:secondary* / Q000628:therapy*; D008875:Middle Aged; D011182:Postoperative Care; D011878:Radiotherapy; D018719:Erb-b2 Receptor Tyrosine Kinases; D012008:Recurrence; D012189:Retrospective Studies; D017211:Treatment Failure; D016896:Treatment Outcome
D018719:Erb-b2 Receptor Tyrosine Kinases
Breast neoplasms; Meningeal carcinomatosis; Partial radiotherapy; Whole brain radiotherapy