Inflammatory breast cancer (IBC) and patterns of recurrence: understanding the biology of a unique disease.
BACKGROUND
Inflammatory breast cancer (IBC) is the most aggressive manifestation of primary breast cancer. The authors compared the prognostic features of IBC and non-IBC locally advanced breast cancer (LABC) to gain insight into the biology of this disease entity.


METHODS
This retrospective analysis consisted of 1071 patients, comprising 240 patients with IBC and 831 patients with non-IBC LABC who were enrolled in 10 consecutive clinical trials (5 from each disease group). All patients received similar multidisciplinary treatment. The authors measured time to disease recurrence for each individual site from the start of treatment to the date of disease recurrence or last follow-up (recurrence-free survival) and overall survival rates to the date of last follow-up or death.


RESULTS
The median follow-up period was 69 months (range, 1-367 months). Pathologically complete response rates were 13.9% and 11.7% in the IBC and non-IBC LABC groups, respectively (P = .42). The 5-year estimates of cumulative incidence of recurrence were 64.8 % and 43.4% (P < .0001), respectively, for IBC and non-IBC LABC. IBC had significantly higher cumulative incidence of locoregional recurrence and distant soft-tissue and bone disease. The 5-year overall survival (OS) rate was 40.5% for the IBC group (95% CI, 34.5%-47.4%) and 63.2% for the non-IBC LABC group (95% CI, 60.0%-66.6%; P < .0001).


CONCLUSIONS
IBC was associated with a worse prognosis and a distinctive pattern of early recurrence compared with LABC. These data suggested that investigating factors affecting "homing" of cancer cells may provide novel treatment strategies for IBC.
Cristofanilli
Massimo
M
Department of Breast Medical Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. mcristof@mdanderson.org
Valero
Vicente
V
Buzdar
Aman U
AU
Kau
Shu-Wan
SW
Broglio
Kristine R
KR
Gonzalez-Angulo
Ana Maria
AM
Sneige
Nour
N
Islam
Rabiul
R
Ueno
Naoto T
NT
Buchholz
Thomas A
TA
Singletary
Sonja E
SE
Hortobagyi
Gabriel N
GN
D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000453:epidemiology / Q000556:secondary; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology* / Q000628:therapy; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007249:Inflammation; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012983:Soft Tissue Neoplasms / Q000453:epidemiology / Q000556:secondary