Nathalia Botero
BIOL-1615-010-F15
The Effect of Young Age in Hormone Receptor Positive Breast Cancer
Breast cancer is a malignant tumor that starts in the cells of the breast. A
malignant tumor is a group of cancer cells that can grow into (invade) surrounding
tissues or spread (metastasize) to distant areas of the body. Over the last few decades
there has been an escalation of new cases of breast cancer even in young women. It is
the leading cancer related death in women.
Studies have shown that young breast cancer patients have more advanced
disease and worse survival compared to older patients. Reports have found that breast
cancer in young women is associated with advanced stage of disease and unfavorable
tumor characteristics frequently attributed to the higher frequency of more aggressive
subtypes of cancer.
The objective was to determine disease characteristics and survival in the
subset of young women with hormone receptor positive (HR+) and HER2 negative
(HER2-) cancer.
This was a study done by David Geffen School of Medicine in Los Angeles,
California, Revlon/UCLA breast cancer center in Los Angeles and The University of
California. Where they performed a retrospective review of women with HR+/HER2breast cancer who were treated at their breast cancer center between 2002 and 2010 .
Patients were separated into two groups based on their age. First group women 40
years and younger and second group women 40 years and older.
Nathalia Botero
BIOL-1615-010-F15
All patients underwent surgical management. Pathological variables included
receptor status, Her2/neu status, Ki-67, histological grade, modified Bloom and
Richardson score and differentiation and lymphovascular invasion. P values for
comparing continuous or ordinal variable across groups were computed using the
Kruska-Wallis test. Categorical variables were compared using Fisher’s test. Survival
probabilities were estimated using the Kaplan-Meier method. Survival curves were
compared using the Log rank test. Statistical analysis were conducted using SAS
version.
Of 669 HR+/HER2- breast cancer cases, 54 (8.1%) patients were 40 years or
younger. Younger patients had more Luminal B subtype, high grade, poor differentiation,
and increased lymphovascular invasion. Younger women were treated more often with
mastectomy and adjuvant chemotherapy. Although the unadjusted recurrence - free
survival at median 55 month follow up was lower in younger women, adjusting for stage,
there was no significant difference (90.7% Versus 89.3%, p=0.74) between groups.
Young patients with HR+/HER2- type had more advanced disease with less favorable
histopathologic features. Women 40 years and younger were more likely to have high
grade, poorly differentiated tumors and lymphovascular invasion. More younger women
also had higher stage of disease which made them more likely to undergo more
aggressive breast cancer surgery.
This study came with the conclusion that younger patients with HR+/HER2breast cancer have a more developed disease and their treatment is more aggressive
than older patients. There were many adverse characteristics of the tumors associated
Nathalia Botero
BIOL-1615-010-F15
with the younger patients including a higher grade of Luminal B subtype which indicate
that young women may have a different tumor biology. But after adjusting for these
factors, stage of disease and treatment there was not difference in recurrence free
survival between younger and older.
Limitations for this study was the small amount of samples available and also
the short amount of time of 55 months. The study does not represent the general
population as a whole. There might be a variation in patient overtime, specially in
multicenter studies. This report is minimal since everything happened at the same
oncology team where all the patients were treated in recent years. A larger sample size
with more data may bring other clinical results with the differences between young
women and older women with HR+/HER2- breast cancer. However, after adjusting for
these factors, stage of disease, and treatment, there was no difference in recurrence
free survival between younger and older patients.