Date of Award
Medical Doctor (MD)
Meena S. Moran
Purpose/Objectives: This study was conducted to assess whether a relationship exists between breast cancer molecular subtype and extent of regional lymph node involvement at disease presentation in a cohort of early-stage breast cancer patients treated with breast conservation therapy (BCT). Furthermore, clinical-pathologic features and disease outcomes were correlated with tumor molecular subtype. Materials/Methods: Eligible cases were stage I/II disease who had undergone BCT and had available slides for a central pathological review and tissue microarray analysis (TMA). After staining and categorization of each case by ER, PR, and HER-2 status, the constituents of the cohort were classified as luminal A and B, HER-2 or triple negative (TN). Data regarding extent of nodal disease was abstracted from pathology reports, and correlated to the four tumor molecular subtypes. Additional clinical-pathologic features were also analyzed to assess if any association between tumor molecular subtype and other patient/tumor characteristics exist. Outcomes were evaluated via Kaplan-Meier Survival Analysis (KMSA). Results: The median follow-up time for this cohort of 453 patients was 7 years. Assessment of N stage as a function of molecular subtype did not reveal any statistically significant difference (p = 0.54). There was no statistically significant difference in the percentage of patients who presented with nodal positive disease (p = 0.70) or in the number of positive nodes at the time of presentation (p = 0.66) across the four subtypes. However, there was a statistically significant difference in the pathologic T stage at the time of presentation in which on subgroup analysis, the TN subtype was more likely to present with T Stage II/III disease as compared to the remaining subtypes (44.4% vs. 23.5%) (p < 0.01). There were statistically significant differences in the KMSA for distant metastasis-free survival time (p < 0.01) and disease-free survival observed in this cohort (p = 0.02). Conclusions: Although a significant association between tumor molecular subtype and extent of regional lymph node involvement was not demonstrated, a significant association between tumor molecular subtype and primary tumor size was identified. These hypothesis-generating findings will need to be confirmed through future investigations.
Jones, Tiffanie, "Association Between Tumor Molecular Subtype And Extent Of Regional Lymph Node Disease In Breast Conservation Therapy" (2012). Yale Medicine Thesis Digital Library. 1729.