Mucinous Carcinoma of the Breast: Clinicopathological Analysis with Emphasis on Biomarker Expression and Incidence of Metastasis and Recurrence
Natalie Webster, Ossama W Tawfik, Fang Fan. University of Kansas Medical Center, Kansas City, KS
Background: Mucinous carcinomas are typically ER and PR positive and do not usually overexpress the HER2 protein. They are generally associated with low rates of local and systemic recurrence. The goal of this study is to assess the clinicopathologic features and biomarker expressions of breast mucinous carcinoma cases and their association with axillary lymph node metastasis and systemic recurrence.
Design: Cases of pure mucinous carcinoma (>90% mucinous) and mixed mucinous carcinoma (<90% mucinous) of the breast were identified from our surgical pathology files between 1997 and 2012. Histopathologic data, including histologic grade, nuclear grade, and lymph node metastases was collected. The tumor biomarkers expression including ER, PR, and HER2 status was also collected in addition to clinical information such as age, tumor size, and incidence of local recurrence and distant metastasis.
Results: 36 cases of mucinous carcinoma and 13 cases of mixed mucinous carcinoma were identified. The clinicopathologic data and biomarker profile of these cases are shown in the following table.
|Pure Mucinous Carcinoma (n=36)||Mixed Mucinous Carcinoma (n=13)|
|Mean Age (years)||67 (range 42-88)||56 (range 41-74)|
|Mean Tumor Size (cm)||1.5 (range 0.1-6.8)||3.0 (range 0.8-10.5)|
|Nuclear Grade||1: 19||1: 0|
|2: 17||2: 10|
|3: 0||3: 3|
|Histologic Grade||1: 28||1: 0|
|2: 8||2: 10|
|3: 0||3: 3|
|Axillary Lymph Node*||Positive: 3||Positive: 7|
|Negative: 27||Negative: 5|
|Follow-up (months)||41 (range 0-99)||46 (range 9-116)|
|Recurrence*||Yes: 2||Yes: 3|
|No: 27||No: 3|
|Death*||Yes: 0||Yes: 0|
|No: 29||No: 13|
|ER/PR/HER2 Status||ER+/PR+/HER2-: 34||ER+/ PR±/HER2-: 10|
|ER +/PR -/HER2-: 2||ER+/ PR±/HER2+: 3|