Differential Diagnosis for Right Breast Lump
Single Most Likely Diagnosis
- Breast Cancer (Invasive Ductal Carcinoma): The presence of a macrolobulated mass with marked increased vascularity and a BI-RADS 4 suspicious classification suggests a high likelihood of malignancy. The macrolobulated borders and adjacent nodule also raise concern for cancer.
Other Likely Diagnoses
- Fibroadenoma: Although less likely given the BI-RADS 4 classification, fibroadenomas can present as macrolobulated masses, especially in younger women. However, the marked increased vascularity and presence of a nodule make this diagnosis less likely.
- Phyllodes Tumor: These rare tumors can present as rapidly growing masses with increased vascularity. While less common than breast cancer, they should be considered in the differential diagnosis.
- Breast Cyst: Although the ultrasound description does not suggest a simple cyst, a complex cyst or a cyst with a solid component could be considered. However, the macrolobulated borders and increased vascularity make this diagnosis less likely.
Do Not Miss Diagnoses
- Inflammatory Breast Cancer: This aggressive form of breast cancer can present with a rapidly growing mass, increased vascularity, and skin changes. Although the skin surfaces are reported as normal, inflammatory breast cancer should be considered due to its aggressive nature and poor prognosis if missed.
- Metastasis to the Breast: Although rare, metastasis to the breast from other primary cancers (e.g., lymphoma, melanoma) can present as a rapidly growing mass. Given the potential for metastatic disease to be deadly if missed, it should be considered in the differential diagnosis.
Rare Diagnoses
- Pseudoangiomatous Stromal Hyperplasia (PASH): This rare benign condition can present as a rapidly growing mass with increased vascularity. However, it is much less common than breast cancer or other diagnoses listed above.
- Hamartoma: A benign breast tumor that can present as a macrolobulated mass. However, hamartomas are rare and typically have a characteristic "breast within a breast" appearance on imaging.