Papillary Tumours

Papillary breast cancer is a very rare type of invasive ductal breast cancer that accounts for fewer than 1% of all breast cancers. 
The name comes from finger-like projections, or papules, which are seen when the cells are looked at under the microscope.

Many papillary tumors are benign.  These are called papillomas. 
Even when a biopsy is negative for cancer, the pathologist often needs to look at the whole tumor under the microscope to be sure about the diagnosis. This is why surgery to remove a papilloma is usually recommended, even if it is thought to be benign.

Malignant papillary tumors are a form of breast cancer.  Like other types of invasive ductal cancer, papillary breast cancer begins in the milk duct of the breast. Most of the time, papillary breast cancers include both in situ cells (which have not yet spread outside of the duct) and invasive cells (which have begun to spread outside of the duct).

Papillary breast cancers are usually small, and positive for the estrogen and/or progesterone receptors (ER/PR+) and negative for the HER2 receptor (HER2-). 
Compared to more common types of breast cancers, papillary breast cancers are less likely to involve the lymph nodes, are more responsive to treatment, and may have a better prognosis than more common types of invasive ductal cancer.

Local therapy is aimed at preventing the cancer from coming back in the breast. Local therapy includes surgery (lumpectomy or mastectomy), and may include radiation.

Systemic therapy is used to prevent the disease from coming back or spreading to another part of the body.  This may include endocrine (hormone) therapy, chemotherapy, and therapy that targets the HER2 protein.  Often different types of treatment are used together to achieve the best result.

The treatment plan will be based on the features of the tumor (type of cells, tumor grade, hormone receptor status, and HER2 status) and the stage of the disease (tumor size and node status).