42. Mucinous carcinoma

This slide is no longer part of the curriculum as of spring 2020, so you shouldn’t have to learn it.

Overview

Staining: HE

Organ: Breast

Description:

The top of the slide shows normal breast tissue. The tumor is obvious.

The tumor cells form clusters that are “floating in a sea of mucin”. These tumor cells have lost their orientation and therefore secrete mucin outwards instead of inwards (into an acinus)

Diagnosis: Mucinous carcinoma

Risk factors:

  • Usually older women
  • Probably same as for other breast cancers
    The arrows show the direction in which the tumor cells are secreting mucin

Theory:

Mucinous carcinoma is a rare type of breast carcinoma, accounting for less than 3% of cases. It has a better prognosis than invasive ductal carcinoma.