Ch. 4 Abnormal Screening Mammogram

Question 1

What is the most likely dx?

Answer 1

Malignancy (fine, linear calcifications on mammogram)

This is likely from dead cancer cells lining the ducts that outgrow their blood supply

Since the lesion is small and there is no palpable mass, it most likely represents DCIS as opposed to invasive ductal carcinoma.

In addition, she has a family hx of breast cancer which inc. her risk.

Question 2

Why is mammography not useful in young women (<30 y/o)?

Answer 2

Younger women tend to have denser breast tissue due to decreased level of fat. Dense breasts make it difficult to detect abnormal calcifications or masses.

Question 3

What is the Gail Risk Model?

Answer 3

Most commonly implemented risk assessment model aka Breast Cancer Risk Assessment Tool (BCRAT)

Mathematical model used to calculate risk of developing breast cancer –> considers factors such as age, age at menarche, reproductive hx, family hx in 1st degree relatives, prior biopsies

One disadvantage of the model is that it can underestimate breast cancer risk in women with a strong family hx of breast or ovarian cancer that does NOT involve 1st-degree relatives

Question 4

Pathophysiology

What is one quick feature to help differentiate between benign and malignant conditions on mammography?

Answer 4

Larger calcifications (macrocalcifications) are almost always benign, while smaller calcifications = more frequently seen in patients with breast cancer

Question 5

What is the next step if stereotactic biopsy demonstrates LCIS?

Answer 5

Excisional biopsy to r/o presence of adjacent cancers that are sometimes found

**unlike DCIS, LCIS = risk factor for developing invasive cancer in EITHER breast**

This differs from lumpectomy in that only a conservative amt of tissue is removed to get a better sample of the area (unlike the larger portion removed during lumpectomy)

Goal: not to obtain “clear margins” (as you would in DCIS), but to make sure there is not a nearby cancer

If final path shows only LCIS, then no further surgery is recommended (even if LCIS is found at margins) –> this is b/c LCIS = marker for an increased risk of breast cancer (lobular or ducal) in either breast

Treatment planning involves carefully monitoring pt for development of invasive cancer with serial mammograms + PE

Question 6

What is the next step if stereotactic biopsy shows invasive ductal carcinoma?

Answer 6

Lumpectomy (to negative margins) + SLNB –> radiation therapy to the remainder of the breast

OR

Mastectomy + SLNB (w/o radiation)

Question 7

Can you get lymph node metastasis with DCIS?

Answer 7

DCIS, is by definition, confined within the mammary duct and has not breached the BM allowing it to enter surrounding tissue or lymph system. However, when DCIS is multifocal, comedo subtype, or high grade, it may have an invasive component that is missed and subsequently result in lymph node metastasis. This occurs in a small number of DCIS cases. As such, SLNB is generally not recommended for DCIS. However, for certain high-risk lesions such as extensive microcalcifications on mammogram or DCIS associated w/ a palpable mass, SLNB is considered.