Breast Flashcards
Define Breast Cancer and its common classifications
Breast cancer is derived from the epithelial cells (carcinoma) lining the terminal duct lobular units. It is classified as in-situ or non-invasive if the cancer cells remain within the basement membrane. If not, it is classed as invasive breast cancer.
What is the epidemiology of Breast Cancer?
Breast cancer is the most common cancer in women worldwide.
What are the risk factors for Breast Cancer?
Risk factors for breast cancer include:
- Sex - 100x higher in women than in men
- Age - The incidence of breast cancer doubles every 10 years until menopause, after which the increase slows down.
- Geographical variance/race - Breast cancer rates around the world are similar, until after the age of 50. Generally, incidence is greatest in Caucasians. [Interesting study where they compared incidence in Japanese women in Japan, Hawaii and America; they found that incidence was greatest in American Japanese women, followed by Hawaiian, and lowest in Hawaiian Japanese women].
- High socioeconomic class - may be due to increased diagnosis, or exogenous hormone use.
- Positive family history/genetic predisposition. Although only 5% of breast cancers are due to strong genetic predisposition, genetic predisposition may play an important part in the development of the other 95% of breast cancers. The risk ratio for breast cancer rises with increasing numbers of affected relatives. The risk ratios are 1.8, 2.93, and 3.9 for women with 1, 2, and ≥3 affected first-degree relatives, respectively.
- Early age at menarche and late age of menopause - increased endogenous oestrogen exposure.
- Late age of parity - women who have their first child before the age of 18 have a breast cancer risk that is one third of the risk of patients who first become pregnant after the age of 35 years.
- Exogenous oestrogen/progestogen exposure - oral contraceptive pill or HRT
Other strong risk factors include: high levels of alcohol consumption, radiation exposure, previous benign breast disease, and increased breast density.
What are the clinical features of Breast Cancer?
Screen-detected cancer is usually asymptomatic, as otherwise it wouldn’t have been screen detected.
Symptomatic cancer usually presents with a painless increasing mass (see Breast Lump Assessment). A lump that is ill-defined and immobile points towards cancer.
There may also be nipple symptoms such as discharge (only 5-10% of patients with bloodstained discharge have malignancy). Spontaneous discharge can be a sign (but also normal is lots of patients), all patients with that should be examined. Nipple retraction (a slit-like nipple) is a sign of benign disease, but nipple inversion is a sign of breast cancer and breast inflammation.
Other skin changes such as skin dimpling, an eczema-like rash on breast or skin ulceration are other signs of breast cancer.
Breast pain is only rarely a symptom of cancer, but is a sign of other breast diseases.
How is Breast Cancer investigated?
Triple assessment is the combination of:
- Physical examination
- Imaging (if ≥35 years old then mammography with or without ultrasound, if <35 then ultrasound only).
- Core biopsy, FNAC or both.
Mammography is X-raying the breast tissue. Two views - oblique and cranio-caudal are obtained. Breasts are relatively radiodense, so should not be performed in women under 35 years of age, unless cancer is clinically suspected. Mammography can show lesions of mass, areas of parenchymal distortion, and microcalcifications.
Ultrasonography is quite useful. Breast Cysts show up as transparent objects. Other benign lesions tend to have well-demarcated edges, whereas cancerous lesions have indistinct outlines.
MRI is an accurate method of imaging the breast tissue. It is very sensitive to breast cancers, but not very specific. It is therefore mainly used to assess the extent of invasive lobular cancers, and also the response of neoadjuvant therapies.
After biopsy, cytology is usually used to test for hormone receptors such as oestrogen receptor (ER), and progestogen receptor (PR). HER2 receptor testing is also important. Identifying these guide management and prognosis.
[What is the management of breast cancer?]
For a ER+ tumour:
• Tamoxifen (Selective Estrogen Receptor Modulator) given to pre-menopausal women.
• Letrozole/anastrazole/exemestane (aromatase inhibitor) given to post-menopausal women.
Also give osteoporosis prophylaxis (calcium carbonate / ergocalciferol) and bisphosphonates.
For HER2+ tumours use doxorubicin + cyclophosphomide (called AC treatment). Also other choices.
For HER2- tumours surgery is the first-line treatment. This will include chemotherapy and radiotherapy if there is nodal involvement.
What is the definition and epidemiology of Breast Cyst?
A breast cyst is a fluid filled sac within the breast, derived from a terminal duct lobular unit. It may be part of fibrocystic breast disease. Breast cysts are quite common, and prompt women to seek medical attention.
What are the clinical features of Breast Cysts?
Breast cysts are influenced by hormonal function and fluctuation. They therefore occur during lobular development, menstrual cyclic changes, and lobular involution in premenopausal and menopausal women.
A breast cyst can present as a painful or painless, often solitary mass. The mass may be large, small, or a cluster of microcysts.
Acute enlargement of the cyst often causes severe, localised pain, sudden in onset.
On Examination:
Physical examination cannot definitively distinguish between benign cyst, benign solid mass, and a malignancy.
A large or small cyst can be palpated as a smooth, firm, discrete, and frequently tender mass.
How is a Breast Cyst investigated?
An ultrasound is used to differentiate a mass that is fluid filled, solid, or mixed. The cyst is classified as simple, complicated, or complex based on ultrasound findings.
A mammogram can show large cysts or a cluster of small cysts. Small microcysts are typically not visualised on a mammogram.
What is the definition and epidemiology of Fibroadenomas?
A fibroadenoma is a benign solid tumour containing glandular as well as fibrous tissue. In 20% of cases, there can be multiple fibroadenomas. Fibroadenomas are common, and account for 13% of all symptomatic lumps.
What is the aetiology/risk factors of Fibroadenomas?
Unknown aetiology, but has a relationship with hormone levels; they can increase in size during pregnancy or oestrogen therapy, and regress after menopause.
The risk of subsequent breast cancer developing is only increased if the fibroadenoma is complex, if there is adjacent proliferative disease, or if there is family history of breast cancer.
What are the clinical features of Fibroadenomas?
Presentation is a well-defined, firm, highly mobile and non-tender mass on physical examination.
Can also present with pain.
