breast cancer surgery and treatment

Question 1

What is the anatomy of the breast?

Answer 1

The breast consists of ducts, lobules, the nipple, fat, pectorals major, and the chest wall.

Question 2

How common is breast cancer?

Answer 2

Breast Cancer is the most commonest female cancer in the UK. 95% of cases are sporadic and risk increases massively with age.

Question 3

Where is incidence highest?

Answer 3

Incidence occurs mainly in Western countries, e.g. UK and US.

Question 4

What are the predisposing factors for breast cancer?

Answer 4

The risk factors for breast cancer can be split into 2 categories: non-modifiable and modifiable. 
Non-modifiable factors are:
1. Female
2. Age
3. Personal History
4. Dense breast tissue
5. Early menarche
6. Late menopause

Modifiable factors are:

1. Nulliparity
2. Hormone Contraceptives
3. Hormone replacement therapy
4. Alcohol
5. Smoking
6. Obesity

Question 5

What does breast cancer look/feel like?

Answer 5

1. A thick mass
2. Indentation
3. Growing vein
4. A bump
5. Nipple inversion
6. Redness/heat
7. Invisible lump
8. Dimpling
9. Fluid - this occurs if the tumour invades the duct.

Question 6

How is breast cancer usually detected?

Answer 6

Usually breast cancer presents symptomatically (e.g. lump, breast abnormality). This occurs in 60% of cases. However, 40% of cases are detected via screening.

Question 7

How is breast cancer assessed?

Answer 7

Patients with suspected breast cancer undergo a triple assessment consisting of: clinical examination, imaging, and pathology.

Question 8

How is the clinical examination assessed?

Answer 8

This usually occurs with a GP who will assess whether a lump is present, and if it presents as a malignant tumour. A malignant tumour would appear hard, painless, irregular, with potential skin dimpling. The tumour is usually fixated to skin with potential bloody discharge.

Question 9

How is the imaging assessed?

Answer 9

Imaging can occur via ultrasound or mammography (only in over 35 year olds). Mammography is 2-view and can look for micro-calcifications (fine white spots) as well as a tumour mass (appears white). In younger women, ultrasound is preferred as young breast tissue is too dense for mammography.
MRIs may also be used for superior detection but can pick up pre-invasive cancer which may never become tumours. However, MRI can be done if there is any disconcordance between other imaging.

Question 10

How is pathology assessed?

Answer 10

Pathology is done via FNAC, core biopsy, or open biopsy. FNAC looks at single cells, a core biopsy looks at more tissue.
FNAC results are graded as A1 (not a sufficient sample) to A5 (definitely malignant).
Ultrasound guided core biopsy results can be graded as B1 (insufficient sample), B2 (benign), B3 (intermediate), B4, B5 (definite cancer). B5 is split into 3 categories: B5a - DCIS, B5b - invasive cancer, B5c - maybe DCIS, maybe invasive (unclear).

Histology is important to assess the layers of cells and determine the invasive nature. As well as determining whether there were clear excision margins.

Question 11

What are the non-invasive types of breast cancer?

Answer 11

Ductal Carcinoma in situ, and Lobular Carcinoma in situ.

Question 12

What are the invasive types of breast cancer?

Answer 12

Invasive Ductal Carcinoma of No Special Type or Invasive Lobular Carcinoma.

Question 13

What is Ductal Carcinoma in situ?

Answer 13

This is a pre-invasive cancer commonly found on screening. High grade will likely become IDC, however low grade may never become IDC if left. There is a LORIS trial currently underway which is assessing this. They’re looking at whether monitoring the cancer or standard treatment is best.

Question 14

What is Lobular Carcinoma in situ?

Answer 14

This is cancer which exists in the lobules. It is not pre-invasive, but instead is a high risk marker for getting invasive cancer.

Question 15

What is Invasive Ductal Carcinoma?

Answer 15

Most of these cancer types are of ‘No Special Type’. Grade 1 tumours have typically high survival rates with 85% 10-year survival, whereas Grade 3 tumours typically have a 45% 10-year survival rate.

Question 16

What is the NPI classification used for assessing cancer stage/grade?

Answer 16

Nottingham Prognostic Index (NPI) classifies cancer based on grade, size and lymph node involvement to give a score determining whether a patient has a high risk of recurrence (this is classed as a score of 5.4 or higher).

Question 17

What is the TNM classification used for determining stage of a cancer?

Answer 17

This incorporates tumour size, lymph node involvement and metastases.
Stage 1 is considered a tumour size < 2cm, no lymph node involvement and no metastases.
Stage 2 is considered a tumour <5cm, positive lymph node involvement and no metastases, or a larger tumour (>5cm), with no lymph node involvement or metastases.
Stage 3 is fixed nodes, and tumour fixed to skin.
Stage 4 is when distant metastases occur.

Question 18

How are stage 1 and 2 tumours treated?

Answer 18

These are usually treated with surgery to remove the tumour with clear excision margins. Therapy may be given afterwards (e.g. chemotherapy) if patient has a high risk of recurrence (NPI score).

Question 19

How are stage 3 and 4 tumours treated?

Answer 19

A bone scan must be carried out to assess any distant metastases at this stage. Surgery may not be applicable straight away as the tumour may be too big to remove. In this case, neoadjuvant therapy would be started to downstage the tumour, before removal.

Question 20

What is breast conserving surgery and why is it preferred to mastectomy?

Answer 20

Breast conserving surgery involves wide local excision and removal of the tumour, whilst conserving as much of the breast as possible. This is preferred to mastectomy as it carries less psychological morbidity, a higher self image, and has similar survival rates to mastectomy. However, this is not always applicable, e.g. a large tumour in a small breast. Often WLE is accompanied by radiotherapy to reduce the risk of local occurrence, however the exposure to heart and lungs must be reduced at all costs.

Question 21

What is a mastectomy? Why might it still be used today?

Answer 21

A simple mastectomy is a procedure which involves removing all the breast tissue. This is often done in patients with family history of BRCA1/2 mutations, as this would decrease their risk of getting cancer.

Question 22

Why do oncologists stage the axilla?

Answer 22

Staging the axilla helps to define whether patients are at a high risk of recurrence and identify patients which may need adjuvant therapy to increase their survival. We can do this via sentinel lymph node biopsy, where a dye is injected to identify any metastases.

Question 23

Is it better to remove lymph nodes or undergo sentinel lymph node biopsy?

Answer 23

Removal of lymph nodes can lead to lymphedema and shoulder stiffness. The ALMANAC trial is currently looking at whether SLNB is better than standard axillary management. However, another trial (POSNOC trial) is considering whether axillary radiotherapy is superior.

Question 24

We have mentioned that WLE with radiotherapy is given for high risk patients, but what happens for intermediate risk patients after a mastectomy?

Answer 24

These patients can be entered into the SUPREMO trial which is looking at the selective use of post-mastectomy radiotherapy.

Question 25

Discuss whether Tamoxifen or Anastrazole are more beneficial. Why might other people disagree?

Answer 25

When given for 5 years, Tamoxifen has demonstrated a 20% reduction in mortality. A later meta-analysis has showed that tamoxifen has shown a 31% reduction in mortality in comparison to placebo. Trials have demonstrated that there is no difference when using Tamoxifen alone, compared to Tamoxifen + Anastrazole. Therefore we need to know which endocrine treatment to give. Anastrazole has increased disease free survival and improved recurrence compared to Tamoxifen, however many studies have demonstrated that 10-year Tamoxifen is much more beneficial with regards to overall survival, disease-free survival and recurrence rates, compared to 5-year Tamoxifen. However, extended use of Tamoxifen puts patients at risk of endometrial cancer and pulmonary embolism. It therefore can be stated that 10-year anastrazole may be more beneficial, as well as preventing endometrial cancer risk associated with Tamoxifen. However, studies have identified 5-years Tamoxifen, followed by 5-years of letrozole is an optimal combination. This would allow the efficacy of 10-year treatments, without the extended nature of a single drug, which could promote other cancer formation and pulmonary embolism.

Question 26

What is the hierarchy of chemotherapy?

Answer 26

Taxanes are better than anthracyclines. Anthracyclines are better than the CMF combination.

Question 27

How has Oncotype DX transformed therapy regimens?

Answer 27

The unique personalised tumour biology is used to give a recurrence score, e.g. low or high. These have been used to determine mainly whether combination chemotherapy will be advantageous, e.g. in high risk groups.

Question 28

How effective is Herceptin?

Answer 28

Its first clinical benefit was demonstrated in a trial which assessed patients randomised to chemotherapy, with or without Herceptin. Herceptin caused a 39% decrease in death rates when given for 1 year. However, cardiotoxic side effects have been demonstrated therefore many efforts have been made to combat this with alternatives.

Question 29

What role do genetics play in breast cancer?

Answer 29

Although very important, the genetics behind breast cancer mainly occur via somatic means, e.g. they are not inherited. Some mutations may be inherited, e.g. BRCA1/2, however there are numerous genes involved in familial case which we are not aware of yet.

Question 30

Why is immediate breast reconstruction preferred by oncologists, in comparison to delayed breast reconstruction?

Answer 30

Immediate breast reconstruction is associated with better cosmetic results, therefore reduced psychosocial complications for women. This can decrease the costs of procedures.

Question 31

How many cases of breast cancer are diagnosed each year?

Answer 31

There is a high global incidence of breast cancer with over 1,000,000 cases diagnosed per year.