Medullary carcinoma is a very rare diagnosis in breast cancer and accounts for only 3 to 5% of breast cancer cases. It owes its name to its colour, which looks like the brain’s medulla tissue colour. This cancer starts with milk ducts of the breast and invades other surrounding tissue. The incidence rates are high in women aged between 45 to 55. This subtype if IDC is slow growing cancer though appearance wise these tumor cells look very aggressive and have a clear distinctive boundary with the healthy surrounding tissue. These cancerous cells look large and very abnormal compared to healthy tissue. The incidence of this cancer is known to be higher in women with BRCA1 mutation. It is relatively easier to heal this type of cancer as it is low tendency to invade the lymph nodes outside of the breast. The tumor growths are usually restricted to less than 2 cm in size.
This carcinoma at the outset similar to other cancers does not have any visible symptoms. Over time with the tumour cells building up which are large in size and concentrated at the site of origin, you may feel a soft lump in the breast. This may feel a bit spongy like a breast cyst. The swelling is caused from inside of the breast and as such with progression there may be symptoms like swelling, pain, reddening of the breast skin.
The step by step diagnosis process involves a basic initial physical examination of the breasts for detecting any lumps or firm tissue in the breast. This is followed by imaging tests. First a mammogram is done to visibly detect the accumulation of cancerous cells. And also to detect tuomor growths in the surrounding tissue. Ultra sound imaging is also done for the same purpose with better and clear distinctive results. This is a difficult cancer to detect and diagnose and in a mammogram test it may be confused with IDC. Thus it is important that a biopsy of the tissue is done to obtain specific information of the tumor cells. In this a tissue sample is removed from the breast for pathological tests. An open surgical biopsy or a stereotactic biopsy should be undertaken for best conclusive results in medullary carcinoma diagnosis. In this biopsy a pathologist for a true medullary carcinoma should detect the following features, in absence of which the cancer becomes a atypical medullary carcinoma. The first feature is a distinct, visible diversification boundary between the tumor cells and healthy cells. Secondly, these cancerous cells are large and quite abnormal looking as compared to healthy cells. Also they seem continuous like sheet and their intra- individual cell distinction is difficult. Lastly there is presence of white blood cells or the immunity system cells around the cancer cells.
Another specific feature true to this type of cancer is p53 protein, a positive testing for this test confirms a diagnosis of true medullary carcinoma.
Also other identifiying fetures of this carcinoma include testing of cancerous cells for hormone receptor negativity and HER2-negativity. This medullary carcinoma is distinguished by its negative affinity for hormone receptors and for protein HER2/neu.There are some other key features of medullary carcinoma:
Pathological findings and feature specific testing are the backbone of diagnosing and detecting medullary carcinoma.