Though the presence of any lump in either one or both the breasts is associated with the development of breast cancer, in most cases, this lump might only be benign. However, there are a few early signs and diagnosis of breast cancer, which you should know about. 

The symptoms of breast cancer
Before getting to the diagnosis, let’s address the common symptoms in the early stages.

• Visible changes in the nipple shape
• Pain in the breasts, which wouldn’t go away even after the next period
• Development of a lump, which wouldn’t go away even after the next period
• Clear, brown, red, or yellow nipple discharge from the breasts
• Itchiness, unexplained redness, rash, skin irritation, or swelling on breasts
• A lump or swelling around underarm or near the collarbone.

If the lump has irregular edges or is hard, it might be cancerous. 

When breast cancer progresses, the symptoms tend to aggravate. In this stage, the common symptoms include:

• Vaginal pain
• Visible dimples on the surface of the breast
• Enlargement of either one of the breasts
• Inverted nipples
• The existing lump grows bigger
• Incomprehensible weight loss
• The appearance of veins around the breasts
• Lymph nodes of the armpits grow larger.

It is important to know that occurrence of these symptoms does not always translate to the development of breast cancer. So, early signs and diagnosis of breast cancer go hand in hand. As soon as any signs appear, one should head to the doctor for a diagnosis.

Diagnosis
For the diagnosis of breast cancer, the doctor might undertake some breast examinations. These include: 

Physical examination: The doctor will first perform a physical examination of the breasts to analyze the breasts and the skin around the breast. This will be followed by checking the nipples for any discharge or problems. Following this, the nearby area would be examined to check for any visible lumps. 

Past medical history: Following a physical examination, the doctor will question a person about past health history. It would include questions like, if anyone in the immediate family has or had breast cancer or if they have been currently taking any specific medications. At times, breast cancer is associated with the genes. Thus, a person needs to share family history and medical history with the doctor. Next, the doctor will ask questions about the symptoms that one has been experiencing.

Mammogram: A mammogram might also be performed, which is primarily the X-ray for the breast. With the help of it, the doctor will be able to understand whether the lump is a malignant or a benign mass. 

Ultrasound: To get the image of the surrounding breast tissues, an ultrasound might be performed. 

MRI: This, too, helps in getting the images for the examination of the breast tissues.

Biopsy: A biopsy involves the removal of a part of the tissue from the breast for testing.