Which of the following risk factors has the strongest association with this patient’s tumor?

A 50-year-old woman has been aware of a mass in her left breast for the past 6 months. A 4-cm mass is palpated on examination. The mass is hard, tender, and fixed to the overlying skin. A lumpectomy is performed. The surgical specimen is firm, has poorly defined margins, and cuts with a gritty sensation. The cut surface is gray, opaque, and slightly depressed. Streaks of gray connective tissue extend into the surrounding fibroadipose tissue. The tumor histology is shown in the image. Which of the following risk factors has the strongest association with this patient’s tumor?

image

  1. Exposure to carcinogens
  2. Family history
  3. Fibrocystic change
  4. Obesity
  5. Smoking