What are the pointers in history to a malignant change?

• A 42-year-old male with no active medical problem noticed a thyroid nodule 1 year back and was told by ENT specialist not to worry about it. Now he has come as he feels that the nodule is becoming more prominent. 

• Physical examination: 1 × 2 cm right lower pole nodule. There is also a lymph node which is hard and about 2 cm in size in the upper cervical chain in the right lateral neck region. An ultrasound is done which shows features of multinodular goiter. The FNA is done from the lymph node which showed metastatic papillary thyroid cancer. The patient was subjected to total thyroidectomy with radical neck dissection.

What are the pointers in history to a malignant change?