I've complex hypoechoic well defined mass in thyroid. what does this mean? other symptoms heavy night sweats, mid cycle bleeding, hair loss, blemishes

Vague: As many descriptors as they used for describing that nodule, it is still fairly vague. The word complex is thrown around a lot, but it really doesn't mean much. Does it mean fluid components, calcium, or what? The main important determinants for concernig thyroid nodules that need biopsy are size, whether its solid, and whether there are micro or macro calcifications.

Thyroid Nodules: About 5% of thyroid nodules are cancers. Your doctor should carefully review the ultrasound (not just the report) and decide whether or not your nodule requires a biopsy (fna = fine needle aspiration) to check for cancer and check thyroid levels. If thyroid levels are normal, nodule would not be the cause of your symptoms.

See answer: There are many us criteria to characterize a thyroid mass including size, shape, margin, halo, calcifications, echotexture, and vascularity. Your us may show a benign colloid nodule, but your dr. Needs to see the report /discuss with the radiologist, and exam you to see if your symptoms are thyroid related, and consider thyroid function studies.