Left thyroid nodule (2.5). fna cytology shows cellular follicular lesion suggestive of neoplasm, oncocytic type. then further afirma testing shows bethesda iv and benign. dr says not cancer. is the afirma accurate? should i be worried?

Yes, your nodule is likely not cancerous, i.e. benign. Pathology is read as follicular neoplasm (Bethesda IV) which has the risk of malignancy of 25-40% so thyroidectomy is usually recommended in the past but this practice has changed with molecular testing (Afirma) which only miss 3% of malignant cases if test is (-). You will have a follow-up ultrasound in 1-2 years for making sure no change.

Your Thyroid has a Nodule which on biopsy is bordering on being Cancerous. Under your circumstances, I would advise you to get it removed surgically. The final diagnosis will remain ambiguous until your have had a good pathology examination from the fully removed Nodule. It will likely require a partial thyroidectomy.