My sister might have a nodule on her thyroid. Which might b cancer. What can b done to fix it. And what r some longterm effects that can happen?

Surgery. Patients with thryoid nodule cytology results suggesting cancer or suspicious for cancer should be referred for surgery. The most common postoperative complications of thyroidectomy include recurrent laryngeal nerve damage, hypoparathyroidism (from parathryoid gland damage or loss), and dysphagia (difficulty swallowing). If a thyroidectomy is done, lifelong thyroxine replacement will be necessary.
Neck Lump. How did you figure out that your sister has a thyroid nodule? A lump on neck area needs to be checked by a physican. It could be a very benign lymph node, nodular goiter or a malignant tumor. In any case your sister should be seen by a physician who can guide better after history and physical examination.
Depends. Treatment depends on the nodule. In some cases it is followed with ultrasound every few months to monitor its growth. In other cases a needle biopsy is recommended and in others surgery may be indicated to remove the nodule entirely with part of the thyroid.