Treatment of choice for medullary carcinoma of thyroid is -
Ans. is 'a' i.e., Total thyroidectomy Treatment of thyroid malignancies is as follows :- (Note- This is a very important and often repeated topic in PG exams, so if time permits one must turn the pages of Schwartz Sx or any other standard hook for detailed study).Papillary Thyroid Carcinoma (PCT)o High-risk tumors or bilateral tumorsTotal thyroidectomy (or near total thyroidectomy),o Low riskThe treatment is controversial.Conservative approach advocates hemithyroidectomy (lobectomy + isthmusectomy).More radical approach advocates total thyroidectomy (or near total thyroidectomy).Schwartz Sx and Devita's Oncology are in favour of radical approach.(High and Low risk decided by any one of the many classification systems)o If enlarged lymph nodes are foundModified radical neck dissection is done of the affected side.o When patients are found to have a minimal papillary thyroid carcinoma in a thyroid specimen removed for other reasons, unilateral thyroid lobectomy and isthmusectomy is usually considered to be adequate treatment, unless the tumor has evidence of angioinvasion, multifocality, or positive margins.Follicular Thyroid Carcinoma (FTC)o FNA biopsy is unable to distinguish benign follicular lesions from follicular carcinomas therefore, preoperative diagnosis of cancer is difficult unless distant metastases are present,o Patients diagnosed by FNA biopsy as follicular lesions should undergo thyroid lobectomy + isthmusectomy (because at least 80% of these patients will have benign adenomas).o The resected lobe is subjected to histology (intraoperative frozen - section examination, though usually not helpful should be performed in high risk cases).o If & follicular lesion larger than 4 cm is seen in an older patient - total thyroidectomy is done, because of high risk of cancer (50%) in this setting.o Prophylactic nodal dissection is not needed as nodal involvement is infrequent, but in the unusual patient with nodal metastases, therapeutic neck dissection is recommended.Lets also see what Sabiston 18/e p940 writes about treatment of Follicular lesions:The diagnosis of the carcinoma cannot be determined by preoperative FNA or intraoperative frozen section diagnosis of a follicular lesion.If the lesion is 2 cm or smaller and well contained within one thyroid lobe - thyroid lobectomy and isthmectomy.If the lesion is larger than 2 cm- total thyroidectomy.Medullary Thyroid Cancero Total Thyroidectomy is the treatment of choice for patients with MTC because of high incidence of multicentricity, the more aggressive course and RAI therapy usually being not effective,o The central compartment nodes are frequently involved early in the disease process, so that a bilateral central neck node dissection should be routinely performed. In patients with palpable cervical nodes or involved central neck nodes, ipsilateral or bilateral modified radical neck dissection is recommended. Similarly patient with tumors larger than 1 cm should undergo ipsilateral prophylactic modified radical neck dissection, because greater than 60% of these patients have nodal metastases. If ipsilateral nodes are positive, a contralateral node dissection should be performed.o In case of locally recurrent or metastatic disease, tumor debulking is advised, not only to ameliorate symptoms of flushing and diarrhoea, but also to decrease risk of death from recurrent central neck or mediastinal disease,o External beam radiotherapy is controversial, but is recommended for patients with unresectable residual or recurrent tumor. There is no effective chemotherapy regimeno If patients with MTC are found to have pheochromocytoma, this must be operated first.Anaplastic Carcinomao This tumor is one of the most aggressive thyroid malignancies, with few patients surviving six months beyond diagnosis.o All forms of treatment have been disappointing. If mass is resectable then thyroidectomy may lead to small improvement in survial.o Combined radiation and chemotherapy as adjuvant in resectable cases has been associated with prolonged survival. These are nowr also being used in neoadjuvant setting,o Tracheostomy may be needed to alleviate airway obstruction.
Total thyroidectomy
Partial thyroidectomy
1131 ablation
Hemithyroidectomy
Thyroid Malignancies