Thyroid Malignancies MCQs

Are tumours of the parafollicular (C cells) derived from the neural crest. rather than the cells of the thyroid follicle as are other primary thyroid carcinomas. The cells are not unlike those of a carcinoid tumour and on histological analysis a characteristic amyloid stroma is seen. High levels of serum calcitonin and carcinoembryonic antigen are produced by many medullary tumours, which should be tested for in suspected cases. Calcitonin levels fall after resection and rise again with recurrence, making it a valuable tumour marker in the follow-up of patients with this disease. Diarrhoea is a feature in 30% of cases and this may be due to 5-hydroxytryptamine or prostaglandins produced by the tumour cells. Reference : Bailey & Love's short practice of surgery, chapter: 55, Edition: 28th, Pg: 870-871

Explanation: Papillary thyroid cancer is the most common type of thyroid cancer overall, comprising 84% of all incident cases. Histologically, PTC is characterised by complex branching papillae with pseudo-inclusions, nuclear grooving, and psammoma bodies. The so-called follicular variant of PTC (fvPTC) has a similar prognosis to classical PTC and histologically has well-defined follicles with minimal papillary projections. Other less common but more aggressive histologic subtypes of PTC include tall cell, hobnail, diffuse sclerosing, and columnar variants, which together comprise less than 1% of all PTCs.

This is one of the most aggressive malignancies in humans. Thankfully it is rare. It may develop de novo , or present as dedifferentiation of a papillary or poorly differentiated carcinoma. The disease is characterised by rapid growth, visceral invasion and distant metastases. The surgeon’s role in this disease is crucial. Thyroid lymphoma can be incorrectly diagnosed as anaplastic cancer and so biopsy is critical. This can be done using a core or open technique. Reference : Bailey & Love's short practice of surgery, chapter: 55, Edition: 28th, Pg: 868

Total thyroidectomy remains the preferred evidence-based approach for DTCs associated with higher risk factors, such as: Tumor size of at least 4 cm. Presence of gross extrathyroidal extension. Evidence of metastatic disease. Radiation-induced DTC. Familial non medullary thyroid cancer. Multifocal bilateral DTC. In summary, the management of differentiated thyroid carcinomas has evolved to consider a more tailored approach, with total thyroidectomy reserved for higher-risk cases. Smaller tumors, between 1 and 4 cm, without specific high-risk features may be managed with thyroid lobectomy or near-total thyroidectomy based on the patient's clinical profile. Reference : Sabiston textbook of Surgery, chapter: 37, Edition: 21st, Pg: 903

In b\l recurrent laryngeal nerve injury, both the abductor's of vocal cords(posterior cricoarytenoid-safety muscle of larynx) is paralysed So the vocal cords come into cadaveric position which is very dangerous leading to stridor If u\l recurrent laryngeal nerve injury, there will be only hoarseness of voice If external laryngeal nerve injury, there will be husky voice If internal laryngeal nerve injury -leads to aspiration, as sensory innervation of larynx is lost