Follicular Carcinoma Thyroid

Follicular Carcinoma Thyroid

Follicular Carcinoma Thyroid

Pulsatile tumor in the scalp and a thyroid swelling is typical of Follicular carcinoma thyroid.

Follicular carcinoma is diagnosed histologically based on the capsular and vascular invasion.

The capsular and vascular invasion cannot be better appreciated in a Fine Needle Aspiration Cytology (FNAC).

Hence the type of Thyroid malignancy which cannot be diagnosed with FNAC is Follicular Carcinoma Thyroid.

Haematogenous spread is more common in Follicular Carcinoma Thyroid.

Clinically skull metastasis is pulsatile in nature because of the increased vascularity.

Hurthle Cell Tumor is a variant of Follicular Neoplasm.

The cell of origin of Follicular Carcinoma Thyroid is the Follicular epithelium of the gland.

Follicular Carcinoma Thyroid is grouped under Differentiated Thyroid Cancer.

Differentiated Thyroid Cancer is the only human cancer where age of the patient is included in the tumor staging system.

Surgical Treatment of Follicular Carcinoma Thyroid is Total Thyroidectomy, Functional Neck Dissection for the nodal disease and Radio Iodine ablation with suppression of TSH.

Functional Neck Dissection means removal of all the lymphatics and lymph nodes on the affected side of neck with preservation of Sterno Cleido Mastoid Muscle, Spinal Accessory Nerve and Internal Jugular Vein.

The treatment of metastasis in Follicular Carcinoma Thyroid is Radio Iodine Therapy.

For Radio Iodine Therapy, the whole of thyroid tissue must be removed surgically. If there is some remnant thyroid is left, the metastasis will not take up the radio iodine.

Thyroid Stunning Effect

Scanning dose of I¹³¹ used for thyroid scan can cause damage of follicular cell resulting in decreased uptake in the thyroid remnant or metastasis. This can inturn impair the therapeutic efficacy of subsequent I¹³¹ therapy.This is called thyroid Stunning Effect.

Stunning effect occurs at the cellular level.

Higher the dose of I¹³¹, more the incidence of Stunning

The following methods are used to avoid stunning:-

-Use smaller dose of Iodine ¹³¹ for diagnosis

-Use of Iodine ¹²³

-Shorter interval between diagnostic and therapeutic doses, that is less than 72 hours.

                                               Image Courtesy: Madurai CME 2013