The Thyroid Incidentaloma

Dimyati AchmadDepartment of Surgery Faculty of Medicine

Padjadjaran University/ Hasan Sadikin Hospital Bandung Indonesia

• Female, 70 years old after cancer resection 6 months ago due to anal cancer, undergo positron emission tomography to determine distant metastases.

• There is no sign and symptom thyroid gland disorder on physical examination.

• PET Exam. revealed: No sign of distant metastases, but there is a focal uptake in the thyroid gland.

Introduction

Thyroid Incidentaloma (T.I.) Is a thyroid lesions detected during Imaging investigation unrelated to examination of thyroid gland

• Prevalency of T.I. increased as the extent of use Ultrasonography (USG), Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and especially Positron Emission Tomography (PET).

• Currently PET scans with 18F flourodeoxyglucose (FDG-PET) are widely used in the management of patients with malignant conditions of various organ systems, especially to determine the extent of the primary tumor, regional nodal metastases and distant metastases.

Until today the management of T.I.

is still dilemmatic

whether put on further investigation or not.

This problems has actually been there beforebut again brought attention

due to development imaging technologysuch as PET scans.

We review some articles about T.I. to conclude

the appropriate management.

There are some clinical features of T.I. suspicious malignant

Gender : MaleAge : < 20 years or > 60 yearsPrior head and neck irradiationFamily history of thyroid carcinomaLateral neck lymphadenophaty

USG Examination

Prevalence of T.I. : 9,4 % - 27 %

Characteristics of suspicious malignant : 1. Microcalcification 2. Irreguler margin 3. Incomplete halo.

CT / MRI Examination

Prevalence of T.I. :CT : + 11.3%MRI : + 13%

CT or MRI examination can not be revealed the malignant form because there is no characteristic to differentiated them.

PET Examination

Prevalence of T.I. : 1.1% - 8.4%

No PET Studies

No. Thyroid Incidentaloma

No. Biopsi Prevalency of

Malignancy

49.714 1.286 ( 2,6 % ) 481 ( 37,5 % ) 156 ( 32,4 % )

Mostly of cases are benign lesions.32.4% malignant cases : the most histopatology result is micropapillary thyroid carcinoma which is a slow growing, good prognosis and the 10-year diseases specific mortality < 1%

Focal Multifocal Diffuse

Focal uptake description indicated is neoplastic process.

FDG uptake in the thyroid gland, PET interpretation which was greater than background activity in adjacent tissues and blood pool, was classifed as :

PET Interpretation

Standart Uptake Value (SUV) The relationship between malignant with SUV

is still debatable.

Size of nodule No significant different between nodule > 1

cm in diameter compared with 1 cm or less nodule in diameter to determine malignancy.

Management of T.I.

The Principles of T.I. Management

1. We should be considered the balancing between benefit of early diagnosis and treatment with cost-effectiveness.

2. The prognosis of the primary tumor should be take into account before investigating a potential thyroid lesion.

There is no benefit to investigate T.I. in

patient with widespread distant metastasis

and poor overall survival from the primary

tumor.

we summarized the management of T.I. inan algorithm, hopefully can explain the related dilematic issues. We emphasized in yellow highlight form.

Management Algorithm for T.I.PET. Exam

Focal Multifocal / Diffuse

Clinical Feature

Suspicious Malignancy

Non Suspicious Malignancy

USG Exam

Suspicious Malignancy

Non Suspicious Malignancy

USG-Guided FNA

Malignant or Suspicious Benign

Surgery

Regular Follow - up with USG

CT/MRI

Conclusions

• Until today, the management of T.I. is still controversial.

• We should be considered the balancing between benefit of early diagnosis and treatment with cost-effectiveness

• In cases of T.I. which are male, age < 20 years or > 60 years, previous head and neck irradiation, family history of thyroid cancer and lateral neck lymphadenopathy which should be undergo further investigation.

• In case without clinical features of malignancy we can do observation with repeat ultrasound to evaluate change of size and determine sign malignancy based on USG characteristics.

Thank You