Patterns of metastasis in follicular thyroid carcinoma and the difference between early and delayed presentation

Abstract

INTRODUCTION Follicular thyroid cancer (FTC) has a good prognosis if treated early. The aim of this study was to look at the difference in outcomes in those who presented with metastasis early or late in their disease. METHODS A retrospective cohort study was conducted of patients diagnosed with FTC (n=91) treated between 2000 and 2013. Demographic, laboratory, pathological and survival data were collected and analysed. RESULTS Metastatic FTC was diagnosed in 20 cases (22%). The median age at diagnosis was 65 years (range: 17-86 years) and 65% of the patients were female. Twelve patients (60%) were diagnosed with metastatic disease at presentation, with the bones being the most common site (75%). In the remaining eight cases (40%), metastasis developed at a median of 4.5 years (range: 2-8 years) after initial thyroid surgery, lungs being the most common site (50%).Eighteen patients (90%) underwent surgical intervention for the primary disease. Sixteen patients (80%) received adjuvant radioactive iodine and eight (40%) received external beam radiotherapy. Widely invasive follicular cancer was the predominant histological diagnosis (90%). No prognostic association was observed with any of the parameters studied. The overall disease specific mortality rate was 40%. There was no significant difference in mortality between those who presented with metastatic disease and those who developed metastasis during the follow-up period (33% vs 50%, p=0.61). CONCLUSIONS The clinical outcome and prognosis for cases with metastatic disease is generally poor. Despite this, almost half of the patients in our study were still alive at a median follow-up of 5.5 years, regardless of whether they were diagnosed with metastatic disease on initial presentation or whether they developed metastasis after initial thyroid surgery.

Bilateral Choroidal Metastases as Initial Presentation of Widespread Follicular Thyroid Cancer

“…About 15% of patients with follicular thyroid cancer have metastases beyond the cervical or mediastinal margins on initial presentation or it may occur as a delayed presentation following initial treatment. 7 In patients whom a metastatic disease was diagnosed at initial presentation, the predominant metastatic sites were the lungs (49%), bones (25%) both lungs and bones (15%), and lastly CNS and other soft tissues (10%).…”

“…The peak incidence is in the 4th and 5th decade with a female predominance. 7 Many cases are subclinical. Follicular thyroid cancers come to medical attention after finding a thyroid nodule on physical examination or incidentally by radiographic workup.…”

Adrenal metastasis as the initial diagnosis of synchronous papillary and follicular thyroid cancer

“…Male sex, older age, tumor size, and FTC diagnosis were relevant risk factors in our patient. In FTC specifically, the most common sites of distant metastases are bone (42%), lung (33%), and brain (17%) [ 7 ], which have been attributed primarily to hematogenous spread [ 8 ]. Adrenal metastases are rare, accounting for approximately 1.7% of DTC distant metastases [ 9 ], with only seven cases of FTC with metastases to the adrenal gland reported in the literature [ 9 – 15 ].…”

Characteristic of risk factor of thyroid cancer related metastatic bone disease at Sanglah General Hospital Denpasar between January 2013 to March 2019

“…15 Some studies suggest that poor outcome in bone metastasis may be due to lack of effectiveness of radioactive iodine therapy. 16,17…”