Surg Today (2005) 35:480–482DOI 10.1007/s00595-004-2949-4

Case Reports

Liver Metastasis from Thyroid Carcinoma 32 Years After Resectionof the Primary Tumor: Report of a Case

Hidenori Kouso1, Toru Ikegami1, Takahiro Ezaki1, Teruyoshi Ishida1, Shiomi Aimitsu2, Megumu Fujihara3,and Masaki Mori4

Departments of 1 Surgery, 2 Internal Medicine, 3 Pathology, and 4 Radiology, Hiroshima Red Cross and Atomic Bomb Survivors Hospital,Hiroshima 730-8619, Japan

Case Report

A 73-year-old woman was referred to our hospitalfor investigation of a high-echoic solid mass in theliver, found incidentally by ultrasonography, which hadbeen done as part of screening to find the cause ofher generalized itching. The patient had undergone ahemithyroidectomy for follicular thyroid carcinomawith low-grade malignancy 32 years earlier. Computedtomography and ultrasonography showed no definitemass in the left half of the thyroid gland (Fig. 1). Labo-ratory studies showed normal liver function tests,and normal serological tumor markers including α-fetoprotein and carcinoembryonic antigen. She wasnegative for hepatitis C virus antibody, hepatitis Bsurface antigen/antibody, and hepatitis B envelopeantigen/antibody, but positive for hepatitis B coreantibody. Computed tomography showed a roundtumor, about 1.5cm in diameter, which was enhancedearly, but later washed out, in segment 5 of the liver.Hepatic angiogram showed a hypervascular tumor stainin segment 5 of the liver.

We performed laparotomy and partial resection ofthe liver after making a preoperative diagnosis of pri-mary hepatocellular carcinoma. Macroscopic examina-tion showed a 1.5-cm round tumor, which wasgray-brown and well demarcated. Microscopic exami-nation revealed follicular cells with minimal atypiagrowing in a thyroid follicular pattern with colloids (Fig.2). Thus, we diagnosed a metastatic liver tumor fromthyroid follicular carcinoma. The patient had an un-eventful postoperative course and is still well withoutany evidence of further recurrence 2 years after surgery.

Discussion

Follicular carcinoma of the thyroid gland is a commontype of differentiated thyroid cancer.1–3 Although it is

AbstractFollicular thyroid carcinoma is a differentiated canceroriginating from the follicular cells in the thyroid gland.A 73-year-old woman, who had undergone curative re-section of thyroid carcinoma 32 years earlier, was re-ferred to our hospital after ultrasonography showed asolid mass in the liver. Laboratory data revealed posi-tive hepatitis B core antibody, but all other values werenormal. Computed tomography showed a round tumor,about 1.5 cm in diameter, which was enhanced early andwashed out later, in segment 5 of the liver. She under-went laparotomy and partial resection of the liver.Microscopic examination showed follicular cells withminimal atypia growing in a thyroid follicular patternwith colloids, whereby a diagnosis of metastatic livercancer from thyroid follicular carcinoma was made.This is a rare case of solitary liver metastasis appearing32 years after eradication of primary follicular carci-noma. Although the reason for the delayed presenta-tion of the metastatic lesion remains unclear, this caseshows that patients with differentiated thyroid cancershould be followed up for their entire life.

Key words Liver metastasis · Thyroid cancer

Introduction

Follicular carcinoma is a thyroid cancer originatingfrom the follicular cells in the thyroid gland. Althoughliver metastasis from follicular carcinoma is not uncom-mon, the case we report of a solitary liver metastasisfound 32 years after curative resection of the primarytumor is extremely unusual.

Reprint requests to: T. IkegamiReceived: September 19, 2003 / Accepted: July 13, 2004

481H. Kouso et al.: Liver Metastasis from Thyroid Cancer

generally associated with good survival rates, late recur-rences leading to a prolonged disease course have beendescribed.1–3 The most common location for metastasesto arise is the lung, followed by the bone, the brain, andthen the liver.1–3 Nevertheless, finding a solitary livermetastasis 32 years after eradication of the primary fol-licular carcinoma is an exceptionally rare event.

Three previous reports have described finding laterecurrences more than 30 years after curative resectionof a primary thyroid cancer. Fonseca4 reported findinga solitary lung metastasis from thyroid papillarycarcinoma 47 years after curative thyroid lobectomy;Johnson et al.3 reported finding a solitary renal metasta-sis from thyroid follicular carcinoma 37 years after cura-

tive operation; and Cady et al.5 reported finding a recur-rence of mixed follicular and papillary carcinoma 41years after the initial diagnosis. It is possible that therewas occult, undetectable follicular carcinoma in theremnant thyroid gland of our patient, which resulted inliver metastasis. Alternatively, Kondo et al.6 suggestedthe possibility of ectopic thyroid tissue or teratomatousthyroid tissue in the liver.

Several explanations have been postulated for de-layed metastasis of differentiated tumors. Alexander7

presented an intriguing pathogenic hypothesis propos-ing that clusters of dividing cells lead to an equilibriumbetween cell death and proliferation, or that the tumorcells remain in a state of rest for long periods withoutlosing their viability before renewed tumor growth isinduced by the somatic transformation of the cancercells.

We reported a rare case of a solitary liver metastasisfound 32 years after curative resection of follicular thy-roid cancer. Therefore, patients with differentiated thy-roid cancer should be carefully followed up for the restof their life.

References

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2. Tubiana M, Schlumberger M, Rougier P, Laplanche A, BenhamouE, Gardet P, et al. Long-term result and prognostic factor in pa-tients with differentiated thyroid carcinoma. Cancer 1985;55:794–804.

3. Johnson MW, Morettin LB, Sarles HE, Zaharopoulos P. Follicularcarcinoma of the thyroid metastatic to the kidney 37 years afterresection of the primary tumor. J Urol 1982;127:114–6.

Fig. 1. Computed tomography scan showed a round tumor, 1.5cm in diameter, which was enhanced early (a), but later washedout (b)

Fig. 2. Microscopic examination revealed follicular cells withminimal atypia growing in a thyroid follicular pattern withcolloid (H&E, �100)

a b

482 H. Kouso et al.: Liver Metastasis from Thyroid Cancer

4. Fonseca P. Thyroid lung metastasis diagnosed 47 years after thy-roidectomy. Ann Thorac Surg 1999;67:856–7.

5. Cady B, Meissner WA, Sala LE. Thyroid cancer for forty-oneyears. N Engl J Med 1978;299:901.

6. Kondo T, Katoh R, Omata K, Oyama T, Yagawa A, Kamaoi A.Incidentally detected liver metastasis of well-differentiated follicu-

lar carcinoma of the thyroid, mimicking ectopic thyroid. Pathol Int2000;50:509–13.

7. Alexander P. Dormant metastases — studies in experimental ani-mals. J Pathol 1983;141:379–83.