Abstract

Distant metastasis is uncommon in differentiated thyroid cancer (DTC) and 7% to 23% of DTC patients develop distant metastasis. The remarkably good prognosis and long-term survival in DTC are significantly reduced in patients with distant metastasis as those at the pelvic site. We report the rare case of a patient wth follicular thyroid cancer initially diagnosed as a pelvic mass. Turk Jem 2011; 15: 23-5

Özet

Introduction

Thyroid cancer is the most common endocrine malignancy and over 90% are well-differentiated papillary and follicular histological subtypes (1); follicular thyroid cancer (FTC) frequently has metastases on lungs and bones (2).  Trapezoid muscle, muscles of the extremities, choroid of the eye, adrenal glands, kidneys and pelvic region are the rare metastatic sites reported in the literature (3-8). We here report the rare case of a patient with FTC  who had  a clinical presentation of a pelvic mass.

Case Report

A 79-year-old female presented to the emergency service with abdominal pain, fever and lethargy. Mesenteric artery embolism was suspected; abdominal computed tomography  (CT) was performed. CT showed a mass measuring 7 x 7.5cm close to the sacroiliac joint and destruction of the right iliac bone (Figure 1,2). Also, sclerotic metastases in the vertebrae were reported. She was admitted to the medical oncology division. The left thyroid lobe was enlarged, with millimetric calcifications and, millimetric subpleural pulmonary nodules and pleural fluid collection were identified by chest CT. The right lobe was found to be 19x16x34mm and the left lobe was identified to be 42x53x54mm by thyroid ultrasonography (USG); hypo- and hyperechoic cystic nodules were detected, the biggest one of which was in the left lobe with 18x13x14mm dimensions. Follicular lesions in the thyroid gland and metastasis of FTC were detected by fine-needle aspiration and tru-cut biopsy from the pelvic mass (Figure 3). Laboratory analysis revealed the following: sT3:8.13 pg/mL (2.20–4.70), sT4:51.20 ng/dL (8–20), TSH:0.02 mIU/mL (0.20–3.20), thyroglobulin: 631 ng/mL (2–70), Anti-Tg Ab:32.78 IU/mL (0–60). Thyroid scintigraphy was consistent with suppressed thyroid gland. Increased dense activity involvement especially on the left side of the neck, pathologically focally increased activity involvement in the right iliac wing and focally relatively increased activity involvement in the area compatible with the second lumbar spine were detected on Technetium-99m methoxyisobutyl isonitrile (99mTc-MIBI) scintigraphy (Figure 4). The diagnosis was metastasis of follicular thyroid cancer which produces hormone and 3x2 tablets/day methimazole was started. The patient was admitted to the hospital in poor general condition, dehidrated, with urinary tract infection. She was hydrated and treated with parenteral antibiotics and, nutritional support was provided. Nasogastric feeding was started together with methimazole treatment. Despite of all treatment approaches, the patient died one month after the diagnosis because of old age and poor general status additionally complicated by respiratory deficiency.

Discussion

The prognosis of DTC is good (9) and the disease is curable. The good prognosis and estimated long survival in DTC are reduced in patients with distant metastasis (2). 7% to 23% of patients have distant metastasis (10–12). 1% to 4% of DTC are diagnosed primarily by distant metastasis (13–15). The factors that mostly affect the prognosis are old age and the site of the metastasis. Survival is better in patients who are under 45 years of age - these patients are mostly asympthomatic and will only have lung and bone metastases. At the first diagnosis, only 2% to 5% of follicular thyroid cancer patients have metastases with the exception of neck or mediastinum (9). Especially, the survival is much decreased in patients with metastases at the initial diagnosis and the reported mortality rate is between 43% and 90% (15). Distant metastases are associated with poor prognosis (16). In a study (17), it has been reported that poor prognosis criteria of metastatic DTC are distant metastases excluding the lungs, old age and diameter of metastasis ≥2 cm. More than one bone metastasis is a contributing factor to the poor prognosis. In this case, old age at the primary diagnosis, bone metastases and distant metastasis at the pelvic area with a diameter of 7.5 cm are all significant factors that affect the survival of  the patient negatively and, the patient died a short time after the diagnosis.  
Bone metastases are identified in 3–5% of patients with DTC (18) and frequently show signs of pain, pathological fractures and spinal cord compression in cases of vertebral involvement. Pain which increases in time is the essential complaint of metastatic bone disease and can be treated with opioids. Metastatic bone pain is associated with the mass effect of tumor tissue or to the stimulation of intraosseal nerve cells by the cytokines that are produced by the tumor cells (19). In our case, the patient had no complaint of pain associated with bone, or the reason of no pain complaint could be the mental changes due to thyroid function deficiency, or she was so lethargic that she was unable to complain.  It has been reported in the literature that brain, liver and skin metastases of DTC are rare (6). Metastases of follicular thyroid cancer to the right adrenal gland, the left renal (6) and pelvic regions (7,8) have been presented as case reports. This is a rare case with a soft tissue mass in the pelvic region, which is not a frequently reported metastatic area, and only 2 similar cases were formerly reported at the first diagnosis. While searching for the primary focus in a patient with a pelvic mass or with suspected metastasis, DTC (mainly follicular thyroid cancer) should be considered among other frequent malignancies.

References

1. Pagano L, Klain M, Pulcrano M, Angellotti G, Pasano F, Salvatore M, Lombardi G, Biondi B. Follow-up of differentiated thyroid carcinoma. Minerva Endocrinol 2004;29:161-74.
2. Toubert ME, Hindie E, Rampin L, Al-Nahhas A, Rubello D. Distant metastases of differentiated thyroid cancer: diagnosis, treatment and outcome. Nucl Med Rev Cent East Eur 2007;10:106-9.
3. Panoussopoulos D, Theodoropoulos G, Vlahos K, Lazaris AC, Papadimitriou K. Distant solitary skeletal muscle metastasis from papillary thyroid carcinoma. Int Surg 2007;92:226-9.
4. Pucci A, Suppo M, Lucchesi G, Celeste A, Viberti L, Pellerito R, Papotti M. Papillar thyroid carcinoma presenting as a solitary soft tissue arm metastasis in an elderly hyperthyroid patient. Case report and review of the literature. Virchows Arch 2006;448:857-61.
5. Bucerius J, Meyka S, Michael B, Biersack HJ, Eter N. Papillary thyroid carcinoma with an uncommon spread of hematogenous metastases to the choroid and the skin. J Natl Med Assoc 2008;100:104-7.
6. Garcia F, Torres M, Marco P, Pinon SF. Unusual metastasis of differentiated thyroid carcinoma. An Med Interna 2002;19:579-82.
7. Dequanter D, Abdoulaye D, Lothaire P, Gebhart M, Andry G. Isolated pelvic metastasis of thyroid cancer. Ann Endocrinol 2001;62:521-4.
8. Chaffanjon PC, Sturm N, Caravel JP, Chabre O, Brichon PY. Pelvic muscular metastasis of well differentiated thyroid cancer. Ann Chir 2004;129:1000-2.
9. Curling T, Udelsman R. Thyroid Tumors. De Vita V, Hellman S, Rosenberg SA. Cancer, Principles & Practice of Oncology 8 th. ed. Philadelphia; Chapter  2008;663-1682.
10.  Massin JP, Savoie JC, Garnier H, Guiraudon G, Leger FA, Bacourt F. Pulmonary metastases in differentiated thyroid carcinoma. Study of 58 cases with implications for the primary tumor treatment. Cancer 1984;53:982-92.
11. Samaan NA, Maheshwari YK, Nader S, Hill CS Jr, Schultz PN, Haynie TP, Hickey RC, Clark RL, Goepfert H, Ibanez ML, Litton CE. Impact of therapy for differentiated carcinoma of the thyroid: an analysis of 706 cases. J Clin Endocrinol Metab 1983;56:1131-8.
12. Brown AP, Greening WP, McCready VR, Shaw HJ, Harmer CL. Radioiodine treatment of metastatic thyroid carcinoma: the Royal Marsden Hospital experience. Br J Radiol 1984;57:323-7.
13. Leger AF. Distant metastasis of differentiated thyroid cancers. Diagnosis by 131 iodine (I 131) and treatment. Ann Endocrinol 1995;56:205-8.
14. Hoie J, Stenwig AE, Kullmann G, Lindegaard M. Distant metastases in papillary thyroid cancer. A review of 91 patients. Cancer 1988;61:1-6.
15. Shaha AR, Shah JP, Loree TR. Differentiated thyroid cancer presenting initially with distant metastases. Am J Surg 1997;174:474.
16. Shoup M, Stojadinovic A, Nissan A Ghossein RA, Freedman S, Brennan MF, Shah JP, Shaha AR. Prognostic indicators of outcomes in patients with distant metastases from differentiared thyroid carcinoma. J Am Coll Surg 2003;197:191-7.
17. Sampson E, Brierley JD, Le LW, Rotstein L, Tsang RW. Clinical management and outcome of papillary and follicular (Differentiated) thyroid cancer presenting with distant metastasis at diagnosis. Cancer 2007;110:1451-6.
18. Hindie E, Fregonora PZ, Keller I, Duron F, Devaux JY, Nocaudie MC, Sarfati E, Moretti JL, Bouchard P, Toubert ME. Bone metastases of differentiated thyroid cancer: impact of early 131I-based detection on outcome. Endocrine-Related Cancer 2007;14:799-807.=
19. Selvaggi G, Scagliotti GV. Management of bone metastases in cancer: a review. Crit Rev Oncol Hematol 2005;56:365-78.