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Amyloid goitre: CT and MR findings
Clinical Radiology (1995) 50, 409-411
Amyloid Goitre: CT and MR Findings F. J. P. FONTAN, F. CORDIDO*, J. MOSQUERA, L. VALBUENAt and A. ATANES~
Departments of Radiology, *Endocrinology, ~fPathology and ~.Rheumatology, Hospital Juan Canalejo, La Coru~a, Spain Two cases of amyloid goitre presented as an enlarged thyroid mass with cystic components. Solid parts of the goitre showed high attenuation on computed tomography (CT) and moderate hypointensity on T1 and T2-weighted images. Fine needle aspiration was negative for amyloid, but pathological studies of surgical specimens demonstrated amyloid infiltration of the thyroid interstitium and regressive colloid cysts. In a patient at risk for systemic amyloidosis, thyroid enlargement with a cystic component suggests amyloid goitre. In this case, needle biopsies should be directed to solid areas of the mass because amyloid material may not be present in the cysts. Font/m, F.J.P., Cordido, F., Mosquera, J., Valbuena, L. & Atanes, A. (1995) Clinical Radiology 50, 409-411. Amyloid Goitre: CT and MR Findings
Accepted for Publication 23 January 1995
Systemic amyloidosis is often associated with microscopic deposits in the thyroid gland, but these deposits are rarely large enough to deserve the diagnosis of amyloid goitre. Here we compare the computed tomography (CT), magnetic resonance (MR) and histological findings in two such patients. CASE REPORTS Case 1. A 22-year-old woman with amyloidosis secondary to familial Mediterranean fever, presented with progressive thyroid swelling associated with shortness of breath and stridor. The patient had extensive gastrointestinal and renal amyloid infiltration, and had required a renal transplant 5 years previously. She had undergone partial thyroidectomy on two occasions, 6 and 4 years previously because of tracheal compression. The surgical specimens showed amyloid thyroid infiltration. Thyroid functional test were normal. Ultrasonography (US) showed a conglomerate of cystic lesions separated by hyperechogenic septa. There were liquid-liquid levels and solid material floating within some of the cysts. CT (Fig. I a) demonstrated a large thyroid mass containing cysts separated by fine septa of tissue, which enhanced markedly following i.v. contrast. MR using a 0.5 Tesla magnet (Fig. lb) showed a similarly heterogeneous structure, with hyperintense areas in T1 and T2-weighted images separated by hypointense septa. Some of the masses were hypointense on T1 and T2-weighted acquisitions, perhaps reflecting the presence of old haemorrhage. Both CT and MR showed marked tracheal compression. Fine needle aspiration confirmed the intracystic haemorrhage, but showed no evidence of amyloid. The patient underwent surgical resection of the mass. Pathology revealed that the cysts were filled with colloid and sometimes haemorrhagic material. The interstitium and vessels around the cysts were infiltrated by amyloid.
Case 2. A 66-year-old woman with colonic amyloidosis secondary to advanced rheumatoid arthritis, developed progressive thyroid enlargement with dysphonia and stridor. Thyroid function tests were normal. US showed a large hyperechogenic mass consisting of cystic areas with occasional septa. CT (Fig. 2a) showed marked thyroid enlargement with cystic non-enhancing areas surrounded by hyperdense tissue which enhanced markedly after contrast. On MR (Fig. 2b) the cysts appeared markedly hyperintense on T1 and T2-weighted images, while the solid areas showed some hypointensity in T1 and T2-weighted sequences. Unguided fine needle aspiration of the thyroid mass showed no sign of Correspondence to Dr F. Javier P6rez Fontfin, Servicio Radiologia, Hospital Juan Canalejo, Xubias de Arriba, 84, 15006, La Corufia, Spain. 9 1995 BlackwellScienceLimited.
amyloid infiltration. The patient underwent surgical removal of the mass. Pathological study showed amyloid infiltration of the interstitium. The cysts, however, represented dilated follicles filled with colloid and without amyloid.
DISCUSSION Amyloidosis comprises a diverse collection of diseases characterized by the presence of extracellular deposits of insoluble, fibrillar, proteinaceous material with a welldefined, beta-pleated sheet ultrastructure [1]. Systemic amyloidosis is often associated with microscopic deposits in the thyroid gland, but amyloid goitre is a clinical rarity [2]. The fatty infiltration that usually accompanies amyl0id infiltration causes hyperechogenicity on US and a diffuse decrease in the CT attenuation [2]. Recent reports [3,4], our own experience with these two patients and the already published case [5] of a child with Still's disease, share a common radiological presentation. The most striking features in these cases were the marked thyroid enlargement and the presence of cystic lesions which appeared as discrete hypodense masses on CT with very high signal intensity on T1 and T2weighted images. Some cysts were hyperdense on CT scan and hypointense on M R sequences, sometimes with internal liquid-liquid levels due to spontaneous bleeding. Percutaneous aspiration of the cysts and subsequent pathological study of the surgical specimens demonstrated follicles markedly distended with colloid and haemorrhage. We believe that the presence of cysts represents a common response of the thyroid secondary to interstitial amyloid infiltration. In this regard, case 1, in which the thyroid appeared as a cystic mass with only scattered septa of solid tissue infiltrated by amyloid, may be the ultimate expression of the process. Fine needle aspiration can be diagnostic [2], but this was not the case in our patients, perhaps because the samples were obtained from cystic areas. Because amyloid is mainly present in solid areas, needle aspiration must be guided to these zones. Despite being infiltrated by amyloid, the noncystic component of the goitre, showed the characteristic high attenuation of thyroid tissue, with marked enhancement
410
CLINICALRADIOLOGY
(a)
(a)
(b) Fig. 2 (a) CT scan shows cystic non-enhancing areas surrounded by enhancing tissue. (b) Axial M R Tl-weighted image shows cysts as markedly hyperintense nodules, while solid areas appeared moderately hypointense.
(b) Fig. 1 - (a) CT scan shows a large mass composed of cystic areas separated by septa of tissue which enhanced markedly after the injection of i.v. contrast. (b) Axial Tl-weighted M R image shows most of the cysts as hyperintense masses, while some are hypointense reflecting old haemorrhage.
after contrast. This finding is consistent with the preservation of normal thyroid function. M R of solid areas in case 2 showed a moderately hypointense signal in T1 and T2-weighted images. This has been considered
a characteristic finding by some [1], but not all authors [4]. The global cystic transformation of the thyroid in case 1 was very peculiar, and differed from the appearance of other thyroid processes. The association of solid and systic areas, as observed in case 2 and previous reports [3-5] shares radiological features with more common processes, such as adenomatous goitre [3,6]. In instances like these, the diagnosis must also be based on clinical considerations (e.g. risk factors, rapidly growing mass, or systemic amyloidosis). In a patient at risk for systemic amyloidosis, the presence of thyroid enlargement with cystic components suggests amyloid goitre. Both CT and M R can show the involvement of the thyroid and neighbouring organs including secondary tracheal compression. Histological studies must be directed to solid areas of the lesion. 9 1995 Blackwell Science Ltd, Clinical Radiology, 50, 409 411.
AMYLOID GOITRE REFERENCES 1 Gean-Marton AD, Kirsch CFE, Vezina LG et al. Focal amyloidosis of the head and neck: evaluation with CT and MR imaging. Radiology 1991;181:521-525. 2 Miyake H, Maeda H, Isomoto I e t al. Computed tomography in amyloid goiter. Journal of Computer Assisted Tomography 1988; 12:621-622. 3 Hatabu H, Iida Y, Kasagi K et al. Amyloid goiter: radiologic findings (letter). American Journal of Roentgenology 1990;155:193.
9 1995 BlackwellScienceLtd, Clinical Radiology, 50, 409-411.
411
4 Mache C J, Schwinghandl J, Riccabona M et al. Ultrasound and MRI findings in a case of childhood amyloid goiter. Pediatric Radiology 1993;23:565-566. 5 P~rez Fontfin FJ, Mosquera Os~s J, Pombo Felipe F et al. Amyloid goiter in a child-US, CT and MR evaluation. Pediatric Radiology 1992;22:393-394. 6 Noma S, Nishimura K, Togashi K. Thyroid gland: MR imaging. Radiology 1987;164:495-499,
Amyloid Goitre: CT and MR Findings F. J. P. FONTAN, F. CORDIDO*, J. MOSQUERA, L. VALBUENAt and A. ATANES~
Departments of Radiology, *Endocrinology, ~fPathology and ~.Rheumatology, Hospital Juan Canalejo, La Coru~a, Spain Two cases of amyloid goitre presented as an enlarged thyroid mass with cystic components. Solid parts of the goitre showed high attenuation on computed tomography (CT) and moderate hypointensity on T1 and T2-weighted images. Fine needle aspiration was negative for amyloid, but pathological studies of surgical specimens demonstrated amyloid infiltration of the thyroid interstitium and regressive colloid cysts. In a patient at risk for systemic amyloidosis, thyroid enlargement with a cystic component suggests amyloid goitre. In this case, needle biopsies should be directed to solid areas of the mass because amyloid material may not be present in the cysts. Font/m, F.J.P., Cordido, F., Mosquera, J., Valbuena, L. & Atanes, A. (1995) Clinical Radiology 50, 409-411. Amyloid Goitre: CT and MR Findings
Accepted for Publication 23 January 1995
Systemic amyloidosis is often associated with microscopic deposits in the thyroid gland, but these deposits are rarely large enough to deserve the diagnosis of amyloid goitre. Here we compare the computed tomography (CT), magnetic resonance (MR) and histological findings in two such patients. CASE REPORTS Case 1. A 22-year-old woman with amyloidosis secondary to familial Mediterranean fever, presented with progressive thyroid swelling associated with shortness of breath and stridor. The patient had extensive gastrointestinal and renal amyloid infiltration, and had required a renal transplant 5 years previously. She had undergone partial thyroidectomy on two occasions, 6 and 4 years previously because of tracheal compression. The surgical specimens showed amyloid thyroid infiltration. Thyroid functional test were normal. Ultrasonography (US) showed a conglomerate of cystic lesions separated by hyperechogenic septa. There were liquid-liquid levels and solid material floating within some of the cysts. CT (Fig. I a) demonstrated a large thyroid mass containing cysts separated by fine septa of tissue, which enhanced markedly following i.v. contrast. MR using a 0.5 Tesla magnet (Fig. lb) showed a similarly heterogeneous structure, with hyperintense areas in T1 and T2-weighted images separated by hypointense septa. Some of the masses were hypointense on T1 and T2-weighted acquisitions, perhaps reflecting the presence of old haemorrhage. Both CT and MR showed marked tracheal compression. Fine needle aspiration confirmed the intracystic haemorrhage, but showed no evidence of amyloid. The patient underwent surgical resection of the mass. Pathology revealed that the cysts were filled with colloid and sometimes haemorrhagic material. The interstitium and vessels around the cysts were infiltrated by amyloid.
Case 2. A 66-year-old woman with colonic amyloidosis secondary to advanced rheumatoid arthritis, developed progressive thyroid enlargement with dysphonia and stridor. Thyroid function tests were normal. US showed a large hyperechogenic mass consisting of cystic areas with occasional septa. CT (Fig. 2a) showed marked thyroid enlargement with cystic non-enhancing areas surrounded by hyperdense tissue which enhanced markedly after contrast. On MR (Fig. 2b) the cysts appeared markedly hyperintense on T1 and T2-weighted images, while the solid areas showed some hypointensity in T1 and T2-weighted sequences. Unguided fine needle aspiration of the thyroid mass showed no sign of Correspondence to Dr F. Javier P6rez Fontfin, Servicio Radiologia, Hospital Juan Canalejo, Xubias de Arriba, 84, 15006, La Corufia, Spain. 9 1995 BlackwellScienceLimited.
amyloid infiltration. The patient underwent surgical removal of the mass. Pathological study showed amyloid infiltration of the interstitium. The cysts, however, represented dilated follicles filled with colloid and without amyloid.
DISCUSSION Amyloidosis comprises a diverse collection of diseases characterized by the presence of extracellular deposits of insoluble, fibrillar, proteinaceous material with a welldefined, beta-pleated sheet ultrastructure [1]. Systemic amyloidosis is often associated with microscopic deposits in the thyroid gland, but amyloid goitre is a clinical rarity [2]. The fatty infiltration that usually accompanies amyl0id infiltration causes hyperechogenicity on US and a diffuse decrease in the CT attenuation [2]. Recent reports [3,4], our own experience with these two patients and the already published case [5] of a child with Still's disease, share a common radiological presentation. The most striking features in these cases were the marked thyroid enlargement and the presence of cystic lesions which appeared as discrete hypodense masses on CT with very high signal intensity on T1 and T2weighted images. Some cysts were hyperdense on CT scan and hypointense on M R sequences, sometimes with internal liquid-liquid levels due to spontaneous bleeding. Percutaneous aspiration of the cysts and subsequent pathological study of the surgical specimens demonstrated follicles markedly distended with colloid and haemorrhage. We believe that the presence of cysts represents a common response of the thyroid secondary to interstitial amyloid infiltration. In this regard, case 1, in which the thyroid appeared as a cystic mass with only scattered septa of solid tissue infiltrated by amyloid, may be the ultimate expression of the process. Fine needle aspiration can be diagnostic [2], but this was not the case in our patients, perhaps because the samples were obtained from cystic areas. Because amyloid is mainly present in solid areas, needle aspiration must be guided to these zones. Despite being infiltrated by amyloid, the noncystic component of the goitre, showed the characteristic high attenuation of thyroid tissue, with marked enhancement
410
CLINICALRADIOLOGY
(a)
(a)
(b) Fig. 2 (a) CT scan shows cystic non-enhancing areas surrounded by enhancing tissue. (b) Axial M R Tl-weighted image shows cysts as markedly hyperintense nodules, while solid areas appeared moderately hypointense.
(b) Fig. 1 - (a) CT scan shows a large mass composed of cystic areas separated by septa of tissue which enhanced markedly after the injection of i.v. contrast. (b) Axial Tl-weighted M R image shows most of the cysts as hyperintense masses, while some are hypointense reflecting old haemorrhage.
after contrast. This finding is consistent with the preservation of normal thyroid function. M R of solid areas in case 2 showed a moderately hypointense signal in T1 and T2-weighted images. This has been considered
a characteristic finding by some [1], but not all authors [4]. The global cystic transformation of the thyroid in case 1 was very peculiar, and differed from the appearance of other thyroid processes. The association of solid and systic areas, as observed in case 2 and previous reports [3-5] shares radiological features with more common processes, such as adenomatous goitre [3,6]. In instances like these, the diagnosis must also be based on clinical considerations (e.g. risk factors, rapidly growing mass, or systemic amyloidosis). In a patient at risk for systemic amyloidosis, the presence of thyroid enlargement with cystic components suggests amyloid goitre. Both CT and M R can show the involvement of the thyroid and neighbouring organs including secondary tracheal compression. Histological studies must be directed to solid areas of the lesion. 9 1995 Blackwell Science Ltd, Clinical Radiology, 50, 409 411.
AMYLOID GOITRE REFERENCES 1 Gean-Marton AD, Kirsch CFE, Vezina LG et al. Focal amyloidosis of the head and neck: evaluation with CT and MR imaging. Radiology 1991;181:521-525. 2 Miyake H, Maeda H, Isomoto I e t al. Computed tomography in amyloid goiter. Journal of Computer Assisted Tomography 1988; 12:621-622. 3 Hatabu H, Iida Y, Kasagi K et al. Amyloid goiter: radiologic findings (letter). American Journal of Roentgenology 1990;155:193.
9 1995 BlackwellScienceLtd, Clinical Radiology, 50, 409-411.
411
4 Mache C J, Schwinghandl J, Riccabona M et al. Ultrasound and MRI findings in a case of childhood amyloid goiter. Pediatric Radiology 1993;23:565-566. 5 P~rez Fontfin FJ, Mosquera Os~s J, Pombo Felipe F et al. Amyloid goiter in a child-US, CT and MR evaluation. Pediatric Radiology 1992;22:393-394. 6 Noma S, Nishimura K, Togashi K. Thyroid gland: MR imaging. Radiology 1987;164:495-499,