Accuracy of parathyroid imaging: comparison of planar scintigraphy, spect, spect/ct and c-11 methionine pet for the detection of parathyroid adenomas and glandular hyperplasia

Abstract

Sporadic primary hyperparathyroidism is the most common cause of hypercalcemia in the outpatient population, with a prevalence of one per 500 women and one per 2000 men over 40 years of age. Both increased cell proliferative activity and a decreased sensitivity of cells to secretory inhibition by calcium occur in hyperparathyroidism (1). The diagnosis of hyperparathyroidism is usually made by the demonstration of an inappropriately elevated parathyroid hormone level compared to the simultaneously measured serum calcium level (2). In 80% to 85% of patients, primary hyperparathyroidism is caused by one or more parathyroid adenomas, and in 15% to 20% of cases, it is the result of parathyroid hyperplasia. A rare cause of primary hyperparathyroidism, accounting for less than 1% of all cases, is parathyroid carcinoma. Persistent hyperparathyroidism occurs in 5% to 10% of all patients who undergo surgery for primary hyperparathyroidism, with a continuation of the pre-operative hypercalcemia in the immediate post-operative period. Hyperparathyroidism that presents after a period of more than six months of normocalcemia following surgery is called "recurrent hyperparathyroidism" and is commonly due to continuing growth of the remaining parathyroid glands (3). Secondary hyperparathyroidism is a compensatory hypertrophy of all parathyroid glands due to hypocalcemia, as occurs in renal failure or with vitamin D deficiency (4), whereas tertiary hyperparathyroidism describes the development of autonomous function of parathyroid tissue after longstanding secondary hyperparathyroidism (5-8).In most cases (80%-85%), parathyroid adenomas are found adjacent to the thyroid gland, which is the normal location for these adenomas. However, in up to 20% of cases, they are ectopically placed, e.g., in the anterosuperior, posterosuperior, or very rarely in the mid-lower mediastinum. Occasionally, parathyroid adenomas may be found within, or lateral to, the carotid sheath. Rarely, the lower parathyroid glands fail to migrate, remaining in the high neck anterior to the carotid bifurcation. Finally, 1.4% to 3.2% of all parathyroid adenomas are intrathyroidal, i.e., embedded completely within the thyroid gland (9).Among the several imaging procedures that have been developed for the detection and localization of parathyroid adenomas, dual-phase scintigraphy with Tc-99m sestamibi combined with ultrasonography is considered the imaging method of choice for pre-operatively localizing parathyroid adenomas. The overall accuracy of dual-phase scintigraphy combined with ultrasonography has been found to be superior to that of other scintigraphic or radiological techniques (10, 11). Studies comparing planar imaging and single photon emission computed tomography (SPECT) have shown significantly increased sensitivity for Tc-99m sestamibi SPECT, thus supporting its routine use prior to surgery (12-14). HEAD AND NECK IMAGING PURPOSETo compare the accuracy of planar scintigraphy, single photon emission computed tomography (SPECT), SPECT-CT, and positron...

Detection and Characterization of Parathyroid Adenoma/Hyperplasia for Preoperative Localization: Comparison Between 11C-Methionine PET/CT and 99mTc-Sestamibi Scintigraphy

“…This result agreed with the correlation between maximum standardized uptake value (SUV max ) of Met-PET/CT and sPTH reported by Otto et al [16] even though SUVR was used instead of SUV max in the current study. In addition, Met-PET/CT could detect and localize parathyroid tissues in the lesions of negative on MIBI scintigraphy, which was also consistent with the previous reports [22,23]. From our data and other reports, it seems to be apparent that Met-PET/CT is more useful for detection and localization of abnormal parathyroid tissue than MIBI scintigraphy.…”

Rak przytarczycy jako przedoperacyjny dylemat diagnostyczny – opis przypadku i przegląd piśmiennictwa

“…Using this technique, several imaging signs have been proposed to raise the suspicion of PC [11,12,16,18,23,25]. The PC diagnosis confirms the histopathological evaluation.…”

“…This option has emerged as a powerful imaging tool for the detection of various lesions with increased metabolic acti vity. Due to costs and limited availability, this method is used in cases with a negative 99mTc-Sestamibi scan [11,12].…”

The use of positron emission tomography with 11C-methionine in patients with primary hyperparathyroidism

“…The single photon emission computed tomography (SPECT) may be helpful for giving a more precise localization of enlarged parathyroid gland(s). The sensitivity varies in different series and may reach 90-95 % using SPECT, but may be lower using planar scintigraphy [6]. The sensitivity for small adenomas, double adenomas or hyperplasia is much lower, and in the latter case computed tomography (CT)-sestamibi SPECT image fusion is superior to CT or sestamibi SPECT alone [7].…”

“…Most of the studies are retrospective, include small series, some use C-Met-PET alone and other C-Met PET/CT. Most, but no all studies, suggest that PET has a higher sensitivity than either planar 99m Tc sestamibi or SPECT in patients with newly diagnosed PHPT [6], and persistent and recurrent PHPT [10,11].…”