Sestamibi scintigraphy, topography, and histopathology of parathyroid glands in secondary hyperparathyroidism.
BACKGROUND
Several imaging techniques presently are available to assess the location of hyperplastic parathyroid glands. The purpose of the present study is to assess the place of dual-phase technetium Tc 99m-sestamibi (MIBI) scintigraphy in the preoperative localization of hyperplastic parathyroid glands in patients with severe secondary hyperparathyroidism (SHPT).


METHODS
We studied 35 consecutive adult white hemodialysis patients undergoing a first parathyroidectomy after performing MIBI scintigraphy. Hyperplasia of the parathyroid glands was classified as diffuse (DH) or nodular (NH). Statistical analysis was conducted by comparing patients with MIBI-negative (no focal area of increased uptake) with MIBI-positive (> or = 1 focal area of increased uptake) results and stratifying parathyroid glands according to location (superior and inferior).


RESULTS
MIBI scintigraphy showed focal areas of increased uptake in at least 1 gland in 25 patients (71.4%). Total number of focal areas of increased uptake was 42 of 121 glands removed (sensitivity, 34.7%; specificity, 100%). One hundred one glands showed NH and 20 glands showed DH. The 25 patients with MIBI-positive results had 85 pathological glands removed, and the 10 patients with MIBI-negative results had 36 pathological glands removed: in the former, most glands showed NH (77 of 85 glands; 90.6%), and in the latter, 24 of 36 glands showed NH (66.7%; P = 0.004 at chi-square test). The sensitivity of MIBI scintigraphy for distinguishing specific subtypes of hyperplasia was 37.6% (38 of 101 glands) for NH and 20.0% (4 of 20 glands) for DH (P = 0.0005). The following values were significantly greater in inferior compared with superior glands: (1) estimated weight (2.1 +/- 0.8 versus 1.6 +/- 1.2 g; P = 0.04), (2) percentage of MIBI positivity (34 of 42 inferior glands [80.9%] versus 8 of 42 superior glands [19.1%]; P = 0.0001), and (3) percentage of localization permitted by MIBI scintigraphy (34 of 63 inferior glands [54.0%] versus 8 of 58 superior glands [13.8%]; P = 0.0001). Thus, NH, although equally distributed between inferior (53 of 63 glands) and superior (48 of 58 glands) glands, showed a percentage of MIBI positivity significantly greater in inferior (34 of 53 glands [64.1%]) compared with superior glands (8 of 48 glands [16.7%]; P = 0.0001).


CONCLUSIONS
MIBI scintigraphy did not show high sensitivity in identifying hyperplastic glands, although it was able to identify those with NH better than those with DH. Thus, MIBI scintigraphy has limited value preoperatively for patients with SHPT. Estimated weight, percentage of MIBI positivity, and percentage of localization permitted by MIBI scintigraphy were significantly greater in inferior glands.
Lomonte
Carlo
C
Division of Nephrology, Miulli General Hospital, Acquaviva delle Fonti, Italy.
Buonvino
Nicola
N
Selvaggiolo
Michele
M
Dassira
Mario
M
Grasso
Giovanni
G
Vernaglione
Luigi
L
Basile
Carlo
C
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D006965:Hyperplasia / Q000175:diagnosis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000000981:diagnostic imaging* / Q000473:pathology*; D016105:Parathyroidectomy; D011877:Radionuclide Imaging / Q000379:methods; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D006435:Renal Dialysis; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics
D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi