Influence of thyroid disease in diagnostic accuracy of Tc99m-sestamibi scintigraphy in patients with primary hyperparathyroidism (PHP)
Nerea Egaña, Miguel Paja, Maria Teresa Gutierrez, Maria Luisa Rodriguez, Fernando Goñi, Estibaliz Ugarte & Javier Espiga
Bilateral cervical exploration has been the gold standard in parathyroid surgery. Nowadays, the preoperative localization procedures have facilitated the minimally invasive surgery. This study aims to analyze the influence of thyroid disease in Tc99m-sestamibi scintigraphy (MIBI) results.
A series of 154 patients with PHP who underwent parathyroidectomy was reviewed. Patients were divided into two groups: group 1 (G1, 58 patients) with thyroid diseases, and group 2 (G2, 96 patients) without goiter or thyroid nodules. Predictive positive value (PPV) of the MIBI was defined as true positive results (when the pathologic gland was correctly localized)/true positive+false positive (when no pathologic gland was found).
Results: There was no difference between two groups in sex, age and most of the preoperative biochemical parameters.
Histopathology showed 143 (93%) single adenomas (G1=51, G2=92), 3 carcinomas (two in G1), 5 hyperplastic (three in G1), and 3 double adenomas (two in G1).
The PPV of MIBI in G1 was 65% (26/26+12) and in G2, 85% (69/69+12); P=0.003.
Since minimally invasive surgery is performed, the preoperative localization procedures have become very important, particularly MIBI. Because the presence of thyroid nodules reduces the sensitivity of MIBI, patients with HPT should ruled out coexistent thyroid disease.