Differentiation of Pituitary Adenomas From Other Sellar and Parasellar Tumors by 99mTc(V)-DMSA Scintigraphy

Abstract

Pentavalent technetium-99m dimercaptosuccinic acid [ 99m Tc(V)-DMSA] scintigraphy was evaluated for the differentiation of pituitary adenomas, especially non-functioning adenomas, from other sellar and parasellar lesions. Diffuse 99m Tc(V)-DMSA accumulation within the tumor was found in seven of seven non-functioning, three of four growth hormone-secreting, and seven of eight prolactin-secreting adenomas, but only partial accumulation in only two of 16 non-pituitary adenomas and normal pituitary glands. There were no significant relationship between tumor-to-background ratios and tumor size or serum hormone level. 99m Tc(V)-DMSA scintigraphy showed overall sensitivity of 81% (17/21 cases) for detecting pituitary adenomas, in particular 100% for non-functioning adenomas. 99m Tc(V)-DMSA may be useful for detecting pituitary adenomas, especially non-functioning adenomas, and for the differentiation of non-functioning pituitary adenomas from other sellar and parasellar lesions.

Clinical usefulness of 99mTc-HYNIC-TOC, 99mTc(V)-DMSA, and 99mTc-MIBI SPECT in the evaluation of pituitary adenomas

“…Consistent with these findings are the results of a few studies indicating that the 99m Tc(V)-DMSA scintigraphy showed an overall sensitivity ranging from 71 to 95% in detecting PAs 43–45. Furthermore, 99m Tc-MIBI was found to have a strong affinity for PA, but not the normal pituitary gland 36,37.…”

“…Kunishio et al 38 suggest that 99m Tc-MIBI SPECT may be a useful technique for the diagnosis of PA, with an overall sensitivity of 85%. Accumulation of these tracers is generally related to the affinity for the tissue or lesions, not the size of the lesion 36,37,43–45, which was also the case in our study.…”

“…However, SPECT modality performed by a large field of view gamma camera enables the cross-sectional imaging of the pituitary region of the brain. An abnormal tracer accumulation in the sellar region could be considered a pathological finding 35,39,43. In our study, we detected seven (28%) of 25 microadenomas using 99m Tc-HYNIC-TOC SPECT, which were MRI negative.…”

“…Approximately 95% of benign and malignant primary brain tumors are detected by 99m Tc(V)-DMSA single photon emission computed tomography (SPECT) scans, such as low-grade or high-grade gliomas, meningiomas, and schwannomas 40–42. Several reports suggest that 99m Tc(V)-DMSA uptake by PAs is related to proliferative activity, which is either directly related to tumor grade or to the mitotic activity 43–45.…”

Dimercaptosuccinic acid: A multifunctional cost effective agent for imaging and therapy

“…The delayed uptake ratio, retention ratio, and retention index are higher for the malignant tumors as compared to the benign pathology. Tc-99m (V) DMSA also demonstrated superiority over Tl-201 imaging for primary and metastatic brain tumors[ 55 56 57 58 59 60 ] [ Table 2 ].…”