Solitary pulmonary nodule evaluation with^99mTc-methoxy isobutyl isonitrile in a tuberculosis-endemic area

Abstract

High prevalence of tuberculosis increases the odds for nonmalignant solitary pulmonary nodules (SPNs). Positron emission tomography (PET) using 18 F-fluorodeoxyglucose is the method of choice for the identification of malignant SPNs requiring curative surgery. However, PET is not widely available. Technetium-99m methoxy isobutyl isonitrile (MIBI) is inexpensive, widely available and shows increased uptake in malignant SPNs. The aim of the present study was to prospectively evaluate the diagnostic value of MIBI single photon emission computed tomography to distinguish between benign and malignant SPNs in a tuberculosis-endemic area.In total, 49 patients with radiologically indeterminate SPNs (single lesion f6 cm in diameter) were prospectively evaluated with MIBI. The final diagnosis was established with bronchoscopy, fine-needle aspiration, surgical resection or clinical follow-up for o2 yrs.A total of 12 (92%) out of 13 malignant lesions showed increased uptake of MIBI, while no uptake was observed in 33 (92%) out of 36 benign lesions. MIBI uptake indicated malignancy with a sensitivity and specificity of 92% and a negative predictive value of 97%.In this tuberculosis-endemic area, technetium-99m methoxy isobutyl isonitrile single photon emission computed tomography evaluation of solitary pulmonary nodules had a high negative predictive value. Therefore, it has the potential to prevent unnecessary surgical resections of benign nodules and serve as a low-cost alternative when positron emission tomography is not available.

Diagnostic utility of 99mTc-EDDA-tricine-HYNIC-Tyr3-octreotate SPECT for differentiation of active from inactive pulmonary tuberculosis

“…Other tracers such as 99m Tc-MIBI and 18 F-FDG PET also share the same limitation in the positive predictive value, and this limitation should always be borne in mind especially in the tuberculosis-endemic areas of the world [34,35].…”

The diagnostic accuracy of integrated positron emission tomography/computed tomography in the evaluation of pulmonary mass lesions in a tuberculosis-endemic area

“…[12] Only three studies have evaluated nuclear scanning to assess pulmonary mass lesions in SA. [6,13,14] Schuurmans et al [13] found a sensitivity of 92.3% and a specificity of 91.7% for the use of technetium 99m-methoxy isobutyl isonitrile as a marker for tumour uptake. Sathekge et al [6] performed a prospective study of 30 patients to assess the accuracy of dual time point PET-CT in the assessment of SPNs in Pretoria, SA.…”

Ultrathin bronchoscopy for solitary pulmonary lesions in a region endemic for tuberculosis: a randomised pilot trial

“…However, more than 95 % of SPL detected by low-dose CT screening show false positive findings due to a non-malignant final diagnosis [ 1 ]. In a tuberculosis (TB) endemic area, the prevalence of benign SPL may be even higher [ 2 ], and therefore efforts have been undertaken to establish diagnostic modalities to distinguish between malignant and benign lesions without excess perioperative mortality [ 3 ]. According to guidelines for the diagnosis of SPL, there are three possibilities to manage these patients depending on the probability of an underlying malignancy: serial CT scans, tissue biopsy, or direct surgical resection [ 4 ].…”