ABSTRACT
Most first relapses in patients with melanoma occur in regional lymph nodes basins. Such lesions are frequently diagnosed clinically during the first 2 y of follow-up. In the las few years, our group has been studying the usefulness of 99Tc-methoxy-isobutylisonitrile (MIBI) scintigraphy in the evaluation of recurrent melanoma lesions. The aim of the present study was to prospectively evaluate the clinical value of 99mTc-MIBI scintigraphy in the diagnosis of subclinical nodal metastases. Methods. We icnluded 66 patients within 3 mo of melanoma diagnosis, with Breslow thickness >1.0mm, all treated with wide local excision ofthe primary lesion. When 99mTc-MIBI scanning was performed, 49 of them did not have evidence of nodal disease, and 17 had clinically questionable regional lymph node lesions. Planar images of lymph node regions were acquired 10 min after injection, using a dose of 740-1.110 MBq and a large-fiel-of-view gamma camera equipped with a low-energy high-resolution collimator. Scan findings were confirmed by pathology of by clinical follow-up (median, 35 mo). Results: Thirty of 33 patients with regional lymph node metastases received a correct diagnosis, 14 with palpable lesions and 16 with nonpalpable lesions. In 3 cases the were initially 99mTc-MIBI negative, nodal metastases were found during follow-up. The following diagnostic values were calculated: sensitivity, 0.91 (95 percent confidence interval CI, 0.75-0.98); specificity, 0.85 (95 percent CI0.67-0.94); likelyhood ratio of a positive test 6.0 (95 percent CI 2.7-13.5); and likelyhood ratio of a negative test, 0.11 )95 percent CI 0.036-0.32). Conclusion: 99mTc-MIBI scanning may have a secondary role in the staging of regional lymph nodes in patients clinically localized melanoma who are not good candidates for sentinel node biopsy
Subject(s)
Technetium Tc 99m Sestamibi/diagnosis , Melanoma , Lymph Nodes , Bibliography, National , UruguayABSTRACT
99mTc-MIBI scintigraphy has been proposed as a technique that can diagnose clinically undetectable melanoma metastases. The aim of the study was to compare the sensitivity of 99mTc-MIBI with that of sentinel node biopsy (SNB) in the detection of nodal disease. Twenty-eight patients with melanoma <1.0mm thick were enrolled. Patients underwent 99mTc-MIBI scintigraphy and a preoperative lymphoscientigraphy followed by SNB. Sentinel nodes were identified in 27/28 patients. Twelve patients had an involved sentinel node (SN), being 99mTc-MIBI positive in 10. No patient with negative SNB developed regional recurrence during the study. 99mTc-MIBI had a sensitivity of 83 percent and a specificity of 93 percent. We conclude that SNB remains the procedure of choice for detecting subclinical lymph node involvement from melanoma. 99mTc-MIBI could have an alternative role in lymph node staging of patients who are not good candidates of SNB, that needs to be tested in appropriate trials
Subject(s)
Humans , Technetium Tc 99m Sestamibi/diagnosis , Melanoma/secondary , Lymph Nodes/diagnostic imaging , Bibliography, National , UruguaySubject(s)
INFORME DE CASO , Humans , Female , Cecal Neoplasms/diagnosis , Bibliography, National , UruguayABSTRACT
Two cases of malignant melanoma (primary and metastatic lesions) imaged with Tc-99m tetrofosmin are reported. One patient showed intense uptake in a primary skin lesion of the thorax, and the other patient had accumulation in skin, cerebellum, breast, and lymph node metastases. Like Tc-99m MIBI, Tc-99m tetrofosmin imaging may be of clinical relevance in the evaluation of suspicious skin lesions and in patients with known cutaneous malignant melanoma in the assessment of recurrent disease during follow-up evaluation