Comparison of iodine-123 metaiodobenzylguanidine (MIBG) scan and [18F]fluorodeoxyglucose positron emission tomography to evaluate response after iodine-131 MIBG therapy for relapsed neuroblastoma.

PURPOSE: Children with relapsed neuroblastoma have poor survival. It is crucial to have a reliable method for evaluating functional response to new therapies. In this study, we compared two functional imaging modalities for neuroblastoma: metaiodobenzylguanidine (MIBG) scan for uptake by the norepinephrine transporter and [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) uptake for glucose metabolic activity. PATIENTS AND METHODS: Patients enrolled onto a phase I study of sequential infusion of iodine-131 ((131)I) MIBG (NANT-2000-01) were eligible for inclusion if they had concomitant FDG-PET and MIBG scans. (131)I-MIBG therapy was administered on days 0 and 14. For each patient, we compared all lesions identified on concomitant FDG-PET and MIBG scans and gave scans a semiquantitative score. RESULTS: The overall concordance of positive lesions on concomitant MIBG and FDG-PET scans was 39.6% when examining the 139 unique anatomic lesions. MIBG imaging was significantly more sensitive than FDG-PET overall and for the detection of bone lesions (P < .001). There was a trend for increased sensitivity of FDG-PET for detection of soft tissue lesions. Both modalities showed similar improvement in number of lesions identified from day 0 to day 56 scan and in semiquantitative scores that correlated with overall response. FDG-PET scans became completely negative more often than MIBG scans after treatment. CONCLUSION: MIBG scan is significantly more sensitive for individual lesion detection in relapsed neuroblastoma than FDG-PET, though FDG-PET can sometimes play a complementary role, particularly in soft tissue lesions. Complete response by FDG-PET metabolic evaluation did not always correlate with complete response by MIBG uptake.

Intravenous bisphosphonate-related osteonecrosis of the jaw: bone scintigraphy as an early indicator.

PURPOSE: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is recognized as a serious complication among patients receiving bisphosphonate therapy. However, methods for early detection and identification of patients at risk for osteonecrosis of the jaw (ONJ) need further investigation. The purpose of this study was to characterize BRONJ among patients receiving intravenous bisphosphonates and to examine bone scintigraphy findings that preceded manifestation of frank ONJ. MATERIALS AND METHODS: We identified all known cases of BRONJ (defined according to 2006 American Association of Oral and Maxillofacial Surgeons criteria) diagnosed between January 2004 and September 2008 among patients who received intravenous bisphosphonate therapy (IVBP). The medical records were abstracted, and the clinical and radiographic features of BRONJ and relevant comorbidities were characterized. Technetium Tc 99 bone scintigrams were systematically reviewed among the subset of patients who received these imaging studies for oncologic care and imaging findings were correlated with the temporal development of ONJ. RESULTS: We identified 59 cases of intravenous BRONJ (median age, 61.4 +/- 10.7 years; 57.6% female), of whom 44.1% had breast cancer, 33.9% had multiple myeloma, and the remainder had metastatic prostate cancer (15.3%) or other cancers (6.8%). One third (32.2%) of the cohort was diabetic. In addition to IVBP, the vast majority (86.4%) had also received prior systemic glucocorticoid therapy. The median cumulative number of IVBP doses was 25 (interquartile range, 16-39) at the time of BRONJ diagnosis. Half of the patients had prior invasive dental procedures; ONJ developed spontaneously in 27.1%, and in the remainder ONJ developed in the setting of periodontal disease (10.1%) or local trauma (8.4%). Most patients presented with painful stage 2 disease involving the mandible (75%), and Actinomyces was present in more than 77% of available histologic specimens. During the median follow-up of 1.5 years, 15 patients (25.4%) regressed to a less severe stage, with healing in 6 patients; 16 (27.1%) worsened; and the remainder stayed within the same stage, but in almost half of these patients, the extent of involvement progressed. Of the 38 patients who had 99Tc bone scintigraphy, 35 had bone scans before development of BRONJ, and among these patients, 23 (67.5%) had positive tracer uptake in areas that subsequently developed BRONJ. CONCLUSIONS: In this study bone scintigraphy showed positive tracer uptake before the development of BRONJ in almost 66% of patients who had these scans before clinical evidence of frank osteonecrosis. BRONJ subsequently developed in the areas identified on scintigraphy in these patients. Further studies should explore the role of bone scintigraphy in the detection of early subclinical BRONJ.

Calciphylaxis and bone scintigraphy: case report with histological confirmation and review of the literature.

We present a patient with a history of end-stage renal disease, who developed skin lesions in the bilateral calves a month after the initiation of hemodialysis. The lesions were biopsied, and the histological findings were consistent with a diagnosis of calciphylaxis. The patient had a baseline pretreatment bone scan that showed extensive systemic disease. The patient died 20 days after the imaging study. A review of the literature on bone scans and calciphylaxis is presented.