Challenges of fracture risk assessment in Asian and Black women.

OBJECTIVES: Bone mineral density (BMD) and fracture risk calculators (eg, the Fracture Risk Assessment Tool [FRAX]) guide primary prevention care in postmenopausal women. BMD scores use non-Hispanic White (NHW) reference data for T-score classification, whereas FRAX incorporates BMD, clinical risk factors, and population differences when calculating risk. This study compares findings among Asian, Black, and NHW women who underwent osteoporosis screening in a US health care system. STUDY DESIGN: Retrospective cross-sectional study. METHODS: Asian, Black, and NHW women aged 65 to 75 years who underwent BMD testing (with no recent fracture, osteoporosis therapy, metastatic cancer, multiple myeloma, metabolic bone disorders, or kidney replacement therapy) were compared across the following measures: femoral neck BMD (FN-BMD) T-score (normal ≥ -1, osteoporosis ≤ -2.5), high FRAX 10-year hip fracture risk (FRAX-Hip ≥ 3%), FRAX risk factors, and diabetes status. RESULTS: Among 3640 Asian women, 23.8% had osteoporosis and 8.7% had FRAX-Hip scores of at least 3% (34.5% among those with osteoporosis). Among 11,711 NHW women, 12.3% had osteoporosis and 17.2% had FRAX-Hip scores of at least 3% (84.8% among those with osteoporosis). Among 1711 Black women, 68.1% had normal FN-BMD, 4.1% had BMD-defined osteoporosis, and 1.8% had FRAX-Hip scores of at least 3% (32.4% among those with osteoporosis). Fracture risk factors differed by group. Diabetes was 2-fold more prevalent in Black and Asian (35% and 36%, respectively) vs NHW (16%) women. CONCLUSIONS: A large subset of Asian women have discordant BMD and FRAX scores, presenting challenges in osteoporosis management. Furthermore, FN-BMD and especially FRAX scores identified few Black women at high fracture risk warranting treatment. Studies should examine whether fracture risk assessment can be optimized in understudied racial minority populations, particularly when findings are discordant.

Bone Mineral Density in Older U.S. Filipino, Chinese, Japanese, and White Women.

BACKGROUND/OBJECTIVES: Bone mineral density (BMD) reference data exist for U.S. White, Black, and Hispanic (Mexican American) populations but not for U.S. Asians. Few studies have compared BMD findings among different U.S. Asian ethnicities. DESIGN: Retrospective observational study. SETTING: Large northern California healthcare system. PARTICIPANTS: Asian and White women aged 50 to 79 years with BMD testing from 1998 to 2017 excluding those with estrogen or osteoporosis treatment, recent fracture, or select disorders affecting skeletal health. MEASUREMENTS: Femoral neck (FN)-BMD and height data. METHODS: Differences in FN-BMD were examined by ethnicity and age, comparing Filipino, Chinese, and Japanese women and non-Hispanic White women. Differences in BMD were also examined after adjustment for height. RESULTS: There were 37,224 Asian women (including 11,147 Filipino, 10,648 Chinese, and 2,519 Japanese) and 115,318 non-Hispanic White women. Mean height was similar among the Asian subgroups and about 6 to 8 cm lower than Whites. Mean FN-BMDs differed by less than 3% for Filipino, Chinese, and Japanese and all were lower than Whites, with smaller Asian-White differences among younger women (<3%; ages 50-59) and larger differences among older women (6-8%; ages 65-79). Adjusting FN-BMD for height reduced White-Asian differences by about 30% to 40%. CONCLUSION: Mean FN-BMD and height for Filipino, Chinese, and Japanese women were similar but consistently lower than White women, especially among older women. Although Asian-White BMD differences were substantially attenuated after height adjustment; some differences persisted for older women. Future studies should investigate potential age-cohort effects and the extent to which these BMD differences influence fracture risk and clinical care.

Unilateral vocal cord paralysis causes contralateral false-positive positron emission tomography scans of the larynx.

Positron emission tomography (PET) is used in the management of head and neck cancers. It identifies tissue with increased metabolic activity and is not specific for malignancy. A false-positive PET scan of the larynx is associated with vocal cord paralysis. We reviewed PET scan reports of patients with lung cancer from 1998 to 2001 to identify patients with increased 18-fluoro-2-deoxyglucose uptake in the larynx without a known history of head and neck cancer and then correlated this increased uptake with laryngoscopic findings. There were 17 patients who had a positive PET finding in the larynx. Fifteen of those had a false-positive PET scan in the larynx. All had contralateral vocal cord paralysis. Two patients were noted to have head and neck cancer. We conclude that vocal cord paralysis can cause a false-positive PET scan on the contralateral side of the larynx due to overactivity of laryngeal muscles that compensate for the paralyzed cord.

FDG uptake in brown adipose tissue mimicking an adrenal metastasis: source of false-positive interpretation.

Brown adipose tissue (BAT) uptake of F-18 fluorodeoxyglucose (FDG) poses a significant challenge to positron emission tomography interpretation. BAT is not only localized to the supraclavicular areas, but is also seen in the neck, mediastinum, axillae, costovertebral junctions, and retrocrural and periadrenal regions. We illustrate a case of typical supraclavicular BAT uptake in association with a discrete right adrenal region focus. On repeat study after diazepam administration, both the supraclavicular and periadrenal uptake were abolished. BAT uptake is an important cause of false-positives; when typical supraclavicular BAT uptake is seen, abnormalities in other areas of BAT distribution should be viewed with caution.

Dual-modality imaging of cancer with SPECT/CT.

Dual-modality imaging is an in vivo diagnostic technique that obtains structural and functional information directly from patient studies in a way that cannot be achieved with separate imaging systems alone. Dual-modality imaging systems are configured by combining computed tomography (CT) with radionuclide imaging (using positron emission tomography (PET) or single-photon emission computed tomography (SPECT)) on a single gantry which allows both functional and structural imaging to be performed during a single imaging session without having the patient leave the imaging system. A SPECT/CT system developed at UCSF is being used in a study to determine if dual-modality imaging offers advantages for assessment of patients with prostate cancer using (111)In-ProstaScint, a radiolabeled antibody for the prostate-specific membrane antigen. (111)In-ProstaScint images are reconstructed using an iterative maximum-likelihood expectation-maximization (ML-EM) algorithm with correction for photon attenuation using a patient-specific map of attenuation coefficients derived from CT. The ML-EM algorithm accounts for the dual-photon nature of the 111In-labeled radionuclide, and incorporates correction for the geometric response of the radionuclide collimator. The radionuclide image then can be coregistered and overlaid in color on a grayscale CT image for improved localization of the functional information from SPECT. Radionuclide images obtained with SPECT/CT and reconstructed using ML-EM with correction for photon attenuation and collimator response improve image quality in comparison to conventional radionuclide images obtained with filtered backprojection reconstruction. These results illustrate the potential advantages of dual-modality imaging for improving the quality and the localization of radionuclide uptake for staging disease, planning treatment, and monitoring therapeutic response in patients with cancer.

Malignant pleural mesothelioma: evaluation with CT, MR imaging, and PET.

Imaging plays an essential role in the evaluation of malignant pleural mesothelioma (MPM). Computed tomography is the primary imaging modality used for the diagnosis and staging of MPM. Magnetic resonance (MR) imaging and, more recently, positron emission tomography (PET) have emerged as modalities that can provide additional important diagnostic and prognostic information to help further delineate the extent of disease, especially in surgical candidates. Use of MR imaging performed with different pulse sequences and gadolinium-based contrast material can improve the detection of tumor extension, especially to the chest wall and diaphragm. PET can provide both anatomic and metabolic information, especially in cases of extrathoracic and mediastinal nodal metastasis. Each imaging modality has its advantages and limitations, but their combined use is crucial in determining the most appropriate treatment options for patients with MPM.

Detection of recurrent cervical cancer by whole-body FDG PET scan in asymptomatic and symptomatic women.

OBJECTIVE: To determine the ability of whole-body [(18)F]fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) scan to detect recurrent cervical carcinoma in both symptomatic and asymptomatic women. MATERIALS AND METHODS: We retrospectively reviewed the records of 44 women previously treated for cervical cancer who underwent 47 posttreatment whole-body FDG PET scans in an attempt to detect recurrent disease. Twenty-six scans were performed in asymptomatic women, whereas 21 scans were performed in women with symptoms suggestive of recurrence. RESULTS: About 30.8% of asymptomatic women had recurrent disease detected by PET scan compared to 66.7% of women in the symptomatic group. The sensitivity of PET scan for recurrent disease in asymptomatic women was 80.0%, specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 88.9%. For symptomatic women, the sensitivity of PET was 100%, specificity of 85.7%, a positive predictive value of 93.3%, and a negative predictive value of 100%. CONCLUSIONS: The whole-body FDG PET scan is a sensitive imaging modality for the detection of recurrent cervical carcinoma in both symptomatic and asymptomatic women.