Cancer molecular imaging is the noninvasive visualization of a process unique to or altered in neoplasia, such as proliferation, glucose metabolism, and receptor expression, which is relevant to patient management. Several molecular imaging modalities are now available, including magnetic resonance, optical, and nuclear imaging. Nuclear imaging, particularly using fluorine-18-fluorodeoxyglucose positron emission tomography, is widely used in the staging and response assessment of multiple cancer types. However, at this writing, new nuclear medicine probes, especially positron emission tomography tracers, are increasingly used or are being investigated for cancer evaluation. This review focuses on these probes, their biologic targets, and the applications or potential applications for their use in the assessment of various neoplasms, including both probes available for commercial use-such as somatostatin receptor ligands in neuroendocrine tumors, prostate-specific membrane antigen ligands in prostate cancer, norepinephrine analogs in neural crest tumors like neuroblastoma, and estrogen analogs in breast cancer-and others in clinical development, such as fibroblast-activating protein inhibitors, C-X-C chemokine receptor type 4 ligands, and monoclonal antibodies targeting receptor tyrosine kinases, CD4-positive or CD8-positive tumor-infiltrating lymphocytes, tumor-associated macrophages, and cancer stem cell biomarkers. These developments represent a major step toward the integration of molecular imaging as a powerful tool in precision medicine, with an expectedly significant impact on patient management and outcome.
When Patricia Santos, MD, was a medical resident in radiation oncology at Memorial Sloan Kettering Cancer Center (MSKCC) in New York, she and her colleagues observed the numerous challenges that people experiencing homelessness (PEH) face after a cancer diagnosis.
“A number of us who were doing work in this space had our own individual stories of what we saw on a one-on-one basis, but we found very little literature on what that actually meant for cancer care delivery and services among the unhoused,” says Dr Santos, now an assistant professor of radiation oncology at Emory University School of Medicine in Atlanta, Georgia.
She practices at Atlanta’s Grady Memorial Hospital, one of the largest public safety net hospitals in the country.
Setting out to learn more while still at MSKCC, she and her colleagues launched a study that was published in JAMA Oncology (doi:10.1001/jamaoncol.2024.3645). This large cross-sectional study of hospitalized US adults diagnosed with cancer found that PEH had higher prevalences of lung and upper gastrointestinal cancers along with comorbid substance use disorder and HIV. Despite these diagnoses and longer hospital stays, these individuals were less likely to undergo invasive procedures or systemic therapy or have higher-than-median costs of stay than housed populations. Homelessness was associated with a lower rate of death while a patient was in the hospital. However, PEH were found to be 4 times more likely to be discharged against medical advice.
Using the 2016–2020 National Inpatient Sample, the cross-sectional study assessed hospitalized inpatient adults aged 18 years or older who were diagnosed with cancer. Researchers developed a cohort of PEH and housed individuals who were matched according to age, sex, race, ethnicity, insurance type, cancer diagnosis, number of comorbidities, substance abuse disorder, severity of illness, year of admission, hospital location, hospital ownership, region, and hospital bed size.
The study included 13,793,462 housed individuals (median age, 68 years) and 45,150 PEH (median age, 58 years).