Why Research on Diagnosis Is Critical to Progress against Cancer
Advances in the diagnosis of cancer have the potential to improve outcomes for many patients with the disease. Doctors and patients depend on accurate information derived from diagnostic tools, such as clinical laboratory tests, imaging studies, and genomic analysis, to make decisions at all stages of cancer care. Diagnostic tools can
- help determine the impending risk of cancer
- help determine the extent of cancer within the body (staging)
- classify groups of patients with tumors that share certain genetic changes
- inform decisions about treatment, such as identifying the treatment that is most likely to be effective for a given patient
- assess a patient’s response to treatment
- monitor a patient for a recurrence of cancer
Opportunities in Cancer Diagnosis Research
Cancer diagnosis has long relied on the microscopic examination of cells to see if they have the appearance of cancer cells. Diagnosis often includes the use of molecular and cytogenetic markers to collect additional information about the tumor. The development of new technologies for analyzing DNA and other molecules in tumors has created opportunities to develop additional biomarkers for cancer diagnosis.
Recognizing this opportunity, as well as the challenges involved in developing new tools and methods, researchers at NCI and elsewhere developed a checklist of criteria that can be used to determine the readiness of new omics-based tests for guiding patient care in clinical trials.
Omics tests include those based on such disciplines as genomics, epigenomics, transcriptomics, proteomics, and metabolomics, which is the study of small-molecule metabolites in cells and tissues that are present in bodily fluids, such as blood and urine.
Advances in technology have also created opportunities to develop and test new imaging methods in cancer diagnosis. For instance, a study by NCI researchers showed that an image-guided biopsy for the detection of prostate cancer did a better job of identifying men with high-risk disease than standard biopsy, while also reducing the detection of low-risk disease that may not need treatment.
Other opportunities in imaging include the development of better tools for imaging tumors and for reading and interpreting scans.
Diagnostic tools that identify specific molecular abnormalities in tumors are also important in the context of precision medicine. With this information, doctors can determine whether a patient has the target for a particular targeted therapy or does not and should avoid taking the drug. In recent years, the Food and Drug Administration (FDA) has approved tests called companion diagnostics to help identify candidates for certain treatments. Patients may be required to undergo one of these tests prior to starting treatment with a targeted therapy.
Challenges in Cancer Diagnosis Research
To be useful in the clinic, diagnostic test results must be reliable and should be returned to patients and doctors within a relatively short time frame.
Establishing the predictive value of diagnostic tools is a challenge, particularly given the heterogeneity of cancers and variation in clinical courses, even for patients with the same type of cancer. In a diagnostic setting, the sensitivity of a test is important. For example, although many potential omics-based tests have shown promise in preclinical studies, few have been translated into clinically useful tests due to poor sensitivity.
More than 20 tumor markers are currently in use, but there are some limitations to the use of these diagnostic tools. Not everyone with a particular type of cancer will have a higher level of a tumor marker associated with that cancer, for example. Moreover, tumor markers have not been identified for every type of cancer. For more information on tumor markers, see the Tumor Markers fact sheet.
Another research challenge is to develop ways to monitor, in real time, molecular changes within tumors over the course of treatment and beyond, particularly for tumors that are poorly accessible.
There is also a need to give patients information about the likelihood that a given tumor will be life-threatening. Indeed, as the technology for identifying tumors has improved, the number of over-diagnosed cancers that are not likely to cause harm or death has risen. Therefore, there is an even greater need for tools to accurately assess the risks these tumors pose to patients.
NCI’s Role in Cancer Diagnosis Research
NCI supports research on novel tools and methods for diagnosing cancer. This work includes the development of tests and imaging technologies that can provide specific information about an individual’s cancer. Other priorities include the development of diagnostic tools that can be used in laboratory research.
One of eight major programs managed by NCI’s Division of Cancer Treatment and Diagnosis (DCTD), the CDP aims to improve the diagnosis and assessment of cancer. Investigators supported by CDP work on a range of projects, including the development of diagnostic tests to better characterize cancers and provide information that can help doctors and patients make clinical decisions. The program supports research at medical centers, hospitals, businesses, and universities throughout the United States. Two CDP initiatives are the:
- Program for the Assessment of Clinical Cancer Tests (PACCT), which focuses, in part, on barriers that affect the development of improved tests for cancer diagnosis. PACCT helped facilitate a workshop on criteria for the use of “omics”-based predictors (such as genomic and proteomic test results) in NCI-supported clinical trials.
PACCT also played a role in developing the TAILORx clinical trial. This NCI-sponsored study is using a gene-based test to see if a panel of genes that are frequently associated with risk of recurrence in women with early-stage breast cancer can be used to assign patients to the most appropriate and effective treatment. Specifically, the test helps to assess the likely benefit from certain types of chemotherapy.
- Strategic Partnering to Evaluate Cancer Signatures (SPECS) program, which supports research groups that are exploring how information from molecular analyses can affect the care of patients and ultimately improve outcomes. The SPECSII program includes researchers who are studying lung, colon, and prostate cancers; acute leukemia; and non-Hodgkin lymphoma.
DCTD’s CIP supports research on the use of imaging techniques to noninvasively diagnose cancer and the identification of disease subsets in patients, among other research areas. An area of focus for CIP researchers is functional or molecular imaging, which visualizes physiological, cellular, or molecular processes in living tissues as they occur. Molecular imaging is critical for fundamental improvements in the care of patients with cancer.CIP supports the:
- In Vivo Cellular and Molecular Imaging Centers (ICMIC), where scientists from a variety of fields conduct multidisciplinary research on cellular and molecular imaging related to cancer. Pre-ICMIC planning grants provide time and funds for investigators and institutions to prepare themselves, organizationally and scientifically, to establish ICMICs.
EDRN, managed by NCI’s Division of Cancer Prevention (DCP), focuses on the development and testing of promising biomarkers or technologies to improve risk assessment and the early detection of cancer. A goal of the EDRN is to make molecular diagnostics a reality. EDRN is a consortium of more than 300 investigators who represent diverse scientific disciplines, including genomics, informatics, and public health.
Molecular and Cellular Screening of Screen-Detected Lesions (MCSSL) Initiative
MCSSL aims to reduce the number of over-diagnosed tumors by studying the biology of indolent tumors, those lesions that tend to grow slowly, to understand their progression from benign to invasive cancer. This program is managed jointly by DCP and NCI’s Division of Cancer Biology.
NCI's Intramural Cancer Diagnosis Research
- CCR researchers in the Center for Advanced Preclinical Research (CAPR) have expertise in preclinical imaging studies and biomarker development.
- CCR’s Clinical Molecular Profiling Core uses genomic technologies to analyze biospecimens obtained from NCI clinical trials.
- NCI’s Center of Excellence in Integrative Cancer Biology and Genomics (CEICBG), which is sponsored by CCR and DCEG, promotes research efforts to identify, develop, and validate biomarkers for the early detection and diagnosis of cancer, among many other activities.