Cancers of Unknown Primary: A Descriptive Study in the U.S. Military Health System

Predicting survival of patients with bone metastasis of unknown origin

Purpose

Bone metastasis of unknown origin is a rare and challenging situation, which is infrequently reported. Therefore, the current study was performed to analyze the clinicopathologic features and risk factors of survival among patients with bone metastasis of unknown origin.

Patients and methods

We retrospectively analyzed the clinical data for patients with bone metastasis of unknown origin between 2010 and 2016 based on the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) were first analyzed by applying univariable Cox regression analysis. Then, we performed multivariable analysis to confirm independent survival predictors.

Results

In total, we identified 1224 patients with bone metastasis of unknown origin for survival analysis, of which 704 males (57.5%) and 520 females (42.5%). Patients with bone metastasis of unknown origin had a 1-year OS rate of 14.50% and CSS rate of 15.90%, respectively. Race, brain metastasis, liver metastasis, radiotherapy, and chemotherapy were significant risk factors of OS on both univariable and multivariable analyses (p <0.05). As for CSS, both univariable and multivariable analyses revealed that no brain metastasis, no liver metastasis, radiotherapy, and chemotherapy were associated with increased survival (p <0.05).

Conclusion

Patients with bone metastasis of unknown origin experienced an extremely poor prognosis. Radiotherapy and chemotherapy were beneficial for prolonging the survival of those patients.

Integrating Medical Genetics Into Precision Oncology Practice in the Veterans Health Administration: The Time Is Now

PURPOSE

Increased access and utilization of tumor profiling of cancers in our veteran population uncovered a modest number of potentially pathogenic germline variants (PPGVs) that require genetics referral for follow-up evaluation and germline sequencing. Challenges identified specific to the veteran population include paucity of genetics providers, either at a veteran's VA facility or nearby non-VA facilities. We sought to investigate the number of veterans who would benefit from having such resources at both local and national levels.

METHODS

Annotated clinical reports of mutations identified by tumor-only profiling and medical records of veterans with solid tumors at the Veterans Administration Ann Arbor Healthcare System (VA AAHS) between 2015 and 2020 were reviewed. PPGVs were identified according to society recommendations (such as ESMO and American Board of Medical Genetics and Genomics), expert review, and/or previously published criteria. After the analysis of our local VA population, these same criteria were then applied to veterans in the National Precision Oncology Program (NPOP).

RESULTS

Two hundred eight veterans underwent tumor profiling at the VA AAHS over the defined time period. This included 20 different primary tumor sites with over half (n = 130) being advanced cancer at diagnosis. Of these, 18 veterans (8.5%) had mutations suggestive of a PPGV. Applying these criteria to the larger NPOP database (n = 20,014), a similar percentage (6%) of PPGVs were identified.

CONCLUSION

These results indicate a PPGV frequency (6%-9% of veterans) consistent with the prevalence of inherited cancer predisposition syndromes in the general population, underscoring the need for medical genetics as part of standard oncologic care for veterans. We explore current and future care delivery models to optimize incorporation of medical genetics and genetic counseling to best serve veterans needing such services.