Authorship growth in contemporary medical literature.

OBJECTIVES: The aims of this study were to investigate authorship trends among publications in high-impact, peer-reviewed specialty journals published within the last decade and to assess how publication practices differ among medical specialties. METHODS: The National Institutes of Health's Portfolio Analysis platform, iCite, was queried for PubMed-indexed case reports, review articles, and original research articles published between 2005 and 2017 in 69 high-impact, clinical journals encompassing 23 medical specialties. Overall, 121,397 peer-reviewed publications were evaluated-of which, 45.1% were original research, 28.7% were review articles, and 26.3% were case reports. Multivariable regression was used to evaluate the magnitude of association of publication year on the number of authors per article by specialty and article type. RESULTS: Original research articles have the greatest increase in authorship (0.23 more authors per article per year), as compared with review articles (0.18 authors per article per year) and case reports (0.01 authors per article per year). Twenty-two of the 23 specialties evaluated had increase in authorship in high-impact specialty journals. Specialty growth rates ranged from 0.42 authors/year (Neurology), Psychiatry (0.35 authors/year), General Surgery (0.29 authors/year), Urology (0.27 authors/year), and Pathology (0.27 authors/year). Specialties with a greater percentage of graduates entering academics had more authors per article; surgical specialties and length of residency were not found to be predictive factors. CONCLUSION: There has been substantial growth in the authorship bylines of contemporary medical literature, much of which cannot be explained by increased complexity or collaboration alone.

Financial implications of biparametric prostate MRI.

BACKGROUND: Multiparametric magnetic resonance imaging (MP-MRI) targeted biopsy has been shown to identify more clinically-significant cancers and reduce the detection of clinically-insignificant disease when compared to systematic biopsy; however, the wide-spread accessibility of MP-MRI is limited. A potential strategy for reducing the cost, study time, and contrast-associated risks associated with MP-MRI is elimination of the dynamic contrast-enhanced (DCE) sequence, relying instead on biparametric MRI (BP-MRI). BP-MRI has been shown to have a diagnostic accuracy and cancer detection rate that are equivalent to those of MP-MRI. METHODS: We modeled the potential cost of BP-MRI compared to MP-MRI to determine what cost savings would occur if DCE was eliminated from these studies. RESULTS: When controlled for a 45 min time window that allows for one full MP-MRI or three full BP-MRI studies, the BP-MRI 45 min gross profit is $1531.32. This is an increase in gross profit of $892.58 for the 45 min time window or $10,710.98 in a 9-h business day when performing BP-MRI compared to MP-MRI for prostate cancer detection. CONCLUSIONS: BP-MRI has the potential to result in substantial cost benefit and increased access to MRI in the diagnostic workflow and risk-stratification of men being evaluated for prostate cancer when compared to conventional MP-MRI.

Association Between Tumor Multifocality on Multi-parametric MRI and Detection of Clinically-Significant Prostate Cancer in Lesions with Prostate Imaging Reporting and Data System (PI-RADS) Score 4.

OBJECTIVE: To investigate whether presence of multifocality on multi-parametric magnetic resonance imaging would increase the likelihood of detecting clinically-significant prostate cancer in a PI-RADS 4 lesion. METHODS: We identified patients with at least 1 PI-RADS 4 lesion who underwent multi-parametric magnetic resonance imaging-ultrasound fusion prostate biopsy. Patients were grouped into 1 of 4 cohorts-cohort 1 (a PI-RADS 4 index lesion and an additional PI-RADS 2 or 3 lesion), cohort 2 (single lesion with PI-RADS 4), cohort 3 (2 or more PI-RADS 4 lesions), or cohort 4 (a PI-RADS 4 lesion and an index lesion with PI-RADS 5). We compared the rate of grade group (GG) ≥ 2 pathology on targeted biopsy of PI-RADS 4 lesions between cohorts and evaluated clinical and radiological factors associated with cancer detection. RESULTS: The overall rate of GG ≥ 2 pathology in the PI-RADS 4 lesions was 35.2%. The rate of GG ≥ 2 pathology in the cohorts 1, 2, 3, and 4 was 21.7%, 36.3%, 49.1%, and 42.7%, respectively (P< .001). On multivariable analysis, age (OR1.06, P < .001), clinical stage T2 (OR1.59, P= .03), prostate-specific antigen density (OR1.43, P < .001), peripheral zone lesion (OR1.62, P = .04), and study cohort (cohort 2 vs 1, OR1.93, P = .006; and cohort 3 vs 1, OR3.28, P < .001) were significantly associated with the risk of GG ≥ 2 in the PI-RADS 4 lesion. CONCLUSION: On targeted biopsy of the PI-RADS 4 lesions, the proportion of GG ≥ 2 pathology is approximately 35%. Rate of GG ≥ 2 detection in PI-RADS 4 lesions might differ based on their location, multifocality, and PI-RADS classifications of other lesions identified.

Comparison of biparametric MRI to full multiparametric MRI for detection of clinically significant prostate cancer.

BACKGROUND: Multiparametric magnetic resonance imaging (MP-MRI) and MRI/ultrasound (US) fusion-guided biopsy are becoming more widely used techniques for prostate cancer (PCa) diagnosis and management. However, their widespread adoption and use, where available, are limited by cost and added time. These limitations could be minimized if a biparametric MRI (BP-MRI) focusing on T2-weighted and diffusion-weighted imaging is performed. Herein we report the cancer detection rate of BP-MRI compared with full MP-MRI. METHODS: Biopsy-naive and prior negative biopsy patients with clinical suspicion for PCa underwent MP-MRI with an imaging protocol incorporating narrow field-of-view T2-weighted, diffusion-weighted, and DCE pelvic MRI. Then patients underwent MRI/US fusion-guided biopsy of target lesions between November 2013 and October 2017. The pathology results were compared to the positivity of the DCE sequence compared to the BP-MRI findings alone. RESULTS: There were 648 targeted lesions biopsied in 344 patients. We defined biparametric screen filter positivity as both T2-weighted and diffusion-weighted imaging positivity for the same lesion. The majority of target lesions (552/648, 85%) were screen filter positive. For those that were screen filter negative, a minority (14/96, 15%) had DCE-positive findings. Of these, 2/3 (67%) cancer-positive cases were seen on T2-weighted imaging. For those 82 that were screen filter negative and DCE negative, the DCE phase would not have added imaging suspicion. Only 3/82 (3.7%) were cancer positive; 2 with low risk, grade group 1 cancer and 1 with intraductal carcinoma, all identified on targeted T2-weighted MRI positivity. CONCLUSIONS: BP-MRI for the evaluation of PCa and for guiding MRI/US fusion-targeted biopsy has the advantages of reducing cost, time, and contrast exposure of MP-MRI by eliminating the DCE phase. These benefits are realized without forfeiting valuable diagnostic information, as shown by similar cancer detection rates of BP-MRI and MP-MRI in this study, particularly for clinically significant cases of PCa.

Incidental findings on multiparametric MRI performed for evaluation of prostate cancer.

PURPOSE: Multiparametric magnetic resonance imaging (mp-MRI) and MRI/Ultrasound (US) fusion-guided biopsy are relatively new techniques for improved detection, staging, and active surveillance of prostate cancer (PCa). As with all imaging modalities, MRI reveals incidental findings (IFs) which carry the risk of increased cost, patient anxiety, and iatrogenic morbidity due to workup of IFs. Herein, we report the IFs from 684 MRIs for evaluation of PCa and consider their characteristics and clinical significance. METHODS: Patients underwent mp-MRI prostate protocol incorporating triplanar T2-weighted, diffusion-weighted, and dynamic contrast-enhanced pelvic MRI as well as a post-contrast abdominopelvic MRI with the primary indication of detection or evaluation of PCa. A total of 684 consecutive prostate MRI reports performed in a series of 580 patients were reviewed. All extraprostatic findings reported were logged and then categorized by organ system and potential clinical significance. RESULTS: There were 349 true IFs found in 233 (40%) of the 580 patients. One hundred nineteen additional extraprostatic findings were unsuspected but directly related to PCa staging, while the 349 IFs were unrelated and thus truly incidental beyond study indication. While the majority of true IFs were non-urologic, only 6.6% of IFs were considered clinically significant, non-urologic findings, and more than a third of MRI reports had urologic IFs not related to PCa. CONCLUSIONS: Rates of incidental findings on prostate indication MRI are similar to other abdominopelvic imaging studies. However, only 6.6% of the IFs were considered to be clinically significant non-urologic findings. Further investigations are needed to assess downstream workup of these IFs and resulting costs.