Impact of mesorectal extranodal tumor deposits in magnetic resonance imaging on outcome of rectal cancer patients.

AIM: Mesorectal extranodal tumor deposits (TDs) are identified in many rectal cancers. Their radiological features differ from metastatic lymph nodes, and they can be detected with magnetic resonance imaging (MRI). The purpose of this study was to determine the prevalence of rectal cancer TDs detected with MRI and their impact on overall (OS), cancer-specific (CSS), and disease-free survival (DFS) and the local recurrence rate. METHOD: In this retrospective cohort study, we screened all 525 consecutive rectal cancer patients who underwent surgery during 2017-2018 in a tertiary center. Patients with synchronous metastases or who had not undergone MRI were excluded. We analyzed the OS, CSS, and DFS as well as local recurrences. RESULTS: Of the 480 included patients, TDs were detected in the images of 81 (16.9 %). Extramural venous invasion (EMVI) and TDs were frequently found together (n = 50, 61.7 % of all cases with TDs). The presence of TDs alone [hazard ratio (HR) 1.66 (1.03-2.68)] or TDs and/or EMVI [HR 1.63 (1.01-2.62)] were risk factors for adverse DFS in multivariate Cox regression analysis. The OS and CSS rates were poorer among patients with TDs compared to those without, p = 0.009 and p < 0.001, respectively. TDs were also a risk factor for local recurrence in the univariate analysis. CONCLUSIONS: TDs detected with imaging are a risk factor for impaired DFS and associated with impaired CSS and OS of rectal cancer patients and should be taken into consideration in clinical decision-making.

Findings in magnetic resonance imaging for restaging locally advanced rectal cancer.

PURPOSE: We aimed to assess the prognostic value of restaging magnetic resonance imaging (MRI) in rectal cancer after neoadjuvant therapy and compare long-course chemoradiotherapy (LC-CRT) to short-course radiotherapy with delayed surgery (SCRT-delay). METHODS: This retrospective study included 267 patients with locally advanced rectal cancer (LARC) operated on between January 2016 and April 2019, all of whom received either LC-CRT or SCRT-delay in the neoadjuvant setting. The primary outcomes were overall survival (OS) and cancer-specific survival (CSS) based on radiological response assessed using the magnetic resonance tumor regression grade (mrTRG). RESULTS: In the LC-CRT group, cumulative 1-, 3-, and 5-year OS rates were 94.8%, 86.4%, and 79.0%, while in the SCRT-delay group, they were 83.3%, 68.9%, and 68.9% (P = 0.017). For CSS in the LC-CRT group, cumulative rates were 96.9%, 90.3%, and 85.0%, and in the SCRT-delay group, they were 88.6%, 81.4%, and 81.4% (P = 0.222). There were no significant differences in total histological response rates or local recurrence rates between the treatment groups. The good and moderate response group (mrTRG 1-3) had significantly better cumulative 1-, 3-, and 5-year OS and CSS compared to the poorer response group (mrTRG 4-5) (P = 0.023 for OS and P = 0.048 for CSS). CONCLUSION: Unfavorable MRI response is a sign of poor prognosis in LARC. SCRT-delay is comparable to LC-CRT concerning the oncological outcome.

Expected impact of MRI-related interreader variability on ProScreen prostate cancer screening trial: a pre-trial validation study.

BACKGROUND: The aim of this study is to investigate the potential impact of prostate magnetic resonance imaging (MRI) -related interreader variability on a population-based randomized prostate cancer screening trial (ProScreen). METHODS: From January 2014 to January 2018, 100 men aged 50-63 years with clinical suspicion of prostate cancer (PCa) in Helsinki University Hospital underwent MRI. Nine radiologists individually reviewed the pseudonymized MRI scans of all 100 men in two ProScreen trial centers. All 100 men were biopsied according to a histological composite variable comprising radical prostatectomy histology (N = 38) or biopsy result within 1 year from the imaging (N = 62). Fleiss' kappa (κ) was used to estimate the combined agreement between all individual radiologists. Sample data were subsequently extrapolated to 1000-men subgroups of the ProScreen cohort. RESULTS: Altogether 89% men of the 100-men sample were diagnosed with PCa within a median of 2.4 years of follow-up. Clinically significant PCa (csPCa) was identified in 76% men. For all PCa, mean sensitivity was 79% (SD ±10%, range 62-96%), and mean specificity 60% (SD ±22%, range 27-82%). For csPCa (Gleason Grade 2-5) MRI was equally sensitive (mean 82%, SD ±9%, range 67-97%) but less specific (mean 47%, SD ±20%, range 21-75%). Interreader agreement for any lesion was fair (κ 0.40) and for PI-RADS 4-5 lesions it was moderate (κ 0.60). Upon extrapolating these data, the average sensitivity and specificity to a screening positive subgroup of 1000 men from ProScreen with a 30% prevalence of csPCa, 639 would be biopsied. Of these, 244 men would be true positive, and 395 false positive. Moreover, 361 men would not be referred to biopsy and among these, 56 csPCas would be missed. The variation among the radiologists was broad as the least sensitive radiologist would have twice as many men biopsied and almost three times more men would undergo unnecessary biopsies. Although the most sensitive radiologist would miss only 2.6% of csPCa (false negatives), the least sensitive radiologist would miss every third. CONCLUSIONS: Interreader agreement was fair to moderate. The role of MRI in the ongoing ProScreen trial is crucial and has a substantial impact on the screening process.

Prostate MRI added to CAPRA, MSKCC and Partin cancer nomograms significantly enhances the prediction of adverse findings and biochemical recurrence after radical prostatectomy.

BACKGROUND: To determine the added value of preoperative prostate multiparametric MRI (mpMRI) supplementary to clinical variables and their role in predicting post prostatectomy adverse findings and biochemically recurrent cancer (BCR). METHODS: All consecutive patients treated at HUS Helsinki University Hospital with robot assisted radical prostatectomy (RALP) between 2014 and 2015 were included in the analysis. The mpMRI data, clinical variables, histopathological characteristics, and follow-up information were collected. Study end-points were adverse RALP findings: extraprostatic extension, seminal vesicle invasion, lymph node involvement, and BCR. The Memorial Sloan Kettering Cancer Center (MSKCC) nomogram, Cancer of the Prostate Risk Assessment (CAPRA) score and the Partin score were combined with any adverse findings at mpMRI. Predictive accuracy for adverse RALP findings by the regression models was estimated before and after the addition of MRI results. Logistic regression, area under curve (AUC), decision curve analyses, Kaplan-Meier survival curves and Cox proportional hazard models were used. RESULTS: Preoperative mpMRI data from 387 patients were available for analysis. Clinical variables alone, MSKCC nomogram or Partin tables were outperformed by models with mpMRI for the prediction of any adverse finding at RP. AUC for clinical parameters versus clinical parameters and mpMRI variables were 0.77 versus 0.82 for any adverse finding. For MSKCC nomogram versus MSKCC nomogram and mpMRI variables the AUCs were 0.71 and 0.78 for any adverse finding. For Partin tables versus Partin tables and mpMRI variables the AUCs were 0.62 and 0.73 for any adverse finding. In survival analysis, mpMRI-projected adverse RP findings stratify CAPRA and MSKCC high-risk patients into groups with distinct probability for BCR. CONCLUSIONS: Preoperative mpMRI improves the predictive value of commonly used clinical variables for pathological stage at RP and time to BCR. mpMRI is available for risk stratification prebiopsy, and should be considered as additional source of information to the standard predictive nomograms.

F-18-fluorodeoxyglucose positron emission tomography-guided sampling of mediastinal lymph nodes in the diagnosis of cardiac sarcoidosis.

Histologic proof of granulomatous inflammation is prerequisite for the diagnosis of cardiac sarcoidosis (CS). Because of the limited sensitivity of endomyocardial biopsy (EMB), confirmation of sarcoidosis often has to be acquired from extracardiac biopsies. We set out to review our experience of F-18-fluorodeoxyglucose positron emission tomography (F-18-FDG PET) in guiding extracardiac tissue biopsies in suspected CS. We included in this work 68 consecutive patients with proved CS who had undergone cardiac F-18-FDG PET with (n = 57) or without whole-body imaging as part of initial diagnostic evaluation. Their hospital charts, imaging studies, and diagnostic biopsies were reviewed in retrospect. Whole-body PET images showed extracardiac foci of abnormally high F-18-FDG uptake in 39 of 57 patients, of whom 38 had involvement of mediastinal lymph nodes (MLN). Parallel F-18-FDG uptake was found in other lymph nodes (n = 10), lungs (n = 9), liver (n = 3), spleen (n = 2), and thyroid gland (n = 1). Adding the mediastinal findings at cardiac PET without whole-body imaging, abnormal F-18-FDG uptake in MLN was found in totally 43 of the 68 patients with CS (63%). Histology of systemic sarcoidosis was known at presentation of cardiac symptoms in 8 patients. Of the 60 patients with missing histology, 24 patients underwent mediastinoscopy for sampling of PET-positive MLN, most often (n = 20) after nondiagnostic EMB; microscopy revealed diagnostic noncaseating granulomatous inflammation in 24 of the 24 cases (sensitivity 100%). In the remaining 36 patients, sarcoidosis histology was confirmed by EMB (n = 30), by biopsy of lungs (n = 2) or peripheral lymph nodes (n = 2), or at autopsy (n = 1) or post-transplantation (n = 1). In conclusion, MLN accumulate F-18-FDG at PET in most patients with CS and provide a highly productive source for diagnostic biopsies either primarily or subsequent to nondiagnostic EMB.