Anorectal function and radiation dose to pelvic floor muscles after primary treatment for anal cancer

BACKGROUND AND PURPOSE

Chemoradiotherapy is the primary treatment for localized anal cancer (AC). This treatment offers high rates of cure and organ preservation. Radiotherapy can however, result in late persisting anorectal dysfunction, with anal incontinence, urge and clustering. Correlation of radiation doses to pelvic substructures and functional outcome is not well described in AC. We correlated patient reported anorectal function to radiation doses to sphincters and pelvic floor muscles.

MATERIALS AND METHODS

Patients treated with (chemo)radiotherapy for AC were asked to fill out LARS (lower anterior resection syndrome) questionnaires at follow-up. We compared patients with no LARS (score 0-19) and patients with major LARS (30-42) as well as individual LARS questions to specific radiation doses to sphincters, levators and puborectal muscles.

RESULTS

Thirty-six patients were included, 18 with no LARS and 18 with major LARS. Gender, age, TNM stage, PTV, chemotherapy, time to LARS score (mean 660 and 749 days) were comparable between the two groups. LARS symptoms, occurring at least once per week, were reported between 25-55.7%, and poorer LARS outcome was associated to worse quality of life. Dose to sphincter complex (Dmean, V50Gy and D90%) differed significantly between patients with no and major LARS (p = 0.048, 0.035 and 0.02 respectively). Further, D90% to the sphincter complex was significantly higher in patients who had accidental leakage of stool, (p = 0.044).

CONCLUSION

Patients treated with (chemo)radiotherapy for AC show high frequency of patient reported anorectal dysfunction. Specific doses to the sphincters could become a useful predictor of anal incontinence and major LARS and incorporated into future radiotherapy planning studies.

Impact of a multidisciplinary training programme on outcome of upper rectal cancer by critical appraisal of the extent of mesorectal excision with postoperative MRI

BACKGROUND

Optimal management of patients with upper rectal cancer remains unclear. Partial mesorectal excision (PME) without neoadjuvant therapy is currently advocated for the majority of patients. Recent studies, however, reported a high risk of local recurrence and suboptimal surgery. The aim of this study was to evaluate the effects of a quality assurance initiative with postoperative MRI to improve outcomes in these patients.

METHODS

Patients who underwent mesorectal excision with curative intent for rectal cancer in 2007-2013 were included. Postoperative MRI of the pelvis was performed 1 year after surgery. In 2011, a multidisciplinary workshop with focus on extent and completeness of surgery was held for training surgeons, pathologists and radiologists involved in treatment planning. Images of residual mesorectum and histopathological reports were reviewed with regard to the distal resection margin. Local recurrence after a minimum of 3 years' follow-up was compared between two cohorts from 2007-2010 and 2011-2013.

RESULTS

A total of 627 patients were included; postoperative MRI of the pelvis was done in 381 patients. The 3-year actuarial local recurrence rate in patients with upper rectal cancer improved from 12·9 to 5·0 per cent (P = 0·012). After the workshop, fewer patients with cancer of the upper rectum were selected to have PME (90·8 per cent in 2007-2010 versus 80·2 per cent in 2011-2013; P = 0·023), and fewer patients who underwent PME had an insufficient distal resection margin (61·7 versus 31 per cent respectively; P < 0·001).

CONCLUSION

Quality assessment of surgical practice may have a major impact on oncological outcome after surgery for upper rectal cancer.

Independent Validation of a Diagnostic Noninvasive 3-MicroRNA Ratio Model (uCaP) for Prostate Cancer in Cell-Free Urine

BACKGROUND

Detection of prostate cancer (PC) based on serum prostate-specific antigen (PSA) testing leads to many unnecessary prostate biopsies, overdiagnosis, and overtreatment of clinically insignificant tumors. Thus, novel and more accurate molecular biomarkers are required.

METHODS

Using reverse transcription quantitative PCR, we measured the concentrations of 45 preselected microRNAs (miRNAs) in extracellular vesicle-enriched cell-free urine samples from 4 independent patient cohorts from Spain and Denmark, including 758 patients with clinically localized PC, 289 noncancer controls with benign prostatic hyperplasia (BPH), and 233 patients undergoing initial transrectal ultrasound (TRUS)-guided prostate biopsy owing to PC suspicion (101 with benign and 132 with malignant outcome). Diagnostic potential was assessed by ROC and decision curve analysis.

RESULTS

We identified and successfully validated 8 upregulated and 21 downregulated miRNAs in urine from PC patients. Furthermore, we validated a previously identified 3-miRNA diagnostic ratio model, uCaP (miR-222-3p*miR-24-3p/miR-30c-5p). High uCaP scores were distinctive of PC in urine samples from BPH vs PC patients in 3 independent cohorts [area under the curve (AUC) = 0.84, 0.71, 0.72]. Additionally, uCaP predicted TRUS biopsy results with greater accuracy than PSA (AUC uCaP = 0.644; AUC PSA = 0.527) for patients within the diagnostic gray zone (PSA ≤ 10 ng/mL).

CONCLUSIONS

We successfully validated a urine-based diagnostic 3-miRNA signature for PC (uCaP) in 3 independent patient cohorts from 2 countries. In the future, the simple and noninvasive uCaP test may be used to help more accurately select patients for prostate biopsy. Prospective clinical validation is warranted.

Quantitative Tumor Perfusion Imaging with 82Rb PET/CT in Prostate Cancer: Analytic and Clinical Validation

The aim of this work was to evaluate ⁸²Rb PET/CT as a diagnostic tool for quantitative tumor blood flow (TBF) imaging in prostate cancer (PCa). Study 1 was performed to evaluate ⁸²Rb as a marker of TBF, using ¹⁵O-H₂O PET as a reference method. Study 2 investigated the ability of ⁸²Rb uptake measurements to differentiate between PCa and normal prostate. Methods: Study 1: 9 PCa patients scheduled for radical prostatectomy were included. Prostate multiparametric MRI and both cardiac and pelvic ¹⁵O-H₂O PET and ⁸²Rb PET were performed. PET findings were compared with postprostatectomy Gleason grade group (GGG). Study 2: 15 primary high-risk PCa patients and 12 controls without known prostate disease were included in a clinical drug trial (EudraCT 2016-003185-26). ⁶⁸Ga-prostate-specific membrane antigen PET/CT scans of PCa patients were available. Pelvic ⁸²Rb PET was performed. Results: Study 1: both ⁸²Rb K ₁ and ⁸²Rb SUVs correlated strongly with ¹⁵O-H₂O TBF (ρ = 0.95, P < 0.001, and ρ = 0.77, P = 0.015, respectively). ⁸²Rb SUV and K ₁ were linearly correlated (r = 0.92, P = 0.001). ⁸²Rb SUV correlated with postprostatectomy GGG (ρ = 0.70, P = 0.03). Study 2: ⁸²Rb SUV in PCa (3.19 ± 0.48) was significantly higher than prostate ⁸²Rb SUV in healthy controls (1.68 ± 0.37) (P < 0.001), with no overlap between groups. Conclusion: Study 1 shows that ⁸²Rb PET/CT can be used for TBF quantification and that TBF can be estimated by simple SUV and suggests that ⁸²Rb SUV is associated with postprostatectomy GGG and, hence, cancer aggressiveness. Study 2 shows that ⁸²Rb uptake is significantly higher in PCa than in normal prostate tissue with no overlap between cohorts, confirming the primary hypothesis of the clinical trial. Consequently, ⁸²Rb PET/CT may have potential as a noninvasive tool for evaluation of tumor aggressiveness and monitoring in nonmetastatic PCa.

Hypercortisolism in Newly Diagnosed Type 2 Diabetes: A Prospective Study of 384 Newly Diagnosed Patients

Cross-sectional studies in small and selected populations report a high prevalence of hypercortisolism in patients with type 2 diabetes (T2D), which could have therapeutic implications, if confirmed. We therefore estimated the prevalence of hypercortisolism in a large and unselected cohort of recently diagnosed T2D patients. Consecutive patients with recently diagnosed T2D first underwent an overnight dexamethasone (1 mg) suppression test (OD). Patients not suppressing serum cortisol ≤50 nmol/l proceeded with a 48-h low dose dexamethasone suppression test (LDDST) and 24-h urinary free cortisol collection (UFC). Patients with elevated cortisol levels according to LDDST and/or UFC underwent imaging guided by plasma ACTH levels, and assessment of bone mineral density. A total of 384 T2D patients (232male/152 females) with a mean age of 60±10 years were included. Eighty-five (22%) patients suppressed incompletely to OD of whom 20 (5%) failed to suppress after LDDST and/or had elevated UFC (=hypercortisolism). Patients with hypercortisolism did not differ as regards age, BMI, HbA1c, T-score or blood pressure, but a higher proportion of them received antihypertensive treatment (100% vs. 64%, p=0.001). Imaging revealed adrenal adenoma(s) in 9 cases and a pituitary macroadenoma in 1 case. We found a 5% prevalence of hypercortisolism in unselected, recently diagnosed T2D, which was not associated with a persuasive cushingoid phenotype. The clinical implications are therefore uncertain.

Non-invasive quantification of tumor blood flow in prostate cancer using 15O-H2O PET/CT

Tumor blood flow (TBF) measurements in prostate cancer (PCa) provide an integrative index of tumor growth, which could be important for primary diagnosis and therapy response evaluation. ¹⁵O-water PET is the non-invasive gold standard but is technically demanding. The aim of this study was to compare the accuracy of three different non-invasive strategies with an invasively measured arterial input function (BSIF): Using image-derived input functions (IDIF) from either 1) a separate heart scan or 2) the pelvic scan or 3) a populations-based input function (PBIF). Nine patients with biopsy-verified PCa scheduled for prostatectomy were included. All patients were characterized with serum levels of PSA (s-PSA), multiparametric magnetic resonance imaging (mpMRI) and post-surgical histopathology Gleason Grade. Dynamic ¹⁵O-water was performed of the heart and the pelvic area 15 minutes apart. TBF estimated from both wash-in (K₁) and wash-out (k₂) constants was calculated using a one-compartmental model. Results: Mean (range) s-PSA was 12 (3-27) ng/mL, Gleason Grade Group was 2.9 (1-5), k₂ was 0.44 (0.007-1.2), and K₁ was 0.24 (0.07-0.55) mL/mL/min. k₂ (BSIF) correlated with s-PSA (r=0.86, P<0.01) and Gleason Grade Group (rho=0.78, P=0.01). BSIF, heart-IDIF and PBIF provided near-identical k₂ and K₁ (r>0.95, P<0.001) with slopes near unity. The correlations of BSIF and pelvic-IDIF rate constants were good (r>0.95, P<0.001), but individual errors high. In conclusion, non-invasive protocols for ¹⁵O-water PET with IDIF or PBIF accurately measures perfusion in prostate cancer and might be useful for evaluation of tumor aggressiveness and treatment response.

Pelvic insufficiency fractures frequently occur following preoperative chemo-radiotherapy for rectal cancer - a nationwide MRI study

AIM

The aim of this prospective case-control study was to evaluate the rate of pelvic insufficiency fractures (PIFs) in Denmark using MRI at the 3-year follow-up. All patients had rectal cancer and had undergone surgery with or without preoperative chemo-radiotherapy (CRT).

METHOD

Patients registered with primary rectal cancer in the Danish Colorectal Cancer Group database, who underwent rectal cancer resection from April 2011 through August 2012, were invited to participate in a national MRI study aiming to detect local recurrence and evaluate quality of the surgical treatment. Pelvic MRI including bone-specific sequences 3 years after treatment was obtained. The primary outcome was the rate of PIFs; secondary outcome was risk factors of PIFs evaluated in multivariate analysis.

RESULTS

During the study period, 890 patients underwent rectal cancer surgery. Of these, 403 patients were included in the MRI study and had a 3-year follow-up MRI. PIFs were detected in 49 (12.2%; 95% CI 9.0-15.4) patients by MRI. PIFs were detected in 39 patients (33.6%; 95% CI 24.9-42.3) treated with preoperative CRT compared to 10 (3.5%; 95% CI 1.3-5.6) non-irradiated patients (P < 0.001). In a multivariate analysis female gender (OR = 3.52; 95% CI 1.7-7.5), age above 65 years (OR = 3.20; 95% CI 1.5-6.9) and preoperative CRT (OR = 14.20; 95% CI 6.1-33.1) were significant risk factors for PIFs.

CONCLUSION

Preoperative CRT in the treatment of rectal cancer was associated with a 14-fold higher risk of PIFs after 3 years, whereas female gender and age above 65 years each tripled the risk of PIFs.

Preoperative planning of renal transplantation: a comparison of non-contrast-enhanced ultrasonography, computed tomography, and magnetic resonance angiography with observations from surgery

BACKGROUND

Many candidates for kidney transplantation need to undergo vessel examination before the transplantation procedure.

PURPOSE

To identify the optimal preoperative modality for the examination of vessel status without the use of contrast agents in kidney transplant candidates.

MATERIAL AND METHODS

Fifty-three consecutive patients were examined and 31 patients were transplanted. Ultrasonography (US), non-contrast-enhanced computed tomography (NCCT), and non-contrast-enhanced magnetic resonance angiography (NCMRA) were compared using inspection during kidney transplantation (TX) as a reference standard. The sensitivity and specificity to severe arteriosclerotic changes and the accuracy were calculated. Kappa statistics were used to assess the agreement between TX and the different examination modalities, and McNemar's test was used to test for significant differences.

RESULTS

US had higher sensitivity (1.0) and better agreement with observations from surgery (k = 0.89) than both NCCT (sensitivity = 0.60; k = 0.72) and NCMRA (sensitivity = 0.20; k = 0.30). No significant difference was found between TX and US (P = 0.3173) or TX and NCCT (P = 0.1573), but there was a significant difference between TX and NCMRA (P = 0.0455). US was inconclusive in 20% of cases, and the internal iliac artery could not be visualized in 69% of cases.

CONCLUSION

Either US or NCCT can be used as the preferred preoperative imaging modality to examine vessel status before kidney transplantation, but a combination of the two is preferable. NCMRA should not be used as the sole imaging modality for preoperative imaging before kidney transplantation because of its low sensitivity in detecting severe arteriosclerotic disease without the presence of stenosis.

Neoadjuvant therapy abolishes the functional benefits of a larger rectal remnant, as measured by magnetic resonance imaging after restorative rectal cancer surgery

BACKGROUND

The combination of advances in surgical technique and neoadjuvant therapy for rectal cancer has resulted in more patients undergoing sphincter-preserving surgery. Unfortunately, numerous patients subsequently experience bowel dysfunction, and may suffer from lifelong severe disability with major impact on their quality of life. The aim of the present study was to investigate whether the risk of severe LARS in patients was associated with the length of remnant rectum.

METHODS

A total of 125 patients who underwent sphincter-preserving surgery for rectal cancer were included. Postoperative bowel function was assessed using the low anterior resection syndrome (LARS) score a minimum of one year following surgery. The length of remnant rectum was measured on postoperative MRI of the pelvis and was correlated with the risk of having major LARS.

RESULTS

Overall, major LARS was observed in 38 per cent of patients. In the patients who underwent surgery alone, major LARS was reported by 27 per cent, and a larger remnant rectum was associated with a better functional outcome. In contrast, 80 per cent of patients who underwent combined preoperative chemoradiotherapy and surgery reported having major LARS. No association between the length of remnant rectum and the risk of major LARS was observed in patients treated with combined neoadjuvant therapy and surgery.

CONCLUSION

Both the length of remnant rectum and preoperative chemoradiotherapy had a major impact on the severity of bowel dysfunction after restorative rectal cancer surgery. No functional benefit from an irradiated rectal remnant was observed.

Long-term function and morphology of the anal sphincters and the pelvic floor after primary repair of obstetric anal sphincter injury

AIM

More than 50% of women experience deteriorating continence over time following primary repair of obstetric anal sphincter injuries. The objectives of this study were to assess the function and morphology of the anal sphincters and pelvic floor in women with long-term faecal incontinence after sphincter repair (primary end-point) and to evaluate their correlation with severity of incontinence (secondary end-point).

METHOD

The participants in this prospective study were recruited from a cohort of all women who sustained third or fourth degree obstetric sphincter injury reconstruction (cases) from January 1976 to November 1991. The women who delivered immediately before and after each case, without sustaining obstetric damage, were included as controls. Cases and controls were stratified into three categories: (i) continent; (ii) minor incontinence; and (iii) severe incontinence. The function and morphology of the anal sphincters and pelvic floor were evaluated by MRI, three-dimensional endoanal ultrasonography and anorectal physiology tests.

RESULTS

Fifty-nine women (29 cases/30 controls; mean age 51/53 years; mean follow-up 23.7/24.1 years, respectively) were assessed. Morphologically, cases had a significantly shorter anterior external anal sphincter length compared with controls when evaluated by three-dimensional endoanal ultrasonography (8.6 vs 10.2 mm; P = 0.03). Functionally, cases with severe incontinence had a significantly shorter anterior sphincter length compared with cases with minor incontinence (7.7 vs 10.4 mm; P = 0.04). No correlation could be found between anal pressures and severity of incontinence in the case group.

CONCLUSIONS

Cases had a significantly shorter anterior external anal sphincter length. Functionally, anterior sphincter length correlated with increased severity of incontinence.

Neuromuscular adaptations to long-term progressive resistance training translates to improved functional capacity for people with multiple sclerosis and is maintained at follow-up

Background:

Progressive resistance training (PRT) is acknowledged to effectively improve muscle strength for people with multiple sclerosis (PwMS), but diverging results exist regarding whether such improvements translates to improved functional capacity, possibly relating to insufficient duration and/or intensity in some previous studies.

Objective:

The purpose of this study was to evaluate potential changes in functional capacity and neuromuscular function after 24 weeks of supervised PRT, and whether improvements are maintained after an additional 24 weeks of self-guided exercise.

Methods:

This study was a randomised controlled trial, with a training group and a waitlist group undergoing supervised PRT for 24 weeks initially or after 24 weeks of habitual lifestyle, respectively. Functional capacity, isometric muscle strength of knee extensors and flexors, neural drive and thigh muscle cross-sectional area was measured at baseline, after 24 and 48 weeks.

Results:

The training group significantly improved neuromuscular function of the knee extensors and flexors, which translated to improvements in functional capacity. Furthermore, the improved functional capacity was maintained after 24 weeks of self-guided physical activity. The waitlist group produced similar patterns of changes after PRT.

Conclusion:

Compelling evidence is provided, that PRT performed over sufficiently long periods, improves functional capacity, likely due to neuromuscular adaptations.