Computed Tomography-Based Body Composition Is Not Consistently Associated with Outcome in Older Patients with Colorectal Cancer

Background

Current literature is inconsistent in the associations between computed tomography (CT)‐based body composition measures and adverse outcomes in older patients with colorectal cancer (CRC). Moreover, the associations with consecutive treatment modalities have not been studied. This study compared the associations of CT‐based body composition measures with surgery‐ and chemotherapy‐related complications and survival in older patients with CRC.

Materials and Methods

A retrospective single‐center cohort study was conducted in patients with CRC aged ≥65 years who underwent elective surgery between 2010 and 2014. Gender‐specific standardized scores of preoperative CT‐based skeletal muscle (SM), muscle density, intermuscular adipose tissue (IMAT), visceral adipose tissue (VAT), subcutaneous adipose tissue, IMAT percentage, SM/VAT, and body mass index (BMI) were tested for their associations with severe postoperative complications, prolonged length of stay (LOS), readmission, and dose‐limiting toxicity using logistic regression and 1‐year and long‐term survival (range 3.7–6.6 years) using Cox regression. Bonferroni correction was applied to account for multiple testing.

Results

The study population consisted of 378 patients with CRC with a median age of 73.4 (interquartile range 69.5–78.4) years. Severe postoperative complications occurred in 13.0%, and 39.4% of patients died during follow‐up. Dose‐limiting toxicity occurred in 77.4% of patients receiving chemotherapy (n = 53). SM, muscle density, VAT, SM/VAT, and BMI were associated with surgery‐related complications, and muscle density, IMAT, IMAT percentage, and SM/VAT were associated with long‐term survival. After Bonferroni correction, no CT‐based body composition measure was significantly associated with adverse outcomes. Higher BMI was associated with prolonged LOS.

Conclusion

The associations between CT‐based body composition measures and adverse outcomes of consecutive treatment modalities in older patients with CRC were not consistent or statistically significant.

Implications for Practice

Computed tomography (CT)‐based body composition, including muscle mass, muscle density, and intermuscular, visceral, and subcutaneous adipose tissue, showed inconsistent and nonsignificant associations with surgery‐related complications, dose‐limiting toxicity, and overall survival in older adults with colorectal cancer. This study underscores the need to verify whether CT‐based body composition measures are worth implementing in clinical practice.

Colorectal cancer is prevalent in older individuals. This article compares the associations of computed tomography‐based body composition measures with surgery‐ and chemotherapy‐related complications and survival in older patients with colorectal cancer.

Possible Preventable Causes of Unplanned Readmission After Elective Liver Resection, Results from a Non-academic Referral HPB Center

INTRODUCTION

Unplanned readmission is a common event after liver resection, and it is a burden for both patients and healthcare policy makers. This study evaluates the incidence of and reasons for unplanned readmission after liver resection, in order to identify possible preventable causes.

METHODS

In this single-center cohort study, data from patients who underwent liver resection for both malignant and benign indications from 2001 to 2016 at our institute were collected from a database with prospective data. Readmissions were analyzed for their reasons and risk factors. Patients with general complaints with no specific complications were categorized as failure to thrive.

RESULTS

In 406 patients, the readmission rate was 11.6%. Most patients were readmitted because of failure to thrive (35%), deep and superficial surgical site infection (28%), or cardiopulmonary complications (15%). A multivariate analysis revealed that unplanned readmission was associated with the occurrence of complications during index admission-with an odds ratio of 4.69 (CI 2.41-9.12, p < 0.001).

CONCLUSION

Readmission occurs in more than 1 in 10 patients after liver resection, and it is associated with a complicated course during index admission. One-third of readmissions occur because of failure to thrive and might be preventable. Future research in strategies to reduce readmission rates should focus on both the prevention of complications during index admission and programs at the interface between primary and secondary care.

Surgical treatment for non-parasitic liver cysts improves quality of life

BACKGROUND&PURPOSE

Liver cysts occur frequently. Most are harmless, however some carry a significant patient burden. Optimizing treatment strategy is complicated as needs differ between patients. The current study assesses the effect of surgery on quality of life (QoL) of patients with non-parasitic liver cysts.

METHODS

A retrospective cohort study of all patients who underwent surgery for non-parasitic liver cysts in three major Dutch medical centers from 1993 to 2017. Patient characteristics and surgery related variables were collected from the electronic patient file. QoL was measured before and after surgery using the EORTC QLQ-C30. Summary scores (SumSc) were calculated and compared to reference values of the general population. Multivariate analysis using logistic regression was performed for identifying outcome related factors. Increase of ≥ 10% in SumSc was defined as clinically relevant.

MAIN FINDINGS

Eighty-eight of 132 eligible patients (67%) completed two QoL assessments. Respondents demonstrated significant improvement in the global health status, on all 5 functional scales (all p ≤ 0.005), on all 9 symptom scales after surgery (all p < 0.05), and on SumSc (p < 0.001) to levels similar or better than the general population. Patients with complications demonstrated a significant QoL gain (p < 0.05), and reported a similar postoperative status compared to patients without complications (p = 0.74). QoL gain for patients who underwent open and laparoscopic cyst fenestration were similar (p = 0.08). Multivariate analysis of SumSc found mechanical complaints as significant factor for ≥ 10% SumSc increase (OR 0.11, 95% CI (0.02-0.55).

CONCLUSIONS

Surgery is a safe and effective strategy to significantly improve QoL in patients with symptomatic liver cysts.

Impact and risk factors for clinically relevant surgery-related muscle loss in patients after major abdominal cancer surgery: study protocol for a prospective observational cohort study (MUSCLE POWER)

<p class="abstract"><strong>Background:</strong> Surgery-related muscle loss (SRML) occurs in at least one out of three cancer patients within one week after major surgery. Though, this important phenomenon has hardly been investigated.</p><p class="abstract"><strong>Methods:</strong> The MUSCLE POWER is a prospective, observational cohort study that investigates the presence, impact, and predictors for clinically relevant SRML in 178 cancer patients after major abdominal surgery using ultrasound measurements, squeeze and force measurements, and QoL questionnaires. Primary endpoint is the proportion of patients with clinically relevant SRML defined as ≥5% muscle loss within one week after surgery, measured by the cross-sectional area (CSA) of three different muscles: m. biceps brachii, m. rectus femoris, and m. vastus intermedius. Possible correlation with QoL and fatigue up to six months after surgery will be investigated. Daily physical activity during hospital stay will be monitored by a motility tracker, and protein intake will be monitored by a dietician. Possible predictors for clinically relevant SRML—consisting of age ≥65 years, preoperative diabetes, preoperative sarcopenia, major postoperative complications (Clavien-Dindo ≥III), insufficient physical activity, and insufficient postoperative protein intake—will be investigated with a multivariable logistic regression analyses with a backward stepwise approach. Variables with a <em>p</em>&lt;0.05 will be retrained in the final multivariable model.</p><p class="abstract"><strong>Discussion: </strong>The MUSCLE POWER investigates the presence and impact of clinically relevant SRML in cancer patients after major abdominal surgery. Crucial information regarding possible predictors for clinically relevant SRML can be used in future intervention studies to prevent postoperative muscle loss and subsequently improve postoperative outcome and QoL.</p><p><strong>Trial Registration: </strong>Medical Ethics Committee of the University Medical Center Groningen, the Netherlands (METc2018/361, version 3.0, January 21, 2019), and Netherlands Trial Register ([NTR], NTR NL7505, version 1.0, February 7, 2019).</p>

Safety of radiofrequency ablation in patients with locally advanced, unresectable pancreatic cancer: A phase II study

INTRODUCTION

Radiofrequency ablation (RFA) has been proposed as a new treatment option for locally advanced, unresectable pancreatic cancer (LAPC). In preparation of a randomized controlled trial (RCT), the aim of this phase II study was to assess the safety of RFA for patients with LAPC.

MATERIALS AND METHODS

Patients diagnosed with LAPC confirmed during surgical exploration between November 2012 and April 2014 were eligible for inclusion. RFA probes were placed under ultrasound guidance with a safety margin of at least 10 mm from the duodenum and 15 mm from the portomesenteric vessels. During RFA, the duodenum was continuously perfused with cold saline to reduce risk for thermal damage. Primary outcome was defined as the amount of major complications (Clavien-Dindo grade ≥III). RFA-related complications were predefined as: pancreatic fistula, pancreatitis, thermal damage to the portomesenteric vessels and duodenal perforation.

RESULTS

In total, 17 patients underwent RFA. Delayed gastric emptying (DGE) requiring endoscopic feeding tube placement occurred in 4 patients (24%) as only major complication. Five patients (29%) had a major complication other than DGE. One (6%) RFA-related major complications occurred. One patient (6%) died due to complications from a biliary leak following hepaticojejunostomy. After evaluation of the first 5 patients, gastrojejunostomy was no longer performed routinely. Since then severe DGE seemed to occur less (3/5 vs. 3/12 grade C DGE).

CONCLUSION

RFA is a major, but safe procedure for patients with LAPC if performed with strict predefined safety criteria. A RCT is currently investigating the true effectiveness of RFA in patients with LAPC.

Robot-Assisted Laparoscopic Resection of a Todani Type II Choledochal Malformation

Choledochal malformation (CM) comprise various congenital cystic dilatations of the extrahepatic and/or intrahepatic biliary tree. CM is classified into five different types. Our case describes a 58-year-old man presenting with acute abdominal pain. Further examination showed a Todani type II CM. Treatment for type II is complete cyst excision without the need for an extrahepatic bile duct resection. A robot-assisted laparoscopic resection of the CM was performed and the patient recovered without complications. Pathology results showed a Todani type II malformation in which complete squamous metaplasia has occurred. In this paper, we report, to the best of our knowledge, the first description of a robot-assisted laparoscopic resection of a type II CM.

Feasibility of a national expert panel to determine resectability in patients with initially unresectable colorectal cancer liver metastases (CRLM)

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Background: Decision on optimal treatment strategy for CRLM remains complex because uniform (un)resectability criteria are lacking. We hypothesize that the use of an expert panel can improve the identification of patients with potentially resectable CRLM. The Dutch Colorectal Cancer Group (DCCG) Expert Panel was established in conjunction with the CAIRO5 study (Huiskens J et al. BMC Cancer 2015), a multicenter, randomized, phase-3 trial, investigating optimal systemic induction treatment in patients with initially unresectable CRLM. Here, we present the feasibility of this panel. Methods: The DCCG Expert Panel consists of 13 liver surgeons and 4 radiologists. Consensus was reached on predefined (un)resectability criteria at baseline. An online platform allowed resectability-assessment by 3 surgeons in case of inter-surgeon agreement, and 5 surgeons if they disagreed. CRLM were assessed as 1) resectable 2) potentially resectable, or 3) permanently unresectable. Patients with initially unresectable CRLM were evaluated at baseline and subsequently every 2 months as long as CRLM were considered potentially resectable. Results: Overall, 397 panel evaluations in 183 patients were analyzed. Median time to panel conclusion was 7 days (IQR 5-11 days) and 204 (51%) evaluations showed inter-surgeon disagreement, with major disagreement (resectable versus permanently unresectable) in 24 (14%) and 12 (29%) evaluations after 2 and 4 months of systemic treatment. Ultimately, 84 (79%) patients with resectable CRLM underwent resection and 23 (27%) resections included portal vein embolization or 2-stage procedures. In resectable CRLM with inter-surgeon agreement versus disagreement, R0 resection was achieved in 39 (75%) versus 28 (52%) patients, p = 0.013. Median time to recurrence was similar between resections with panel agreement versus disagreement, 8 versus 6 months, p = 0.447. Conclusions: This study shows the feasibility of a national Liver Expert Panel for prospective resectability assessment of patients with initially unresectable CRLM. High inter-surgeon disagreement supports the use of a panel. We aim to further validate the panel with outcome parameters. Clinical trial information: NCT02162563.

Costs and quality of life in a randomized trial comparing minimally invasive and open distal pancreatectomy (LEOPARD trial)

Background

Minimally invasive distal pancreatectomy decreases time to functional recovery compared with open distal pancreatectomy, but the cost‐effectiveness and impact on disease‐specific quality of life have yet to be established.

Methods

The LEOPARD trial randomized patients to minimally invasive (robot‐assisted or laparoscopic) or open distal pancreatectomy in 14 Dutch centres between April 2015 and March 2017. Use of hospital healthcare resources, complications and disease‐specific quality of life were recorded up to 1 year after surgery. Unit costs of hospital healthcare resources were determined, and cost‐effectiveness and cost–utility analyses were performed. Primary outcomes were the costs per day earlier functional recovery and per quality‐adjusted life‐year.

Results

All 104 patients who had a distal pancreatectomy (48 minimally invasive and 56 open) in the trial were included in this study. Patients who underwent a robot‐assisted procedure were excluded from the cost analysis. Total medical costs were comparable after laparoscopic and open distal pancreatectomy (mean difference €–427 (95 per cent bias‐corrected and accelerated confidence interval €–4700 to 3613; P = 0·839). Laparoscopic distal pancreatectomy was shown to have a probability of at least 0·566 of being more cost‐effective than the open approach at a willingness‐to‐pay threshold of €0 per day of earlier recovery, and a probability of 0·676 per additional quality‐adjusted life‐year at a willingness‐to‐pay threshold of €80 000. There were no significant differences in cosmetic satisfaction scores (median 9 (i.q.r. 5·75–10) versus 7 (4–8·75); P = 0·056) and disease‐specific quality of life after minimally invasive (laparoscopic and robot‐assisted procedures) versus open distal pancreatectomy.

Conclusion

Laparoscopic distal pancreatectomy was at least as cost‐effective as open distal pancreatectomy in terms of time to functional recovery and quality‐adjusted life‐years. Cosmesis and quality of life were similar in the two groups 1 year after surgery.

Patient's Skeletal Muscle Radiation Attenuation and Sarcopenic Obesity are Associated with Postoperative Morbidity after Neoadjuvant Chemoradiation and Resection for Rectal Cancer

BACKGROUND/AIMS

To investigate the relation between skeletal muscle measurements (muscle mass, radiation attenuation, and sarcopenic obesity), postoperative morbidity, and survival after treatment of locally advanced rectal cancer.

METHODS

This explorative retrospective study identified 99 consecutive patients who underwent neoadjuvant chemoradiation and surgery between January 2007 and May 2012. Skeletal muscle mass was measured as total psoas area and total abdominal muscle area (TAMA) at 3 anatomical levels using the patient's preoperative computed tomography scan. Radiation attenuation was measured using corresponding mean Hounsfield units for TAMA. Sarcopenic obesity was defined as body mass index above 25 kg·m-2 combined with skeletal muscle mass index below the sex-specific median. Postoperative complications were graded by using the -Clavien-Dindo classification.

RESULTS

Twenty-five patients (25.3%) developed a grade 3-5 complication. Lower radiation attenuation was independently associated with overall (p = 0.003) and grade 3-5 complications (p = 0.002). Sarcopenic obesity was associated with overall complications (all p < 0.05). Skeletal muscle measurements and survival were not significantly related.

CONCLUSION

Radiation attenuation was associated with overall and grade 3-5 postoperative morbidity after neoadjuvant chemoradiation and non-laparoscopic resection for rectal cancer. Sarcopenic obesity was associated with overall complications.

Signet Ring Cell Carcinoma of the Ampulla of Vater: A Rare Histopathological Variant

Signet ring cell carcinoma (SRCC) of the ampulla of Vater is an extremely rare tumor. Our case describes a 45-year-old female presenting with jaundice and pruritus. Computed tomography, endoscopy, and endoscopic retrograde cholangiopancreatography showed a tumor of the ampulla of Vater without distant metastasis. Histological biopsy confirmed a malignant tumor with SRCC characteristics and immunohistochemical staining revealed a mixed type profile (both intestinal and pancreatobiliary characteristics). A pylorus-preserving pancreatoduodenectomy was performed and the patient recovered without complications. Pathology results concluded a pT2N0 ampullary SRCC. SRCC of the ampulla of Vater is known to be highly malignant. After 13 months of follow-up, our patient showed no signs of recurrence.

Tumor-stroma ratio as prognostic factor for survival in rectal adenocarcinoma: A retrospective cohort study

AIM

To evaluate the prognostic value of the tumor-stroma ratio (TSR) in rectal cancer.

METHODS

TSR was determined on hematoxylin and eosin stained histological sections of 154 patients treated for rectal adenocarcinoma without prior neoadjuvant treatment in the period 1996-2006 by two observers to assess reproducibility. Patients were categorized into three categories: TSR-high [carcinoma percentage (CP) ≥ 70%], TSR-intermediate (CP 40%, 50% and 60%) and TSR-low (CP ≤ 30%). The relation between categorized TSR and survival was analyzed using Cox proportional hazards model.

RESULTS

Thirty-six (23.4%) patients were scored as TSR-low, 70 (45.4%) as TSR-intermediate and 48 (31.2%) as TSR-high. TSR had a good interobserver agreement (κ = 0.724, concordance 82.5%). Overall survival (OS) and disease free survival (DFS) were significantly better for patients with a high TSR (P = 0.01 and P = 0.02, respectively). A similar association existed for disease specific survival (P = 0.06). In multivariate analysis, patients without lymph node metastasis and an intermediate TSR had a higher risk of dying from rectal cancer (HR = 5.27, 95%CI: 1.54-18.10), compared to lymph node metastasis negative patients with a high TSR. This group also had a worse DFS (HR = 6.41, 95%CI: 1.84-22.28). An identical association was seen for OS. These relations were not seen in lymph node metastasis positive patients.

CONCLUSION

The TSR has potential as a prognostic factor for survival in surgically treated rectal cancer patients, especially in lymph node negative cases.

The Effect of Unenhanced MRI on the Surgeons' Decision-Making Process in Females with Suspected Appendicitis

Background

This prospective study evaluated the impact of the results of unenhanced magnetic resonance imaging (MRI) on the surgeon’s diagnosis of acute appendicitis in potentially fertile females.

Methods

112 female patients, aged 12–55, with suspected appendicitis underwent MRI of the abdomen. At three defined intervals; admission and clinical re-evaluation before and after revealing the MRI results, the surgeon recorded the attendance of each patient in operative treatment, observation or discharge. Appendicitis was confirmed or declined by pathology or by telephone follow-up in case of non-intervention.

Findings

Appendicitis was confirmed in 29 of 112 patients. At admission the surgeon’s disposition had a sensitivity of 97 % and specificity of 29 %. After knowing the MRI results, sensitivity was 97 % and specificity 64 %. The sensitivity and specificity of MRI alone were 89 and 100 %, with a negative and positive predictive value of 96 and 100 %, respectively.

Conclusion

We believe that MRI should perhaps be standard in all female patients during their reproductive years with suspected appendicitis. It avoids an operation in 32 % of cases and allows earlier planning for patients with an equivocal clinical picture. Trial number: OND1292733 (Narcis.nl).

An evaluation of the validity of the pre-operative oxygen uptake efficiency slope as an indicator of cardiorespiratory fitness in elderly patients scheduled for major colorectal surgery

This study aimed to investigate the validity of the oxygen uptake efficiency slope as an objective and submaximal indicator of cardiorespiratory fitness in elderly patients scheduled for major colorectal surgery. Patients ≥ 60 years of age, with a metabolic equivalent score using the Veterans Activity Questionnaire ≤ 7 and scheduled for major colorectal surgery participated in a pre-operative cardiopulmonary exercise test. The oxygen uptake efficiency slope was calculated up to different exercise intensities, using 100%, 90% and 80% of the exercise data. Data from 71 patients (47 men, mean (SD) age 75.2 (6.7) years) were analysed. The efficiency slope obtained from all the data was statistically significantly different from the values when 90% (p = 0.027) and 80% (p = 0.023) of the data were used. The 90% and 80% values did not differ significantly from each other (p = 0.152). Correlations between the oxygen uptake efficiency slope and the peak oxygen uptake ranged from 0.816 to 0.825 (all p < 0.001), and correlations between oxygen uptake efficiency slope and the ventilatory anaerobic threshold ranged from 0.793 to 0.805 (all p < 0.001). Receiver operating characteristic curves showed that the oxygen uptake efficiency slope is a sensitive and specific predictor of a peak oxygen uptake ≤ 18.2 ml.kg^-1 .min^-1 , with an area under the curve (95%CI) of 0.876 (0.780-0.972, p < 0.001) and a ventilatory anaerobic threshold ≤ 11.1 ml.kg^-1 .min^-1 , with an area under the curve (95%CI) of 0.828 (0.726-0.929, p < 0.001). These correlations suggest that the oxygen uptake efficiency slope provides a valid (sub)maximal measure of cardiorespiratory fitness in these patients, and the predictive ability described indicates that it might help discriminate patients at higher risk of postoperative morbidity. However, future research should investigate the prognostic value of the oxygen uptake efficiency slope for postoperative outcomes.

Survival analysis of the CEAwatch multicentre clustered randomized trial

BACKGROUND

The CEAwatch randomized trial showed that follow-up with intensive carcinoembryonic antigen (CEA) monitoring (CEAwatch protocol) was better than care as usual (CAU) for early postoperative detection of colorectal cancer recurrence. The aim of this study was to calculate overall survival (OS) and disease-specific survival (DSS).

METHODS

For all patients with recurrence, OS and DSS were compared between patients detected by the CEAwatch protocol versus CAU, and by the method of detection of recurrence, using Cox regression models.

RESULTS

Some 238 patients with recurrence were analysed (7·5 per cent); a total of 108 recurrences were detected by CEA blood test, 64 (55·2 per cent) within the CEAwatch protocol and 44 (41·9 per cent) in the CAU group (P = 0·007). Only 16 recurrences (13·8 per cent) were detected by patient self-report in the CEAwatch group, compared with 33 (31·4 per cent) in the CAU group. There was no significant improvement in either OS or DSS with the CEAwatch protocol compared with CAU: hazard ratio 0·73 (95 per cent 0·46 to 1·17) and 0·78 (0·48 to 1·28) respectively. There were no differences in survival when recurrence was detected by CT versus CEA measurement, but both of these methods yielded better survival outcomes than detection by patient self-report.

CONCLUSION

There was no direct survival benefit in favour of the intensive programme, but the CEAwatch protocol led to a higher proportion of recurrences being detected by CEA-based blood test and reduced the number detected by patient self-report. This is important because detection of recurrence by blood test was associated with significantly better survival than patient self-report, indirectly supporting use of the CEAwatch protocol.

Randomized clinical trial of open versus laparoscopic left lateral hepatic sectionectomy within an enhanced recovery after surgery programme (ORANGE II study)

BACKGROUND

Laparoscopic left lateral sectionectomy (LLLS) has been associated with shorter hospital stay and reduced overall morbidity compared with open left lateral sectionectomy (OLLS). Strong evidence has not, however, been provided.

METHODS

In this multicentre double-blind RCT, patients (aged 18-80 years with a BMI of 18-35 kg/m2 and ASA fitness grade of III or below) requiring left lateral sectionectomy (LLS) were assigned randomly to OLLS or LLLS within an enhanced recovery after surgery (ERAS) programme. All randomized patients, ward physicians and nurses were blinded to the procedure undertaken. A parallel prospective registry (open non-randomized (ONR) versus laparoscopic non-randomized (LNR)) was used to monitor patients who were not enrolled for randomization because of doctor or patient preference. The primary endpoint was time to functional recovery. Secondary endpoints were length of hospital stay (LOS), readmission rate, overall morbidity, composite endpoint of liver surgery-specific morbidity, mortality, and reasons for delay in discharge after functional recovery.

RESULTS

Between January 2010 and July 2014, patients were recruited at ten centres. Of these, 24 patients were randomized at eight centres, and 67 patients from eight centres were included in the prospective registry. Owing to slow accrual, the trial was stopped on the advice of an independent Data and Safety Monitoring Board in the Netherlands. No significant difference in median (i.q.r.) time to functional recovery was observed between laparoscopic and open surgery in the randomized or non-randomized groups: 3 (3-5) days for OLLS versus 3 (3-3) days for LLLS; and 3 (3-3) days for ONR versus 3 (3-4) days for LNR. There were no significant differences with regard to LOS, morbidity, reoperation, readmission and mortality rates.

CONCLUSION

This RCT comparing open and laparoscopic LLS in an ERAS setting was not able to reach a conclusion on time to functional recovery, because it was stopped prematurely owing to slow accrual. Registration number: NCT00874224 ( https://www.clinicaltrials.gov).

Ex vivo sentinel lymph node mapping in colorectal cancer using a magnetic nanoparticle tracer to improve staging accuracy: a pilot study

AIM

Nodal status is the most important prognostic factor in colorectal cancer (CRC). Small occult metastases may remain undetected on conventional histopathological examination, potentially resulting in undertreatment. Ex vivo sentinel lymph node mapping (SLNM) can be used to improve the accuracy of nodal staging, but the currently used tracers suffer from drawbacks, which hamper implementation of the technique in routine clinical practice. Magnetic tracers are the optimal size for sentinel lymph node (SLN) retention and allow objective quantitative selection of SLNs; they therefore have great potential for SLNM in CRC. The study evaluates the feasibility of ex vivo magnetic SLNM and compares the performance of this technique with blue dye SLNM.

METHOD

Twenty-eight ex vivo SLNM procedures were performed in 27 histological node-negative patients with CRC using a magnetic tracer and blue dye. A magnetometer was used to select magnetic SLNs after formalin fixation of the CRC specimen. Both magnetic and blue SLNs were subjected to serial sectioning and immunohistochemical staining to reveal occult metastases.

RESULTS

At least one SLN was successfully identified in 27/28 (96%) and 25/28 (89%) of the cases with the magnetic technique and blue dye. Isolated tumour cells were detected in 10 patients. This was predicted with 100% sensitivity and accuracy using the magnetic technique, and with 91% sensitivity and 96% accuracy using the blue dye technique.

CONCLUSION

This study demonstrates that ex vivo magnetic SLNM is a feasible technique for use in routine clinical practice, improving nodal staging accuracy of CRC patients.

Meta-analysis of sentinel lymph node biopsy in breast cancer using the magnetic technique

BACKGROUND

The standard for sentinel lymph node biopsy (SLNB), the dual technique (radiolabelled tracer and blue dye), has several drawbacks. A novel magnetic technique without these drawbacks has been evaluated in a number of clinical trials. It uses a magnetic tracer and a handheld magnetometer to identify and excise sentinel lymph nodes. A systematic review and meta-analysis was performed to assess the performance and utility of the magnetic in comparison to the standard technique.

METHODS

MEDLINE, PubMed, Embase and the Cochrane online literature databases were used to identify all original articles evaluating the magnetic technique for SLNB published up to April 2016. Studies were included if they were prospectively conducted clinical trials comparing the magnetic with the standard technique for SLNB in patients with breast cancer.

RESULTS

Seven studies were included. The magnetic technique was non-inferior to the standard technique (z = 3·87, P < 0·001), at a 2 per cent non-inferiority margin. The mean identification rates for the standard and magnetic techniques were 96·8 (range 94·2-99·0) and 97·1 (94·4-98·0) per cent respectively (risk difference (RD) 0·00, 95 per cent c.i. -0·01 to 0·01; P = 0·690). The total lymph node retrieval was significantly higher with the magnetic compared with the standard technique: 2113 (1·9 per patient) versus 2000 (1·8 per patient) (RD 0·05, 0·03 to 0·06; P = 0·003). False-negative rates were 10·9 (range 6-22) per cent for the standard technique and 8·4 (2-22) per cent for the magnetic technique (RD 0·03, 0·00 to 0·06; P = 0·551). The mean discordance rate was 3·9 (range 1·7-6·9) per cent.

CONCLUSION

The magnetic technique for SLNB is non-inferior to the standard technique, with a high identification rate but with a significantly higher lymph node retrieval rate.

Skeletal muscle mass and quality as risk factors for postoperative outcome after open colon resection for cancer

BACKGROUND

The prevalence of colorectal cancer in the elderly is increasing and, therefore, surgical interventions with a risk of potential complications are more frequently performed. This study investigated the role of low skeletal muscle mass (sarcopenia), muscle quality, and the sarcopenic obesity as prognostic factors for postoperative complications and survival in patients with resectable colon cancer.

METHODS

We conducted a retrospective chart review of 91 consecutive patients who underwent an elective open colon resection for cancer with primary anastomosis between 2011 and 2013. Skeletal muscle mass was measured as total psoas area (TPA) and total abdominal muscle area (TAMA) at three anatomical levels on the preoperative CT scan. Skeletal muscle quality was measured using corresponding mean Hounsfield units (HU) for TAMA. Their relation with complications (none vs one or more), severe complications, and survival was analyzed.

RESULTS

The study included 91 patients with a mean age of 71.2 ± 9.7 years. Complications were noted in 55 patients (60 %), of which 15 (16.4 %) were severe. Lower HU for TAMA, as an indicator for impaired skeletal muscle quality, was an independent risk factor for one or more complications (all P ≤ 0.002), while sarcopenic obesity (TPA) was an independent risk factor for severe complications (all P ≤ 0.008). Sarcopenia was an independent predictor of worse overall survival (HR 8.54; 95 % confidence interval (CI) 1.07-68.32).

CONCLUSION

Skeletal muscle quality is a predictor for overall complications, whereas sarcopenic obesity is a predictor for severe postoperative complications after open colon resection for cancer. Sarcopenia on itself is a predictor for worse overall survival.

Phantom study quantifying the depth performance of a handheld magnetometer for sentinel lymph node biopsy

PURPOSE

The use of a magnetic nanoparticle tracer and handheld magnetometer for sentinel lymph node biopsy (SLNB) was recently introduced to overcome drawbacks associated with the use of radioisotope tracers. Unlike the gamma probe, the used magnetometers are not only sensitive to the tracer, but also the diamagnetic human body. This potentially limits the performance of the magnetometer when used clinically.

METHODS

A phantom, mimicking the magnetic and mechanical properties of the human axilla, was constructed. The depth performance of two current generation magnetometers was evaluated in this phantom. LN-phantoms with tracer uptake ranging from 5 to 500μg iron were placed at clinically relevant depths of 2.5, 4 and 5.5cm. Distance-response curves were obtained to quantify the depth performance of the probes.

RESULTS

The depth performance of both probes was limited. In the absence of diamagnetic material and forces on the probe (ideal conditions) a LN-phantom with high uptake (500μg iron) could first be detected at 3.75cm distance. In the phantom, only superficially placed LNs (2.5cm) with high uptake (500μg iron) could be detected from the surface. The penetration depth was insufficient to detect LNs with lower uptake, or which were located deeper.

CONCLUSION

The detection distance of the current generation magnetometers is limited, and does not meet the demands formulated by the European Association for Nuclear Medicine for successful transcutaneous SLN localization. Future clinical trials should evaluate whether the limited depth sensitivity is of influence to the clinical outcome of the SLNB procedure.

Preoperative radiochemotherapy versus immediate surgery for resectable and borderline resectable pancreatic cancer (PREOPANC trial): study protocol for a multicentre randomized controlled trial

Background

Pancreatic cancer is the fourth largest cause of cancer death in the United States and Europe with over 100,000 deaths per year in Europe alone. The overall 5-year survival ranges from 2–7 % and has hardly improved over the last two decades. Approximately 15 % of all patients have resectable disease at diagnosis, and of those, only a subgroup has a resectable tumour at surgical exploration. Data from cohort studies have suggested that outcome can be improved by preoperative radiochemotherapy, but data from well-designed randomized studies are lacking. Our PREOPANC phase III trial aims to test the hypothesis that median overall survival of patients with resectable or borderline resectable pancreatic cancer can be improved with preoperative radiochemotherapy.

Methods/design

The PREOPANC trial is a randomized, controlled, multicentric superiority trial, initiated by the Dutch Pancreatic Cancer Group. Patients with (borderline) resectable pancreatic cancer are randomized to A: direct explorative laparotomy or B: after negative diagnostic laparoscopy, preoperative radiochemotherapy, followed by explorative laparotomy. A hypofractionated radiation scheme of 15 fractions of 2.4 gray (Gy) is combined with a course of gemcitabine, 1,000 mg/m²/dose on days 1, 8 and 15, preceded and followed by a modified course of gemcitabine. The target volumes of radiation are delineated on a 4D CT scan, where at least 95 % of the prescribed dose of 36 Gy in 15 fractions should cover 98 % of the planning target volume. Standard adjuvant chemotherapy is administered in both treatment arms after resection (six cycles in arm A and four in arm B). In total, 244 patients will be randomized in 17 hospitals in the Netherlands. The primary endpoint is overall survival by intention to treat. Secondary endpoints are (R0) resection rate, disease-free survival, time to locoregional recurrence or distant metastases and perioperative complications. Secondary endpoints for the experimental arm are toxicity and radiologic and pathologic response.

Discussion

The PREOPANC trial is designed to investigate whether preoperative radiochemotherapy improves overall survival by means of increased (R0) resection rates in patients with resectable or borderline resectable pancreatic cancer.

Trial registration

Trial open for accrual: 3 April 2013

The Netherlands National Trial Register – NTR3709 (8 November 2012)

EU Clinical Trials Register – 2012-003181-40 (11 December 2012)

The state of the art in breast imaging using the Twente Photoacoustic Mammoscope: results from 31 measurements on malignancies

Objectives

Photoacoustic mammography is potentially an ideal technique, however, the amount of patient data is limited. To further our understanding of the in vivo performance of the method and to guide further research and development, we imaged 33 breast malignancies using the research system – the Twente Photoacoustic Mammoscope (PAM).

Methods

Thirty-one patients participated in this retrospective, observational study. The study and informed consent procedure were approved by the local ethics committee. PAM uses 1,064 nm light for excitation with a planar, 588-element, 1-MHz ultrasound array for detection. Photoacoustic lesion visibility and appearance were compared with conventional imaging (x-ray mammography and ultrasonography) findings, histopathology and patient demographics.

Results

Of 33 malignancies 32 were visualized with high contrast and good co-localization with conventional imaging. The contrast of the detected malignancies was independent of radiographic breast density, and size estimation was reasonably good with an average 28 % deviation from histology. However, the presence of contrast areas outside the malignant region is suggestive for low specificity of the current system. Statistical analyses did not reveal any further relationship between PAM results and patient demographics nor lesion characteristics.

Conclusions

The results confirm the high potential of photoacoustic mammography in future breast care.

Key Points

• Photoacoustic breast imaging visualizes malignancies with high imaging contrast.

• Photoacoustic lesion contrast is independent of the mammographically estimated breast density.

• No clear relationship exists between photoacoustic characteristics and lesion type, grade, etc.

• Photoacoustic specificity to breast cancer from some cases is not yet optimal.

Abstract P6-09-03: Time-dependent nomogram for risk of locoregional recurrence in early breast cancer patients: 10 year extension

Background

The objective of this study was to extent the recently developed and validated time-dependent logistic regression model and web-based nomogram. This nomogram is suitable for the annual long term risk prediction of locoregional recurrence (LRR) in individual breast cancer patients and clinical decision support with regard to the follow-up.

Methods

Women first diagnosed with early breast cancer between 2003-2006 in all Dutch hospitals were selected from the Netherlands Cancer Registry with five year of recurrence follow-up (n=37,230). Of the year 2003 follow-up was retrieved for ten years. In the first five years following primary breast cancer treatment 3.7% of the selected patients developed a LRR as a first event, in ten years 6.2%. Risk factors were determined using logistic regression and the risks were calculated per year, conditional on not being diagnosed with recurrence in the previous year. Discrimination and calibration were assessed. Bootstrapping was used for internal validation. Data on primary tumors diagnosed between 2007-2008 in 43 Dutch hospitals was used for external validation of the performance of the nomogram (n=12,308).

Results

The final model included the variables grade, size, multifocality, and nodal involvement of the primary tumor, and whether patients were treated with radio-, chemo- or hormone therapy. Model predictions were well calibrated. Estimates in the validation cohort did not differ significantly from the index cohort. The results were incorporated in a web-based nomogram. In 0.7% of the patients, the risk of LRR between year 5-10 was higher than the average risk of all patients in the first five years. All of these patients were aged below 50, had a tumour size larger than 2 cm, non-negative hormone status, received radiotherapy, but no hormone therapy and 19% developed a recurrence during ten years.

Conclusion/discussion

This validated and time-dependent nomogram for the prediction of annual LRR risks over ten years is simple to use and shows a good predictive ability in the Dutch population. It can be used as an instrument to identify patients with a low or high risk of LRR who might benefit from a less or more intensive and longer follow-up after breast cancer and to aid clinical decision-making for personalized follow-up.

Citation Format: Witteveen A, Vliegen IMH, Sonke GS, Klaase JM, IJzerman MJ, Siesling S. Time-dependent nomogram for risk of locoregional recurrence in early breast cancer patients: 10 year extension. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-09-03.