CT Findings of Hepatic Metastasis from Hepatoid Adenocarcinoma of the Rectum Mimicking Hepatocellular Carcinoma: A Case Report

Hepatoid adenocarcinoma (HAC) is a rare form of adenocarcinoma that is diagnosed based on immuno-histochemical findings reminiscent of hepatocellular carcinoma (HCC). The clinical characteristics of HAC include increased levels of serum alpha-fetoprotein and a poor prognosis due to early liver metastasis. In particular, diagnosing liver metastasis of HAC can be challenging owing to radiological findings similar to those of HCC. Although HAC can occur in various organs, the stomach is the most common site. We present the case of a 64-year-old femalewho presented with multiple tumors in the liver. During subsequent examination, rectal cancer was identified and diagnosed as HAC through a biopsy. Herein, we report this case along with a literature review.

Radial resection margin distinguishes between superficial versus deep resection in colorectal cancer: a retrospective study

Randomized studies showed that robotic surgery was short-term useful and safe for cancer patients. We investigated whether robots improve deep resection margins or superficial resection margins for radial resection margins in terms of short-term results. From an institutional database, we selected all superficial groups (≤ 3 mm) and deeper groups (≥ 4 mm) with rectal cancer treated with resection for a year. We evaluated the short-term post-operative 90-day outcomes on a radial resection size-based margin differentiation, including the first bowel movement, length of hospital stay, sepsis, and harvested lymph node. The main results were grades III-IV on the Clavien-Dindo scale and complications. We found 120 patients who had oncologic resection of rectal cancer; 42 patients with a superficial radial resection margin of ≤ 3 mm, all the following outcomes improved: the harvested lymph node, proximal resection margin, TME, flatus time, liquid diet duration, anastomotic leakage, and sepsis. Among these advantages were a reduced risk of metastasis and an overall reduction in local recurrence.

Development and Validation of a Post-Radiotherapy Prediction Model for Bowel Dysfunction After Rectal Cancer Resection

BACKGROUND & AIMS

The benefit of radiotherapy for rectal cancer is based largely on a balance between a decrease in local recurrence and an increase in bowel dysfunction. Predicting postoperative disability is helpful for recovery plans and early intervention. We aimed to develop and validate a risk model to improve the prediction of major bowel dysfunction after restorative rectal cancer resection with neoadjuvant radiotherapy using perioperative features.

METHODS

Eligible patients more than 1 year after restorative resection following radiotherapy were invited to complete the low anterior resection syndrome (LARS) score at 3 national hospitals in China. Clinical characteristics and imaging parameters were assessed with machine learning algorithms. The post-radiotherapy LARS prediction model (PORTLARS) was constructed by means of logistic regression on the basis of key factors with proportional weighs. The accuracy of the model for major LARS prediction was internally and externally validated.

RESULTS

A total of 868 patients reported a mean LARS score of 28.4 after an average time of 4.7 years since surgery. Key predictors for major LARS included the length of distal rectum, anastomotic leakage, proximal colon of neorectum, and pathologic nodal stage. PORTLARS had a favorable area under the curve for predicting major LARS in the internal dataset (0.835; 95% CI, 0.800-0.870, n = 521) and external dataset (0.884; 95% CI, 0.848-0.921, n = 347). The model achieved both sensitivity and specificity >0.83 in the external validation. In addition, PORTLARS outperformed the preoperative LARS score for prediction of major events.

CONCLUSIONS

PORTLARS could predict major bowel dysfunction after rectal cancer resection following radiotherapy with high accuracy and robustness. It may serve as a useful tool to identify patients who need additional support for long-term dysfunction in the early stage.

CLINICALTRIALS

gov, number NCT05129215.

Outcomes Following Recent and Distant Neoadjuvant Radiation in Rectal Cancer: An Institutional Retrospective Review and Analysis of NSQIP

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) is the standard of care in locally advanced rectal cancer (LARC). However, radiation therapy is thought to increase operative difficulty due to induction of fibrosis. Total neoadjuvant therapy (TNT) protocols increase the time between completion of radiation and surgical resection which may lead to increased operative difficulty and complications.

METHODS

A single institution retrospective review of patients ≥18 years with LARC undergoing nCRT from 2015 to 2022. Patients were dichotomized in 2 cohorts: <90 days from radiation to surgery (recent radiation), and ≥90 days from radiation to surgery (distant radiation). Institutional data was compared to National Surgical Quality Improvement Program (NSQIP) rectal cancer data from 2016 to 2020. Outcomes included intraoperative complications, 30-day morbidity, and oncologic outcomes.

RESULTS

One hundred forty-six institutional patients included, 120 had recent radiation, 26 had distant radiation. Thirty-day morbidity and intraoperative complications did not differ. There was greater radial margin positivity (7% vs. 24%), fewer lymph nodes harvested (17 ± 5 vs. 15 ± 6), and a lower rate of complete mesorectal dissection (88% vs. 65%,) in distant radiation patients 3059 patients were included in NSQIP analysis, 2029 completed radiation <90 days before surgery and 1030 without radiation 90 days before surgery. Patients without radiation 90 days preoperatively had more radial margin positivity (9.2% vs. 4.6%), organ space infection (8.6% vs. 6.4%), and pneumonia (2.2% vs. 0.9%).

CONCLUSION

The present study suggests that increased time between radiation and surgery results in more challenging dissection with less complete mesorectal dissection and increased radial margin positivity without increasing technical complications.

Perioperative and Oncological Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastasis of Rectal Origin

BACKGROUND

The peritoneum is a common metastatic site of colorectal cancer (CRC) and associated with worse oncological outcomes. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been shown to improve outcomes in selected patients. Studies have demonstrated significant difference in survival of patients with primary colon and rectal tumors both in local and in metastatic setting; but only few assessed outcomes of CRS/HIPEC for rectal and colon tumors. We studied the perioperative and oncological outcomes of patients undergoing CRS/HIPEC for rectal cancer.

METHODS

A retrospective analysis of a prospectively maintained database between 2009 and 2021 was performed.

RESULTS

199 patients underwent CRS/HIPEC for CRC. 172 patients had primary colon tumors and 27 had primary rectal tumors. Primary rectal location was associated with longer surgery (mean 4.32, hours vs 5.26 h, p = 0.0013), increased blood loss (mean 441cc vs 602cc, p = 0.021), more blood transfusions (mean 0.77 vs 1.37units, p = 0.026) and longer hospitalizations (mean 10 days vs 13 days, p = 0.02). Median disease-free survival (DFS) was shorter in rectal primary group; 7.03 months vs 10.9 months for colon primaries (p = 0.036). Overall survival was not statistically significant; 53.2 months for rectal and 60.8 months for colon primary tumors. Multivariate analysis indicated origin (colon vs rectum) and Peritoneal Cancer Index to be independently associated with DFS.

CONCLUSIONS

Patients with rectal carcinoma undergoing CRS/HIPEC for peritoneal metastasis had worse peri-operative and oncological outcomes. Overall survival was excellent in both groups. This data may be used for risk stratification when considering CRS/HIPEC for patients with rectal primary.

Clinical efficacy of Neoadjuvant Chemotherapy combined with Laparoscopic Surgery in patients with Middle and Low Rectal Cancer and its Effect on serum VEGF Levels and quality of life

Objective

To observe the clinical efficacy of neoadjuvant chemotherapy combined with laparoscopic surgery in patients with middle and low rectal cancer and its effect on serum VEGF level and quality of life.

Methods

Retrospective analysis was performed on 80 patients with middle and low rectal cancer admitted to Baoding No.1 Central Hospital from June 2018 to June 2020.They were randomly divided into two groups. Patients in the control group underwent laparoscopic radical rectal cancer surgery, while those in the experimental group underwent neoadjuvant chemotherapy before surgery. The differences of various surgical indicators between the two groups were compared. The incidence of surgical complications, the serum VEGF levels and the improvement of quality of life were compared. The differences in local recurrence, metastasis and overall survival with in two years after surgery were compared.

Results

The various surgical indicators of the experimental group were significantly better than the control group (p<0.05). After treatment, the VEGF levels in the experimental group were significantly lower than those in the control group (p=0.00), while the SF-36 score was significantly higher than that of the control group (p=0.00). The total incidence of surgical complications in experimental group was significantly lower (p=0.03), the local recurrence rate was significantly lower (p=0.02), and the overall survival rate was significantly higher than that in control group (p=0.04).

Conclusion

Neoadjuvant chemotherapy combined with laparoscopic surgery is superior to direct surgery alone in the treatment of middle and low rectal cancer and it needs to be promoted.

Diagnostic Performance of Rectal CT for Staging Rectal Cancer: Comparison with Rectal MRI and Histopathology

Purpose

To compare the diagnostic performance of rectal CT with that of high-resolution rectal MRI and histopathology in assessing rectal cancer.

Materials and Methods

Sixty-seven patients with rectal cancer who underwent rectal CT with rectal distension using sonographic gel and high-resolution MRI were enrolled in this study. The distance from the anal verge/anorectal junction, distance to the mesorectal fascia (MRF), extramural depth (EMD), extramesorectal lymph node (LN) involvement, extramural venous invasion (EMVI), and T/N stages in rectal CT/MRI were analyzed by two gastrointestinal radiologists. The CT findings of 20 patients who underwent radical surgery without concurrent chemoradiotherapy were compared using histopathology. Interclass correlations and kappa statistics were used.

Results

The distance from the anal verge/anorectal junction showed an excellent intraclass correlation between CT and MRI for both reviewers. For EMD, the distance to the MRF, presence of LNs, extramesorectal LN metastasis, EMVI, T stage, and intermodality kappa or weighted kappa values between CT and MRI showed excellent agreement. Among the 20 patients who underwent radical surgery, T staging, circumferential resection margin involvement, EMVI, and LN metastasis on rectal CT showed acceptable concordance rates with histopathology.

Conclusion

Dedicated rectal CT may be on par with rectal MRI in providing critical information to patients with rectal cancer.

surgery alone

BACKGROUND

Recent studies have shown that deficient mismatch repair (dMMR) rectal cancer may be related to treatment resistance, resulting in a worse prognosis than proficient MMR (pMMR) rectal cancer. The purpose of this study was to explore whether surgery plus other treatments (radiotherapy and chemotherapy) can bring more benefits to these patients than surgery alone.

METHODS

A retrospective study of 168 patients with rectal adenocarcinoma who underwent total mesorectal excision was conducted using immunohistochemical methods to determine MMR status and a propensity score matching model to minimize potential confounding factors between subgroups of patients with different treatment regimens. Kaplan-Meier analysis, log-rank tests, and Cox regression models were used to assess overall survival (OS) and disease-free survival (DFS) in patient subgroups.

RESULTS

Only 6.9% (n = 168) of patients in the total cohort had dMMR rectal adenocarcinoma, and the most common cause of dMMR was a PMS2 deletion (103, 61.3%). The median DFS of the surgery alone group was 45.7 months (IQR, 40.9 to 77.8), and the median DFS of the surgery plus other treatment group was 43.9 months (IQR, 14.2 to 80.1). The surgery alone group was superior to the surgery plus other treatment group (HR, 0.16; 95% CI, 0.07 to 0.38; p = 0.005). There was no significant difference in OS (45.8 (IQR, 41.0 to 79.8) vs. 45.9 (IQR, 38.5 to 80.3)) between the two groups (HR, 0.57; 95% CI, 0.23 to 1.40; p = 0.263).

CONCLUSIONS

For patients with locally advanced dMMR rectal adenocarcinoma, compared with surgery alone, surgery plus other treatment options (radiotherapy and chemotherapy) do not grant long-term survival benefits but rather shorten DFS.

A Cancer Cell Selective Replication Stress Nano Amplifier Promotes Replication Fork Catastrophe to Overcome Radioresistance

Replication stress (RS) induced by DNA damage plays a significant role in conferring the anticancer effects of radiotherapy and is tightly associated with radioresistance of cancer cells. Amplification of RS represents an effective approach to improving the efficacy of radiotherapy, although the development of selective RS amplifiers remains an unexplored frontier. We herein present an RS nano amplifier (RSNA) consisting of a catalytic FePt nanoparticle loaded with the chemotherapeutic doxorubicin (DOX), which selectively exacerbates RS in cancer cells by promoting replication fork (RF) catastrophe. RSNA converts the excessive reactive oxygen species (ROS) in cancer cells into oxygen, enhancing the DNA-damaging effects of radiotherapy to create more template lesions that impede RF progression in coalition with DOX. After radiation, ROS scavenging by RSNA accelerates RF progression through damaged template strands, increasing the frequency of RF collapse into double-strand breaks. Moreover, pretreatment with RSNA accumulates cancer cells in the S phase, exposing more RFs to radiation-induced RS. These effects of RSNA convergently maximize RS in cancer cells, effectively overcoming the radioresistance of cancer cells without affecting normal cells. Our study demonstrates the feasibility of selectively amplifying RS to boost radiotherapy.

Value of biplane transrectal ultrasonography plus micro-flow imaging in preoperative T staging and rectal cancer diagnosis in combination with CEA/CA199 and MRI

BACKGROUND

Rectal cancer is one of the most common malignant tumors and has a high incidence rate and fatality rate. Accurate preoperative T staging of rectal cancer is critical for the selection of appropriate rectal cancer treatment. Various pre-operative imaging methods are available, and the identification of the most accurate method for clinical use is essential for patient care. We investigated the value of biplane transrectal ultrasonography (TRUS) combined with MFI in preoperative staging of rectal cancer and explored the value of combining TRUS plus MFI with CEA/CA199 and MRI.

METHODS

A total of 87 patients from Daping Hospital with rectal cancer who underwent TRUS examination plus MFI were included. Grades of MFI were determined by Alder classification. Among the total patients, 64 underwent MRI and serum CEA/CA199 tests additionally within one week of TRUS. Pathological results were used as the gold standard for cancer staging. Concordance rates between TRUS, MRI, and CEA/CA199 for tumors at different stages were compared.

RESULTS

There were no significant differences between the Alder classification and pathological T staging. The concordance rate of TRUS and MFI for rectal cancer T staging was 72.4% (K = 0.615, p < 0.001). Serum CEA and CA199 levels were significantly different in tumors at different stages and increased progressively by pathological stage (p < 0.001); the accuracy rate was 71.88% (K = 0.599, p < 0.001), while that of MRI was 51.56% (K = 0.303, p < 0.001), indicating that TRUS had higher consistency in the preoperative T staging of rectal cancer. The combination of TRUS, MRI, and CEA/CA199 yielded an accuracy rate of 90.6%, which was higher than that of any method alone.

CONCLUSIONS

Preoperative T staging of rectal cancer from biplane TRUS plus MFI was highly consistent with postoperative pathological T staging. TRUS combined with MRI and serum CEA/CA199 had a greater value in the diagnosis of rectal cancer and a higher diagnostic rate than any examination alone.

Effects of Exercise on Motivational Outcomes in Rectal Cancer Patients During and After Neoadjuvant Chemoradiation: A Phase II Randomized Controlled Trial

OBJECTIVES

Understanding exercise motivation in rectal cancer patients during and after neoadjuvant chemoradiation therapy is important to improve adherence and achieve potential benefit. We report the motivational effects of exercise from the Exercise During and After Neoadjuvant Rectal Cancer Treatment trial.

DATA SOURCES

We randomized 36 rectal cancer patients to supervised high-intensity interval training during neoadjuvant chemoradiation therapy followed by unsupervised moderate-to-vigorous exercise after therapy, or usual care. Using the theory of planned behavior, we assessed motivation, perceived benefits/harms, and perceived barriers for exercise during and after therapy. Supervised exercise during neoadjuvant chemoradiation therapy was experienced as meaningfully (d≥0.33) more controllable (p=0.08, d=0.60), more enjoyable (p=0.25, d=0.45), and less difficult (p=0.45, d=-0.38) than anticipated. Unsupervised exercise after therapy was experienced as meaningfully more enjoyable (p=0.047, d=0.50) and less difficult (p=0.43, d=-0.36), but also less controllable (p=0.14, d=-0.80) than anticipated. Common self-reported benefits of exercise both during and after neoadjuvant chemoradiation therapy were cardiovascular endurance, physical functioning, and quality of life. Common self-reported harms were exacerbation of treatment side effects. Frequently reported barriers to exercise during therapy were side effects of treatment, whereas exercise barriers after therapy were lack of motivation and lingering side effects.

CONCLUSION

Exercise during and after therapy generally had positive effects on exercise motivation, however, perceived harms and barriers related to treatment side effects were identified.

IMPLICATIONS FOR NURSING PRACTICE

Nurses can help rectal cancer patients initiate and maintain exercise during and after neoadjuvant chemoradiation by discussing the potential benefits, harms, and barriers to exercise.

Nuclear Factor Erythroid 2-Related Factor 2/Kelch-Like ECH-Associated Protein 1 as a Predictor of Prognosis and Radiotherapy Resistance in Patients With Locally Advanced Rectal Cancer: A Prospective Analysis

BACKGROUND

The nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap1) signaling pathway is involved in the regulation of cellular responses to oxidative stress. Nrf2 acts as a cell protector from inflammation, cellular damage, and tumorigenesis, whereas Keap1 is a negative regulator of Nrf2. Dysregulation of the Nrf2/Keap1 pathway results in tumorigenesis and the active metabolism of tumor cells, leading to high resistance to radiotherapy. This study aimed to evaluate the predictive role of Nrf2 and Keap1 in the radiosensitivity and prognosis of locally advanced rectal cancer (LARC).

METHODS

In total, 90 patients with LARC underwent surgery after preoperative chemoradiotherapy (CRT). Endoscopic biopsies from the tumors were obtained before radiation, and the Nrf2 and Keap1 expressions were assessed by immunohistochemistry. The response to therapy was evaluated after surgery following CRT according to the pathologic tumor regression grade. The disease-free survival (DFS) and overall survival rates were also documented. The association between the Nrf2 and Keap1 immunoreactivity and the clinicopathological parameters was analyzed.

RESULTS

The overexpression of the nuclear Nrf2 before CRT showed a significant correlation with better DFS. The cytoplasmic Nrf2 expression was associated with more residual tumors after radiotherapy and a more unfavorable DFS, indicating lower radiosensitivity.

CONCLUSION

CRT is an important issue in LARC and is a major aspect of treatment. Thus, the Nrf2/Keap1 expression may be a potential predictor of preoperative therapeutic resistance. The Nrf2-Keap1 modulators that interact with each other may also be effectively applicable to CRT effect in LARC.

A multi-centre randomized controlled trial investigating Consolidation Chemotherapy with and without oxaliplatin in distal rectal cancer and Watch & Wait

BACKGROUND

Neoadjuvant chemoradiation(nCRT) has been considered the preferred initial treatment strategy for distal rectal cancer. Advantages of this approach include improved local control after radical surgery but also the opportunity for organ preserving strategies (Watch and Wait-WW). Consolidation chemotherapy(cCT) regimens using fluoropyrimidine-based with or without oxalipatin following nCRT have demonstrated to increase complete response and organ preservation rates among these patients. However, the benefit of adding oxaliplatin to cCT compared to fluoropirimidine alone regimens in terms of primary tumor response remains unclear. Since oxalipatin-treatment may be associated with considerable toxicity, it becomes imperative to understand the benefit of its incorporation into standard cCT regimens in terms of primary tumor response. The aim of the present trial is to compare the outcomes of 2 different cCT regimens following nCRT (fluoropyrimidine-alone versus fluoropyrimidine + oxaliplatin) for patients with distal rectal cancer.

METHODS

In this multi-centre study, patients with magnetic resonance-defined distal rectal tumors will be randomized on a 1:1 ratio to receive long-course chemoradiation (54 Gy) followed by cCT with fluoropyrimidine alone versus fluoropyrimidine + oxaliplatin. Magnetic resonance(MR) will be analyzed centrally prior to patient inclusion and randomization. mrT2-3N0-1 tumor located no more than 1 cm above the anorectal ring determined by sagittal views on MR will be eligible for the study. Tumor response will be assessed after 12 weeks from radiotherapy(RT) completion. Patients with clinical complete response (clinical, endoscopic and radiological) may be enrolled in an organ-preservation program(WW). The primary endpoint of this trial is decision to organ-preservation surveillance (WW) at 18 weeks from RT completion. Secondary endpoints are 3-year surgery-free survival, TME-free survival, distant metastases-free survival, local regrowth-free survival and colostomy-free survival.

DISCUSSION

Long-course nCRT with cCT is associated with improved complete response rates and may be a very attractive alternative to increase the chances for organ-preservation strategies. Fluoropyrimidine-based cCT with or without oxaliplatin has never been investigated in the setting of a randomized trial to compare clinical response rates and the possibility of organ-preservation. The outcomes of this study may significantly impact clinical practice of patients with distal rectal cancer interested in organ-preservation.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov NCT05000697; registered on August 11^th, 2021.

Patterns of Care and Outcomes of Rectal Cancer Patients from the Iowa Cancer Registry: Role of Hospital Volume and Tumor Location

BACKGROUND

Centralization of rectal cancer surgery has been associated with high-quality oncologic care. However, several patient, disease and system-related factors can impact where patients receive care. We hypothesized that patients with low rectal tumors would undergo treatment at high-volume centers and would be more likely to receive guideline-based multidisciplinary treatment.

METHODS

Adults who underwent proctectomy for stage II/III rectal cancer were included from the Iowa Cancer Registry and supplemented with tumor location data. Multinomial logistic regression was employed to analyze factors associated with receiving care in high-volume hospital, while logistic regression for those associated with ≥ 12 lymph node yield, pre-operative chemoradiation and sphincter-preserving surgery.

RESULTS

Of 414 patients, 38%, 39%, and 22% had low, mid, and high rectal cancers, respectively. Thirty-two percent were > 65 years, 38% female, and 68% had stage III tumors. Older age and rural residence, but not tumor location, were associated with surgical treatment in low-volume hospitals. Higher tumor location, high-volume, and NCI-designated hospitals had higher nodal yield (≥ 12). Hospital-volume was not associated with neoadjuvant chemoradiation rates or circumferential resection margin status. Sphincter-sparing surgery was independently associated with high tumor location, female sex, and stage III cancer, but not hospital volume.

CONCLUSIONS

Low tumor location was not associated with care in high-volume hospitals. High-volume and NCI-designated hospitals had higher nodal yields, but not significantly higher neoadjuvant chemoradiation, negative circumferential margin, or sphincter preservation rates. Therefore, providing educational/quality improvement support in lower volume centers may be more pragmatic than attempting to centralize rectal cancer care among high-volume centers.

A type I interferon footprint in pre-operative biopsies is an independent biomarker that in combination with CD8+ T cell quantification can improve the prediction of response to neoadjuvant treatment of rectal adenocarcinoma

Tailored treatment for patients with rectal cancer requires clinically available markers to predict their response to neoadjuvant treatment. The quantity of tumor-infiltrating lymphocytes (TILs) in pre-operative tumor biopsies has been suggested to predict a favorable response, but opposing results exist. A biopsy-adapted Immunoscore (ISB) based on TILs has recently emerged as a promising predictor of tumor regression and prognosis in (colo)rectal cancer. We aimed to refine the ISB for prediction of response using multiplex immunofluorescence (mIF) on pre-operative rectal cancer biopsies. We combined the distribution and density of conventional T cell subsets and γδT cells with a type I Interferon (IFN)-driven response assessed using Myxovirus resistance protein A (MxA) expression. We found that pathological complete response (pCR) following neoadjuvant treatment was associated with type I IFN. Stratification of patients according to the density of CD8+ in the entire tumor tissue and MxA+ cells in tumor stroma, where equal weight was assigned to both parameters, resulted in improved predictive quality compared to the ISB. This novel stratification approach using these two independent parameters in pre-operative biopsies could potentially aid in identifying patients with a good chance of achieving a pCR following neoadjuvant treatment.

Diagnostic pitfalls: a case of prostate cancer and rectal cancer accompanied by prostate cancer invasion of the rectum

INTRODUCTION

Case of double primary cancer of the prostate and rectum is rare, prostate cancer involving the postoperative intestinal anastomotic mucosal tissue is even rarer.

CASE PRESENTATION

We report a case of rectal cancer discovered 1 year after a diagnosis of prostate cancer and a tumour in the postoperative anastomotic intestinal mucosal tissue involving prostatic adenocarcinoma at 1 year after the diagnosis of rectal cancer. Due to the poor differentiation of both prostate and rectal cancers, there are some pitfalls in the diagnosis of intestinal mucosal lesions at an anastomosis. The lack of an accurate diagnosis of a tumour in anastomosis intestinal mucosal tissue will affect treatment and patient survival.

CONCLUSIONS

The pathologists should have a detailed understanding of the patient's medical history and carefully observe the histopathological morphology and, if necessary, immunohistochemistry or other techniques should be used to assist in the pathological diagnosis and avoid both misdiagnosis and missed diagnosis.

Symptom Occurrence, Frequency, and Severity During Acute Colorectal Cancer Survivorship

OBJECTIVES

To examine colorectal cancer (CRC) survivors' symptom characteristics (occurrence, frequency, and severity) during acute cancer survivorship.

PARTICIPANTS & SETTING

A cross-sectional study of 117 CRC survivors was conducted at a National Cancer Institute-designated cancer center in South Florida.

METHODS & VARIABLES

Symptom characteristics were assessed by the Therapy-Related Symptom Checklist. Participants completed a 25-item demographic questionnaire. Mann-Whitney U and Kruskal-Wallis H tests assessed between-group differences based on sex, age, education, and months since diagnosis. Exploratory factor analysis was performed to identify preliminary symptom clusters.

RESULTS

117 CRC survivors completed the study (age range = 21-88 years, 56% male, and 79% stage IV). Common symptoms included peripheral neuropathy, fatigue/feeling sluggish, and skin changes. Significance was found between months since diagnosis and number of symptoms (p = 0.03), suggesting that symptoms accumulate with time. Chemotherapy (85%) was the most common treatment type, and exploratory factor analysis identified two chemotherapy-related symptom clusters.

IMPLICATIONS FOR NURSING

Nurses are poised to identify, prevent, and promote self-management skills to reduce symptoms.

Population pharmacokinetic analyses of regorafenib and capecitabine in patients with locally advanced rectal cancer (SAKK 41/16 RECAP)

AIM

Locally advanced rectal cancer (LARC) is an area of unmet medical need with one third of patients dying from their disease. With response to neoadjuvant chemo-radiotherapy being a major prognostic factor, trial SAKK 41/16 assessed potential benefits of adding regorafenib to capecitabine-amplified neoadjuvant radiotherapy in LARC patients.

METHODS

Patients received regorafenib at three dose levels (40/80/120 mg once daily) combined with capecitabine 825 mg/m² bidaily and local radiotherapy. We developed population pharmacokinetic models from plasma concentrations of capecitabine and its metabolites 5'-deoxy-5-fluorocytidine and 5'-deoxy-5-fluorouridine as well as regorafenib and its metabolites M-2 and M-5 as implemented into SAKK 41/16 to assess potential drug-drug interactions (DDI). After establishing parent-metabolite base models, drug exposure parameters were tested as covariates within the respective models to investigate for potential DDI. Simulation analyses were conducted to quantify their impact.

RESULTS

Plasma concentrations of capecitabine, regorafenib and metabolites were characterized by one- and two compartment models and absorption was described by parallel first- and zero-order processes and transit compartments, respectively. Apparent capecitabine clearance was 286 L/h (relative standard error [RSE] 14.9%, interindividual variability [IIV] 40.1%) and was reduced by regorafenib cumulative area under the plasma-concentration curve (median reduction of 45.6%) as exponential covariate (estimate -4.10×10^-4 , RSE 17.8%). Apparent regorafenib clearance was 1.94 L/h (RSE 12.1%, IIV 38.1%). Simulation analyses revealed significantly negative associations between capecitabine clearance and regorafenib exposure.

CONCLUSIONS

This work informs the clinical development of regorafenib and capecitabine combination treatment and underlines the importance to study potential DDI with new anticancer drug combinations.

Incidental Polyp on Colectomy Specimen is Linked with Higher Odds of Polyp on Interval Colonoscopy

BACKGROUND

Incidentally found polyps on surgical pathology after colectomy is an underreported phenomenon, and management guidelines are lacking. Elucidation of the significance of incidental polyps is needed to determine if post-operative endoscopic surveillance modification is warranted. We sought to determine the relationship between incidental polyp on colectomy specimen and findings on post-operative colonoscopy.

MATERIALS AND METHODS

A multi-institutional retrospective review was performed on patients that underwent colorectal resection from 2018-2019. Surgical pathology was reviewed for polyps and assigned as expected or incidental based on pre-operative colonoscopy. If performed, post-operative colonoscopy was reviewed for new lesion identification. The odds of detecting new lesion on post-operative colonoscopy was compared between cases with incidental polyp on surgical specimen and patients without incidental findings.

RESULTS

In 243 colorectal resections, incidental polyps were identified in 55 cases(22.6%). Post-operative colonoscopy was completed in 65 cases(26.7%) with new polyp detected in 24 cases(9.88%). Of those, 10 had an incidental polyp previously identified on surgical specimen while 14 did not. The presence of incidental surgical specimen polyp was associated with a greater than two-fold higher odds of detecting new polyp on post-operative colonoscopy(odds-ratio 2.76, 95% confidence interval 1.15-6.63;P = 0.023).

CONCLUSION

This analysis revealed a high frequency of incidental polyps on surgical specimens with an increased rate of newly found lesions on post-operative colonoscopy. Incidental polyps may be a risk factor for other missed lesions still within the patient. Therefore, providers should consider surveillance interval modification on an individual basis in the setting of incidental surgical specimen polyps.

Impact of Androgens on Sexual Function in Women With Rectal Cancer - A Prospective Cohort Study

BACKGROUND

Women treated for rectal cancer are at risk of sexual dysfunction and impaired ovarian androgen production.

AIM

To investigate a possible association between serum levels of endogenous androgens and sexual function in women with rectal cancer.

METHODS

Women diagnosed with stage I-III rectal cancer were consecutively included and prospectively followed with the Female Sexual Function Index (FSFI) questionnaire from baseline to 2 years postoperatively and blood samples for hormone analyses, baseline to 1 year. Androgens were measured with liquid chromatography-mass spectrometry and electrochemiluminescence. The associations between the 4 measured androgens (testosterone, free testosterone, androstenedione, and dehydroepiandrosterone sulphate) and sexual function were assessed with generalized least squares random effects regression analysis in sexually active women.

OUTCOMES

The primary outcome measure was the mean change observed in the FSFI total score when the serum androgen levels changed with one unit. Secondary outcomes were the corresponding mean changes in the FSFI domain scores: sexual desire, arousal, lubrication, orgasm, satisfaction, and pain/discomfort.

RESULTS

In the 99 participants, the median FSFI total score decreased from 21.9 (range 2.0 - 36.0) to 16.4 (3.5 - 34.5) and 11.5 (2.0 to 34.8) at 1 and 2-years follow-up. After adjustment for age, partner, psychological well-being, preoperative (chemo)radiotherapy, and surgery, total testosterone and androstenedione were significantly associated with FSFI total score (β-coefficients 3.45 (95% CI 0.92 - 5.97) and 1.39 (0.46 - 2.33) respectively). Testosterone was significantly associated with the FSFI-domains lubrication and orgasm, free testosterone with lubrication, androstenedione with all domains except desire and satisfaction, and dehydroepiandrosterone sulphate with none of the domains.

STRENGTHS AND LIMITATIONS

This is the first study investigating whether androgen levels are of importance for the impaired sexual function seen in women following rectal cancer treatment. The prospective design allows for repeated measures and the use of the FSFI for comparisons across studies. No laboratory data were collected at the 2-year follow-up, and the missing data could have further clarified the studied associations.

CONCLUSION AND CLINICAL IMPLICATION

Testosterone and androstenedione were associated with sexual function in female rectal cancer patients. The results are of interest for future intervention studies and contribute to the understanding of sexual problems, which is an essential component of the rehabilitation process in pelvic cancer survivors. Svanström Röjvall A, Buchli C, Flöter Rådestad A, et al. Impact of Androgens on Sexual Function in Women With Rectal Cancer - A Prospective Cohort Study. J Sex Med 2021;18:1374-1382.

The Efficacy of Transanal Total Mesorectal Excision: a Preliminary Vietnamese Report

Introduction:

The e physical anatomical characteristics of Vietnamese people are similar to those of other East Asian populations, with a deep and narrow pelvis but an average body mass index (BMI) among patients at the advanced stage of rectal cancer.

Aim:

This study aimed to prospectively evaluate the short-term outcomes of transanal total mesorectal excision (TaTME) for rectal cancer treatment in a Vietnamese population.

Methods:

A total of 64 patients who underwent TaTME were included in this study. The pelvic anatomical parameters, BMI, operative morbidities, macroscopic qualities of the mesorectal specimens, circumferential resection margins, and anal sphincter functional data were collected. The method popularized by Quirke and Kirwan’s classification were used to assess to quality of the mesorectal specimens and the sphincter function, respectively. Statistical analysis was performed using SPSS 20.0.

Results:

The mean age and BMI of the patients were 66.4 years and 20.5 kg/m2, respectively. Most patients had narrow pelvises, with mean transverse pelvic outlet diameters of 10.12 ±1.85 cm, for males, and 10.43 ± 1.32 cm, for females, and pelvic depths of 12.36 ±2.03 cm, for males, and 11.73 ±1.12 cm, for females. The mean tumor size was 5.17 ±1.62 cm. Among the mesorectal specimens, 82.8% were complete and 14.1% were nearly complete. Disease-free survival and overall survival rates were 98.2% and 100%, respectively. Sphincter functions at 12 months post-operation were rated as 30.8% Kirwan I, 42.3% Kirwan II, and 26.9% Kirwan III.

Conclusion:

TaTME surgery represents a safe and suitable option among Vietnamese patients with narrow and deep pelvises and advanced rectal tumors in the middle third and lower third of the rectum.

Efficacy of conversion therapy on initially unresectable locally advanced rectal cancer

Background and purpose: Research on the efficacy of conversion therapy for initially unresectable mid-low rectal cancer (IURC) remained limited. This study aimed to assess the efficacy and safety of the conversion regimen for IURC and analyze the long-term outcomes of these patients.

Methods: We retrospectively analyzed the data of clinically diagnosed IURC patients who received conversion therapy between October 2010 and April 2017. The conversion therapy consisted of long-term radiation, concurrent chemotherapy, delayed surgery and consolidation chemotherapy. The primary end point was the rate of R0 resection, and other short- and long-term outcomes were analyzed.

Results: Sixty-one patients were enrolled in this study. After conversion therapy, 51 (83.6%) patients received R0 resection. The rates of pathologic complete response and downstaging were 16.4% and 62.3%, respectively. The rate of grade 3-4 chemoradiotherapy-related toxicity events was 13.1%. The overall survival at 3 years was 75.4% in all patients, and the disease-free survival at 3 years was 72.5% in patients who received R0 resection.

Conclusion: The conversion regimen showed a high conversion resection rate and good survival outcomes in IURC patients, and might benefit the patients if recommended in clinical practice.

community centers: A propensity-matched analysis of the National Cancer Database

BACKGROUND

Little is known regarding the impact of hospital academic status on outcomes following rectal cancer surgery. We compare these outcomes for nonmetastatic rectal adenocarcinoma at academic versus community institutions.

METHODS

The National Cancer Database (2010-2016) was queried for patients with nonmetastatic rectal adenocarcinoma who underwent resection. Propensity score matching was performed across facility cohorts to balance confounding covariates. Kaplan-Meier estimation and Cox-proportional hazards regression were used to analyze survival, other short and long-term outcomes were analyzed by way of logistic regression.

RESULTS

After matching, 15,096 patients were included per cohort. Academic centers were associated with significantly decreased odds of conversion and positive margins with significantly increased odds of ≥12 regional nodes examined. Academic programs also had decreased odds of 30 and 90-day mortality and decreased 5-year mortality hazard. After matching for facility volume, no significant differences in outcomes between centers was seen.

CONCLUSIONS

No difference between academic and community centers in outcomes following surgery for non-metastatic rectal cancer was seen after matching for facility procedural volume.

Integrated slice-specific dynamic shimming diffusion weighted imaging (DWI) for rectal Cancer detection and characterization

PURPOSE

To compare integrated slice-specific dynamic shimming (iShim) diffusion weighted imaging (DWI) and single-shot echo-planar imaging (SS-EPI) DWI in image quality and pathological characterization of rectal cancer.

MATERIALS AND METHODS

A total of 193 consecutive rectal tumor patients were enrolled for retrospective analysis. Among them, 101 patients underwent iShim-DWI (b = 0, 800, and 1600 s/mm²) and 92 patients underwent SS-EPI-DWI (b = 0, and 1000 s/mm²). Qualitative analyses of both DWI techniques was performed by two independent readers; including adequate fat suppression, the presence of artifacts and image quality. Quantitative analysis was performed by calculating standard deviation (SD) of the gluteus maximus, signal intensity (SI) of lesion and residual normal rectal wall, apparent diffusion coefficient (ADC) values (generated by b values of 0, 800 and 1600 s/mm² for iShim-DWI, and by b values of 0 and 1000 s/mm² for SS-EPI-DWI) and image quality parameters, such as signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of primary rectal tumor. For the primary rectal cancer, two pathological groups were divided according to pathological results: Group 1 (well-differentiated) and Group 2 (poorly differentiated). Statistical analyses were performed with p < 0.05 as significant difference.

RESULTS

Compared with SS-EPI-DWI, significantly higher scores of image quality were obtained in iShim-DWI cases (P < 0.001). The SD_background was significantly reduced on b = 1600 s/mm² images and ADC maps of iShim-DWI. Both SNR and CNR of b = 800 s/mm² and b = 1600 s/mm² images in iShim-DWI were higher than those of b = 1000 s/mm² images in SS-EPI-DWI. In primary rectal cancer of iShim-DWI cohort, SI_lesion was significantly higher than SI_rectum in both b = 800 and 1600 s/mm² images. ADC values were significantly lower in Group 2 (0.732 ± 0.08) × 10^- 3 mm²/s) than those in Group 1 ((0.912 ± 0.21) × 10^- 3 mm²/s). ROC analyses showed significance of ADC values and SI_lesion between the two groups.

CONCLUSION

iShim-DWI with b values of 0, 800 and 1600 s/mm² is a promising technique of high image quality in rectal tumor imaging, and has potential ability to differentiate rectal cancer from normal wall and predicting pathological characterization.

Baseline liver steatosis has no impact on liver metastases and overall survival in rectal cancer patients

Background

The liver is one of the most frequent sites of metastases in rectal cancer. This study aimed to evaluate how the development of synchronous or metachronous liver metastasis and overall survival are impacted by baseline liver steatosis and chemotherapy-induced liver damage in rectal cancer patients.

Methods

Patients diagnosed with stage II to IV rectal cancer between 2010 and 2016 in our province with suitable baseline CT scan were included. Data on cancer diagnosis, staging, therapy, outcomes and liver function were collected. CT scans were retrospectively reviewed to assess baseline steatosis (liver density < 48 HU and/or liver-to-spleen ratio < 1.1). Among patients without baseline steatosis and treated with neoadjuvant chemotherapy, chemotherapy-induced liver damage was defined as steatosis appearance, ≥ 10% liver volume increase, or significant increase in liver function tests.

Results

We included 283 stage II to IV rectal cancer patients with suitable CT scan (41% females; mean age 68 ± 14 years). Steatosis was present at baseline in 90 (31.8%) patients, synchronous liver metastasis in 42 (15%) patients and metachronous liver metastasis in 26 (11%); 152 (54%) deaths were registered. The prevalence of synchronous liver metastasis was higher in patients with steatosis (19% vs 13%), while the incidence of metachronous liver metastasis was similar. After correcting for age, sex, stage, and year of diagnosis, steatosis was not associated with metachronous liver metastasis nor with overall survival. In a small analysis of 63 patients without baseline steatosis and treated with neoadjuvant chemotherapy, chemotherapy-induced liver damage was associated with higher incidence of metachronous liver metastasis and worse survival, results which need to be confirmed by larger studies.

Conclusions

Our data suggest that rectal cancer patients with steatosis had a similar occurrence of metastases during follow-up, even if the burden of liver metastases at diagnosis was slightly higher, compatible with chance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07980-9.

The "Reverse Air-Leak Test" : A New Technique for the Assessment of Low Colorectal Anastomosis

Background

Anastomotic leakage is a fearsome complication in rectal surgery. Surgeons perform the classic air-leak test, although its real effectiveness is still debated. The aim of this study was to describe a personal technique of reverse air leak test in which low colorectal anastomosis were assessed transanally through the intra-rectal irrigation of a few mL of saline solution.

Methods

From October 2014 to November 2019 eleven patients with low rectal cancer (Type 1 in Roullier classification) were included in this study. At the beginning of the procedure, a circular anal dilator (CAD) was inserted into the anus. A side-to-end colorectal anastomosis was performed. A few mL of saline solution were injected into the rectum and the entire anastomotic line was directly explored. The appearance of bubbles was considered as an anastomotic defect and repaired with an interrupted suture. A fluorescence angiography after intravenous injection of Indocyanine green was performed in order to evaluate the perfusion of the anastomosis.

Results

In 4 cases (36.3%) the reverse air-leak test was positive. The defect was repaired and a confirmation test was performed. In all patients, near-infrared evaluation showed not perfusion defect (grade 0) in low colorectal anastomosis. No post-operative fistula was detected in cohort study. A protective stoma was performed in 10 patients. At 90-days there were no complications and stoma closure was performed as planned.

Conclusion

The reverse air-leak test is a simple, feasible and effective procedure to identify anastomotic leak in low colorectal anastomoses.

Gender differences in stage at diagnosis and preoperative radiotherapy in patients with rectal cancer

Background

Few studies have examined gender differences in the clinical management of rectal cancer. We examine differences in stage at diagnosis and preoperative radiotherapy in rectal cancer patients.

Methods

A prospective cohort study was conducted in 22 hospitals in Spain including 770 patients undergoing surgery for rectal cancer. Study outcomes were disseminated disease at diagnosis and receiving preoperative radiotherapy. Age, comorbidity, referral from a screening program, diagnostic delay, distance from the anal verge, and tumor depth were considered as factors that might explain gender differences in these outcomes.

Results

Women were more likely to be diagnosed with disseminated disease among those referred from screening (odds ratio, confidence interval 95% (OR, CI = 7.2, 0.9–55.8) and among those with a diagnostic delay greater than 3 months (OR, CI = 5.1, 1.2–21.6). Women were less likely to receive preoperative radiotherapy if they were younger than 65 years of age (OR, CI = 0.6, 0.3–1.0) and if their tumors were cT3 or cT4 (OR, CI = 0.5, 0.4–0.7).

Conclusions

The gender-specific sensitivity of rectal cancer screening tests, gender differences in referrals and clinical reasons for not prescribing preoperative radiotherapy in women should be further examined. If these gender differences are not clinically justifiable, their elimination might enhance survival.

Genomic variation as a marker of response to neoadjuvant therapy in locally advanced rectal cancer

There is variation in the responsiveness of locally advanced rectal cancer to neoadjuvant chemoradiation, from complete response to total resistance. This study compared genetic variation in rectal cancer patients who had a complete response to chemoradiation versus poor response, using tumor tissue samples sequenced with genomics analysis software. Rectal cancer patients treated with chemoradiation and proctectomy June 2006-March 2017 were grouped based on response to chemoradiation: those with no residual tumor after surgery (CR, complete responders, AJCC-CPR tumor grade 0, n = 8), and those with poor response (PR, AJCC-CPR tumor grade two or three on surgical resection, n = 8). We identified 195 variants in 83 genes in tissue specimens implicated in colorectal cancer biopathways. PR patients showed mutations in four genes not mutated in complete responders: KDM6A, ABL1, DAXX-ZBTB22, and KRAS. Ten genes were mutated only in the CR group, including ARID1A, PMS2, JAK1, CREBBP, MTOR, RB1, PRKAR1A, FBXW7, ATM C11orf65, and KMT2D, with specific discriminating variants noted in DMNT3A, KDM6A, MTOR, APC, and TP53. Although conclusions may be limited by small sample size in this pilot study, we identified multiple genetic variations in tumor DNA from rectal cancer patients who are poor responders to neoadjuvant chemoradiation, compared to complete responders.

Improving quality of care and clinical outcomes for rectal cancer through clinical audits in a multicentre cancer care organisation

Introduction

Colorectal cancer treatment requires a complex, multidisciplinary approach. Because of the potential variability, monitoring through clinical audits is advisable. This study assesses the effects of a quality improvement action plan in patients with locally advanced rectal cancer and treated with radiotherapy.

Methods

Comparative, multicentre study in two cohorts of 120 patients each, selected randomly from patients diagnosed with rectal cancer who had initiated radiotherapy with a curative intent. Based on the results from a baseline clinical audit in 2013, a quality improvement action plan was designed and implemented; a second audit in 2017 evaluated its impact.

Results

Standardised information was present on 77.5% of the magnetic resonance imaging (MRI) staging reports. Treatment strategies were similar in all three study centres. Of the patients whose treatment was interrupted, just 9.7% received a compensation dose. There was an increase in MRI re-staging from 32.5 to 61.5%, and a significant decrease in unreported circumferential resection margins following neoadjuvant therapy (ypCRM), from 34.5 to 5.6% (p <  0.001).

Conclusions

The comparison between two clinical audits showed improvements in neoadjuvant radiotherapy in rectal cancer patients. Some indicators reveal areas in need of additional efforts, for example to reduce the overall treatment time.

Current controversy, confusion, and imprecision in the use and interpretation of rectal MRI

There has been a rapid increase in the utilization of MRI in rectal cancer staging in the USA essentially replacing endorectal ultrasound and mimicking the trend in Europe seen in the 1990s and 2000s. Accompanying this trend, there is a demand, and recognized need, for greater precision and clarification of confusing, misunderstood and poorly understood concepts, facts, statements and nomenclature regarding rectal cancer and the use of pelvic MRI for diagnosis. As such, this Review, part evidence-based and part expert opinion, will attempt to elucidate and clarify several concepts the authors have encountered in 25 years of imaging rectal cancer, focusing on MRI.

Current controversy, confusion, and imprecision in the use and interpretation of rectal MRI

There has been a rapid increase in the utilization of MRI in rectal cancer staging in the USA essentially replacing endorectal ultrasound and mimicking the trend in Europe seen in the 1990s and 2000s. Accompanying this trend, there is a demand, and recognized need, for greater precision and clarification of confusing, misunderstood and poorly understood concepts, facts, statements and nomenclature regarding rectal cancer and the use of pelvic MRI for diagnosis. As such, this Review, part evidence-based and part expert opinion, will attempt to elucidate and clarify several concepts the authors have encountered in 25 years of imaging rectal cancer, focusing on MRI.

Impact of PET/CT for Restaging Patients With Locally Advanced Rectal Cancer After Neoadjuvant Chemoradiation

BACKGROUND

A major challenge in identifying candidates for nonoperative management of locally advanced rectal cancer is predicting pathologic complete response (pCR) following chemoradiation. We evaluated pre- and post-CRT PET-CT imaging to predict pCR and prognosis in this set of patients undergoing resection after neoadjuvant therapy.

METHODS

We retrospectively identified patients from 2002 to 2015 with locally advanced rectal cancer who underwent CRT, pre- and post-CRT PET-CT imaging, and resection. Univariate and multivariate analysis was performed and receiver operating characteristic (ROC) curves were generated to evaluate the association of PET-CT characteristics with pCR and survival. ROC curves were generated to define optimal cutoff points for predictive PET-CT characteristics.

RESULTS

125 patients were included. pCR rate was 28%, and follow-up was 48 mo. On multivariable analysis, patients who had a pCR had lower median post-CRT maximal standardized uptake value (SUV_max) (3.2 versus 5.2, P = 0.009) and higher median %SUV decrease (72 versus 58%, P = 0.009). ROC curves were generated for %SUV_max decrease (AUC = 0.70) and post-CRT SUV (AUC = 0.69). Post-CRT SUV_max <4.3 and %SUV_max decrease of >66% were equally predictive of pCR with a sensitivity of 65%, specificity of 72%, PPV of 44%, and NPV of 86%. Median 5-y overall and relapse-free survival were improved for patients with post-CRT SUV <4.3 (OS: 86 versus 66%, P = 0.01; RFS: 75 versus 52%, P = 0.01) or %SUV decrease of >66% (OS, 82 versus 66%, P = 0.05; RFS, 75 versus 54%, P = 0.01).

CONCLUSIONS

PET/CT may be useful in identifying patients who did not achieve pCR, as well as overall survival in patients undergoing CRT for rectal cancer. Patients with a post-CRT SUV of >4.3 should be considered for operative management, as an estimated 86% of these patients will not have a pCR.

Strategy to avoid local recurrence in patients with locally advanced rectal cancer

Background

To clarify the short- and long-term outcomes of radical surgery after neoadjuvant chemoradiotherapy (NCRT) with TS-1 and irinotecan, which enhances radiosensitivity, in patients with locally advanced rectal cancer.

Methods

The study group comprised 105 patients with locally advanced rectal cancer who received NCRT followed by radical surgery. NCRT consisted of pelvic radiotherapy (45 Gy in 25 fractions over a period of 5 weeks), S-1 (80 mg/m²) given concurrently for 25 days, and irinotecan (60 mg/m²), given once a week as a continuous intravenous infusion. Radical surgery was performed 8 weeks after treatment.

Results

A pathological complete response was confirmed in 23.8%. The 5-year recurrence-free survival rate was 79.3%, and the 5-year overall survival rate was 87.1%. Multivariate analysis showed that the following 4 variables were independent predictors of recurrence-free survival: Sex (male: p = 0.0172), Pre-treatment tumor diameter (< 40 mm: p = 0.0223), Histopathological treatment response (grade 0,1: p = 0.0169), and ypN (ypN1: p = 0.1995; ypN2: p = 0.0007). Only ypN was an independent predictor of overall survival (ypN1: p = 0.0009; ypN2: p = 0.0012).

Conclusions

Our treatment strategy combining TS-1 with irinotecan to increase radiosensitivity had a high response rate.

Elevated platelet count is a negative predictive and prognostic marker in locally advanced rectal cancer undergoing neoadjuvant chemoradiation: a retrospective multi-institutional study on 965 patients

BACKGROUND

In patients with locally advanced rectal cancer treated by neoadjuvant chemoradiation, pathological complete response in the surgical specimen is associated with favourable long-term oncologic outcome. Based on this observation, nonoperative management is being explored in the subset of patients with clinical complete response. Whereas, patients with poor response have a high risk of local and distant recurrence, and appear to receive no benefit from standard neoadjuvant chemoradiation. Therefore, in order to develop alternative treatment strategies for non responding patients, predictive and prognostic factors are highly needed. Accumulating clinical observations indicate that elevated platelet count is associated with poor outcome in different type of tumors. In this study we investigated the predictive and prognostic impact of elevated platelet count on pathological response and long-term oncologic outcome in patients with locally advanced rectal cancer undergoing neoadjuvant chemoradiation.

METHODS

A total of 965 patients were selected from prospectively maintained databases of seven Centers within the SICO Colorectal Cancer Network. Patients were divided into two groups based on a pre-neoadjuvant chemoradiation platelet count cut-off value of 300 × 10⁹/L identified by receiver operating characteristic curve considering complete pathological response as the outcome.

RESULTS

Complete pathological response rate was lower in patients with elevated platelet count (12.8% vs. 22.1%, p = 0.001). Mean follow-up was 50.1 months. Comparing patients with elevated platelet count with patients with not elevated platelet count, 5-year overall survival was 69.5% vs.76.5% (p = 0.016), and 5-year disease free survival was 63.0% vs. 68.9% (p = 0.019). Local recurrence rate was higher in patients with elevated platelet count (11.1% vs. 5.3%, p = 0.001), as higher was the occurrence of distant metastasis (23.9% vs. 16.4%, p = 0.007). At multivariate analysis of potential prognostic factors EPC was independently associated with worse overall survival (HR 1.40, 95% CI 1.06-1.86), and disease free survival (HR 1.37, 95% CI 1.07-1.76).

CONCLUSIONS

In locally advanced rectal cancer elevated platelet count before neoadjuvant chemoradiation is a negative predictive and prognostic factor which might help to identify subsets of patients with more aggressive tumors to be proposed for alternative therapeutic strategies.

Oncological outcomes of abdominoperineal resection for the treatment of low rectal cancer: A retrospective review of a single UK tertiary centre experience

Background

The use of abdominoperineal resection (APR) in the management of low rectal cancer has received criticism over high rates of incomplete resection due to tumour involvement at the circumferential resection margin. Extralevator abdominoperineal resection has been advocated as a means of improving complete resection. However, Extralevator abdominoperineal resection can result in increased cost, morbidity and reduced quality of life.

This study aims to assess the histological features and long-term outcomes of patients undergoing standard abdominoperineal resection and discusses the potential role of Extralevator abdominoperineal resection in this cohort.

Method

A retrospective review of a prospectively maintained database of rectal cancer patients at a single centre. Patients undergoing standard APR were included from 01/06/2007 to 31/05/2012 to allow a minimum 2-year follow-up. Data was collected on age, gender, co-morbidity, pre-operative stage, neo-adjuvant therapy, histology, recurrence and mortality.

Results

Seventy patients were identified (45 (64%) male, median age 67; (range 36–85)). 12 (17.1%) patients had a positive circumferential resection margin; 4 (6.1%) tumours were located anteriorly, 8 (11%) were located posteriorly or laterally and may potentially have been completely resected with extralevator abdomino-perineal resection, Number-needed to treat = 9. Positive circumferential resection margin was more common in advanced tumours (p < 0.001). Local recurrence was more common with positive circumferential resection margins (16.7% Vs 0%, p = 0.027), with no statistically significant difference in 5-year survival, although there was a tendency towards worse survival in these patients.

Conclusion

Positive circumferential resection margin following APR resulted in significantly increased local recurrence with a trend towards poorer survival outcomes. Extralevator abdomino-perineal resection may have benefited some of these patients with locally advanced tumours and postero-lateral recurrences. However, this has to be balanced against exposing patients to increased risk of adverse events. We would recommend selective use of Extralevator abdominoperineal resection for locally advanced and node-positive tumours although further studies to help refine selection criteria are required with long-term follow-up.

•

A single high-volume Centre, retrospective study.

•

5 years data of low rectal cancer patients undergoing standard abdomino-perineal resection of rectum (APR).

•

Positive CRM is associated with increased local recurrence.

•

This study reports that careful selection of patients for ELAPE is vital.

•

The numbers needed to treat are 9.

•

ELAPE is advisable in locally advanced and postero-lateral low rectal cancers.

Session 2: Are we ready for primary chemotherapy in rectal cancer: who, when, why?

The potential of preoperative chemotherapy in rectal cancer is the subject of investigation in a number of global randomized trials. In this overview and expert discussion, Professor Cervantes summarizes the findings of numerous Phase II trials testing neoadjuvant chemotherapy. The crucial points in the next phase of trials include: patient selection, whether radiotherapy can be omitted altogether and whether chemotherapy can be used to augment the initial response to chemoradiotherapy. Finally, with the emergence of Magnetic Resonance Tumour Regression Grade a reliable method for assessing response after initial chemoradiotherapy, we ask if this can be used to drive the use of further selective chemotherapy to augment response.

Long-Term Outcome of Oxaliplatin and Capecitabine (XELOX) Concomitant with Neoadjuvant Radiotherapy and Extended to the Resting Period in High Risk Locally Advanced Rectal Cancer

Purpose: This study aimed at investigating the long-term outcomes of oxaliplatin and capecitabine (XELOX) administered concurrently with preoperative radiation and extended to the resting period in patients with high-risk locally advanced rectal cancer (LARC).

Methods: From January 2010 to December 2013, 45 patients were recruited. Study treatment consisted two cycles of XELOX regimen concomitant with preoperative radiation and then followed by an additional cycle of XELOX regimen between completion of neoadjuvant radiotherapy and surgery. Disease-free survival (DFS) time and overall survival (OS) time were analyzed.

Results: The median follow-up was 51 months. Twelve (26.7%) patients developed local recurrence or distant metastasis, including 10 (22.2%) patients developing distant metastasis only, 1 (2.2%) patient local recurrence only, and 1 (2.2%) patient both local recurrence and distant metastasis. The estimated 3-year DFS and OS was 75.5% (95% CI, 63.0%-88.0%) and 88.6% (95% CI, 98.0%-79.2%), respectively. Receiving adjuvant chemotherapy was a significant predictor for DFS, with hazard ratio 0.24 (95% CI: 0.08-0.74).

Conclusion: This intensified strategy with oxaliplatin and capecitabine (XELOX) administered concomitantly with neoadjuvant radiotherapy and then extended to the resting period in high-risk LARC patients is efficient. The long-term outcome is promising. Further study of this strategy is warranted.

Association Between Coffee Intake After Diagnosis of Colorectal Cancer and Reduced Mortality

BACKGROUND & AIMS

Few studies have examined the association between coffee intake and survival after diagnosis of colorectal cancer (CRC). We performed a prospective study to investigate the association between coffee intake after a diagnosis of CRC and mortality.

METHODS

We collected data from the Nurses' Health Study (1984-2012) and Health Professionals Follow-up Study (1986-2012), following 1599 patients diagnosed with stage 1, 2, or 3 CRC. CRC was reported on questionnaires and ascertained by review of medical records and pathology reports; intake of food and beverages was determined from responses to semi-quantitative food frequency questionnaires. Participants were asked how often during the previous year that they consumed coffee, with 1 cup as the standard portion size. The first questionnaire response collected at least 6 months but not more than 4 years after diagnosis was used for assessment of post-diagnostic intake (median time from diagnosis to the dietary assessment, 2.2 years). The last semi-quantitative food frequency questionnaire prior to diagnosis was used to assess pre-diagnostic dietary intake.

RESULTS

During a median of 7.8 years of follow-up, we documented 803 deaths, of which 188 were because of CRC. In the multivariable adjusted models, compared with nondrinkers, patients who consumed at least 4 cups of coffee per day had a 52% lower risk of CRC-specific death (hazard ratio [HR] 0.48; 95% CI, 0.28-0.83; P for trend=.003) and 30% reduced risk of all-cause death (HR, 0.70; 95% CI, 0.54-0.91; P for trend <.001). High intake of caffeinated and decaffeinated coffee (2 or more cups/day) was associated with lower risk of CRC-specific mortality and all-cause mortality. When coffee intake before vs after CRC diagnosis were examined, compared with patients consistently consuming low amounts (less than 2 cups/day), those who maintained a high intake (2 or more cups/day) had a significantly lower risk of CRC-specific death (multivariable HR, 0.63; 95% CI, 0.44-0.89) and death from any cause (multivariable HR, 0.71; 95% CI, 0.60-0.85).

CONCLUSIONS

In an analysis data from the Nurses' Health Study and Health Professionals Follow-up Study, we associated intake of caffeinated and decaffeinated coffee after diagnosis of CRC with lower risk of CRC-specific death and overall death. Studies are needed to determine the mechanisms by which coffee might reduce CRC progression.

Colonoscopy surveillance for high risk polyps does not always prevent colorectal cancer

AIM

To determine the frequency and risk factors for colorectal cancer (CRC) development among individuals with resected advanced adenoma (AA)/traditional serrated adenoma (TSA)/advanced sessile serrated adenoma (ASSA).

METHODS

Data was collected from medical records of 14663 subjects found to have AA, TSA, or ASSA at screening or surveillance colonoscopy. Patients with inflammatory bowel disease or known genetic predisposition for CRC were excluded from the study. Factors associated with CRC developing after endoscopic management of high risk polyps were calculated in 4610 such patients who had at least one surveillance colonoscopy within 10 years following the original polypectomy of the incident advanced polyp.

RESULTS

84/4610 (1.8%) patients developed CRC at the polypectomy site within a median of 4.2 years (mean 4.89 years), and 1.2% (54/4610) developed CRC in a region distinct from the AA/TSA/ASSA resection site within a median of 5.1 years (mean 6.67 years). Approximately, 30% (25/84) of patients who developed CRC at the AA/TSA/ASSA site and 27.8% (15/54) of patients who developed CRC at another site had colonoscopy at recommended surveillance intervals. Increasing age; polyp size; male sex; right-sided location; high degree of dysplasia; higher number of polyps resected; and piecemeal removal were associated with an increased risk for CRC development at the same site as the index polyp. Increasing age; right-sided location; higher number of polyps resected and sessile endoscopic appearance of the index AA/TSA/ASSA were significantly associated with an increased risk for CRC development at a different site.

CONCLUSION

Recognition that CRC may develop following AA/TSA/ASSA removal is one step toward improving our practice efficiency and preventing a portion of CRC related morbidity and mortality.

DNA hypermethylation as a predictor of extramural vascular invasion (EMVI) in rectal cancer

PURPOSE

DNA hypermethylation in gene promoter regions (CpG islands) is emerging as an important pathway in colorectal cancer tumourigenesis. Whilst genetic mutations have been associated with extramural vascular invasion (EMVI) in rectal cancer, no such association has yet been made with epigenetic factors.

METHODS

100 consecutive neoadjuvant-naïve patients undergoing curative surgery for rectal were classified according to the presence or absence of EMVI on histopathological examination. DNA was extracted from tumours and subjected to bisulfite conversion and methylation-specific PCR to determine CIMP status (high, intermediate, or low; according to a validated panel of 8 genes). CIMP status was correlated with EMVI status, histopathological, clinical, and demographic variables, in addition to overall (OS) and disease free (DFS) survival.

RESULTS

51 patients were characterised as CIMP-low, 48 CIMP-intermediate, and one patient CIMP-high. EMVI-positivity was associated with CIMP-intermediate epigenotype (p < 0.001). Patients with EMVI-positive tumours were found to have significantly more advanced disease by pT, pN, and pAJCC categorisation (p = 0.002, p < 0.001, and = p < 0.001, respectively). EMVI-positivity was significantly associated with the requirement for adjuvant chemotherapy (p < 0.001), and worse DFS but not OS (p = 0.012 and p = 0.052).

CONCLUSIONS

Given the association between CIMP-intermediate epigenotype and EMVI-positivity, and the subsequent disadvantage in pathological stage, requirement for adjuvant therapy and worse survival, tumour epigenotyping could potentially play an important role in personalising patients' cancer care. Further work is required to understand the mechanisms that underlie the observed effect, with the hope that they may provide novel opportunities for intervention and inform treatment decisions in rectal cancer.

Totally robotic single docking low anterior resection for rectal cancer: pearls and pitfalls

Total robotic resection of mid- and low rectal cancers confers technical advantages within the confines of the pelvis and allows difficult rectal cancer cases to be performed efficiently with less risk of conversion to open. To maximize the advantage of robotic surgery, we utilize the technique of single docking totally robotic dissection for rectal cancer for both the Da Vinci Si and Xi Surgical Systems. All steps are performed robotically, with the surgery divided into two phases. The first phase consists of inferior mesenteric artery and vein ligation, sigmoid and descending colon mobilization and splenic flexure takedown. Phase two is rectal dissection and pelvic total mesorectal excision. In this article, which is complemented by a video, we describe in detail our surgical technique for totally robotic dissection for rectal cancer using a standardized 'medial to lateral' approach with emphasis on the pearls and pitfalls of this surgery.

Sexual Function and Health-Related Quality of Life in Long-Term Rectal Cancer Survivors

INTRODUCTION

Sexual dysfunction is a treatment sequela in survivors of rectal cancer (RC). Differences in health-related quality of life (HRQOL) can occur based on ostomy status (permanent ostomy vs anastomosis).

AIM

To describe alterations in sexual function and HRQOL based on ostomy status in long-term (≥5 years) survivors of RC.

METHODS

Survivors of RC with an ostomy (n = 181) or anastomosis (n = 394) were surveyed using validated HRQOL and functional status tools. We compared sexuality outcomes between the ostomy and anastomosis groups and reported differences adjusted for clinical and demographic characteristics. Qualitative data from one open-ended question on survivors' greatest challenges since their surgery were analyzed to explore sexuality, symptoms, and relationships.

MAIN OUTCOME MEASURES

Whether sexually active, satisfaction with sexual activity, and select sexual dysfunction items from the Modified City of Hope Quality of Life-Colorectal.

RESULTS

Survivors with a permanent ostomy were more likely to have been sexually inactive after surgery if it occurred before 2000 and experience dissatisfaction with appearance, interference with personal relationships and intimacy, and lower overall HRQOL. Female survivors of RC with an ostomy were more likely to have problems with vaginal strictures and vaginal pain after surgery that persisted at the time of the survey (≥5 years later). Radiation treatment, tumor stage, soilage of garments in bed, and higher Charlson-Deyo comorbidity scores were negatively associated with outcomes. Six qualitative themes emerged: loss of and decreased sexual activity, psychological issues with sexual activity, physical issues with sexual activity, partner rejection, ostomy interference with sexual activity, and positive experiences with sexuality.

CONCLUSION

Sexual dysfunction is a common long-term sequela of RC treatment, with more problems observed in survivors with a permanent ostomy. This warrants widespread implementation of targeted interventions to manage sexual dysfunction and improve HRQOL for these survivors.

Predicted Increases in Incidence of Colorectal Cancer in Developed and Developing Regions, in Association With Ageing Populations

BACKGROUND & AIMS

Population growth and changes in demographic structure are linked to trends in colorectal cancer (CRC) incidence. The aim of this study is to estimate future CRC incidence in the ageing population, and compare trends across developing and developed regions.

METHODS

Cancer and population data were extracted from the International Agency for Research on Cancer. Annual incidence rates for the major types of cancer in 118 selected populations were extracted from 102 cancer registries in 39 countries worldwide. We selected 8 jurisdictions (from the United States, Europe, and Asia) that reported 20-year cancer incidence rates since 1988. Time series models were constructed to project cancer incidence, by sex and age, to 2030. Incidence rates for persons older than 65 years were combined and further adjusted for change of ageing population. We compared age-adjusted incidence rates among the jurisdictions.

RESULTS

The total population older than 65 years old was 12,917,794 in 1988, and the number increased by almost 40% to 17,950,115 in 2007. In developed countries in the West CRC incidence is predicted to decrease by 16.3% in the United States, increase by 4.8% in the United Kingdom, and increase by 4.7% in Sweden by 2030. In developing countries, such as China (Shanghai), Croatia, and Costa Rica, CRC incidence is predicted to increase in a steep curve by 2030 because of the growing population and ageing effect; in 2030, the incidence increases were 60.5% for China, 47.0% for Croatia, and 18.5% for Costa Rica. We also predict CRC incidence will increase greatly by 2030 in Japan and Hong Kong, which are developed regions.

CONCLUSIONS

With the exception of the United States, the incidence of CRC is expected to continue to rise in most regions in the coming decades, due to population growth and changes in demographic structure. The predicted increases are more marked in developing regions with limited health care resources.

The incidence of incisional hernias following ileostomy reversal in colorectal cancer patients treated with anterior resection

INTRODUCTION The aim of this study was to identify the rate of incisional hernia formation following ileostomy reversal in patients who underwent anterior resection for colorectal cancer. In addition, we aimed to ascertain risk factors for the development of reversal-site incisional hernias and to record the characteristics of the resultant hernias. MATERIALS AND METHODS Using a prospectively compiled database of colorectal cancer patients who were treated with anterior resection, we identified individuals who had undergone both ileostomy formation and subsequent reversal of their ileostomies from January 2005 to December 2014. Medical records were reviewed to record descriptive patient data about risk factors for hernia formation, operative details and any subsequent operations. Computed tomography reports were reviewed to identify the number, site and characteristics of incisional hernias. RESULTS A total of 121 patients were included in this study; 14.9% (n = 18) developed an incisional hernia at the ileostomy reversal site; 17.4% (n = 21) at a non-ileostomy site and 6.6% (n = 8) developed both. The reversal-site hernias were smaller both in width and length compared with the non-ileostomy-site hernias. Risk factors for the development of reversal-site incisional hernias were higher body mass index (BMI), lower age, open surgery, longer reversal time and a history of previous hernias. We did not detect a difference in the size of the incisional hernias that developed in patients with these specific risk factors. CONCLUSIONS Incisional hernias are a significant complication of ileostomy reversal. Further evaluation of the use of prophylactic mesh to reduce the incidence of incisional hernias may be worthwhile.

Successful Treatment of a Large Pelvic Abscess Using Intraluminal VAC: A Case Report

The most feared complication of the surgical treatment of rectal cancer is anastomotic leakage, which is related to high rates of mortality and morbidity. Here, we present a patient who could not be treated with surgical drainage but treated by intraluminal Vacuum Associated Closure (VAC). A 34-year-old male patient was treated for rectal cancer by low anterior resection, colorectal anastomosis, and diverting ileostomy following neoadjuvant CRT. The patient reported with a postoperative anastomotic disruption and a large pelvic abscess. Due to the continuation of foul-smell drainage inspite of perianal incision and drainage, intraluminal VAC was applied and the pelvic abscess and the foul-smell were successfully treated. The presence of an adequate anal sphincter tonus is a disadvantage in anastomotic leakage, since it prevents the emptying of the intestinal content and also precludes the drainage of the pelvic abscess. The endoluminal application of VAC, similar to the results of application of VAC in open wounds, has been demonstrated to decrease fibrin and necrotic tissue in the pelvic cavity and increase granulation tissue. VAC, which has long been used in the treatment of open wounds, is a promising method in the treatment of large pelvic abscesses due to anastomotic leakage following rectum resection.

Clinical application of precise radiotherapy in rectal cancer

Precise radiotherapy plays an important role in the comprehensive multidisciplinary therapy of rectal cancer. The mainstream technology is the intensity modulated radiation therapy (IMRT). The technique of repetitive body positioning and the filling of the bladder and rectum are the important factors influencing the accuracy and efficacy of radiotherapy for rectal cancer. The quality of life for patients with rectal cancer is highly affected by side effects associated with radiotherapy. The application of precise positioning technique and image guided radiotherapy (IGRT) can significantly contribute to the accurate delivery of radiotherapy to the region of rectal cancer to improve the local tumor control and reduce unnecessary exposure of normal tissues to irradiation. In this paper, the clinical application of precise positioning technique and the improvement of accurate delivery of radiotherapy are comprehensively reviewed.

Tumor Volume Reduction Rate Predicts Pathologic Tumor Response of Locally Advanced Rectal Cancer Treated with Neoadjuvant Chemotherapy alone: Results from a Prospective Trial

Purpose: To evaluate tumor volume reduction rate (TVRR) measured by three-dimensional region-of-interest (3D-ROI) magnetic resonance (MR) volumetry in predicting pathological tumor response of preoperative chemotherapy alone for locally advanced rectal cancer (LARC).

Methods: LARC patients who received neoadjuvant chemotherapy only from a prospective and randomized trial were recruited. Tumor volumes were measured with 3D-ROI MR volumetry. TVRR was determined using the equation TVRR = (V_Pre-Therapy - V_{Post-Therapy)} / V_Pre-Therapy ×100%. Correlation between TVRR and clinical or pathological characteristics and predictive value of TVRR for pathological tumor response in terms of Tumor Regression Grade (TRG), T downstage, N downstage and overall downstage were analyzed.

Results: 80 eligible cases of LARC were included in our study with TVRR of (51.7±25.1) %. TVRR was higher in well-differentiated tumors compared with poor-differentiated tumors (P=0.040). TVRR was found to be related with TRG (P<0.001), T downstage (P<0.001) and overall downstage (P<0.001). Risk of achieving TRG 2/3 decreased to 57.5% (P=0.002) and odds of achieving overall downstage increase to 179.3% (P<0.001) when TVRR increased by every 10%. A sensitivity of 0.704 and specificity of 0.804 were calculated when ROC curve was constructed to predict TRG using TVRR with a cutoff of 65%.

Conclusion: TVRR is correlated with TRG and overall downstage significantly in LARC patients treated with preoperative chemotherapy alone and shows great value in predicting favorable TRG and overall downstage with good sensitivity and specificity. It could be considered as a promising parameter candidate for efficacy evaluation.

Tumor SUVmax Normalized to Liver Uptake on (18)F-FDG PET/CT Predicts the Pathologic Complete Response After Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

PURPOSE

This study investigates the feasibility of using (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) to predict the pCR (pathologic complete response) rate after neoadjuvant chemoradiotherapy (NCRT) in patients with locally advanced rectal cancer.

METHODS

A total of 88 patients with locally advanced rectal cancer were retrospectively analyzed. All patients were treated with NCRT, followed by radical surgery, and (18)F-FDG PET/CT was performed before and after NCRT. For a semiquantitative assessment, a volume of interest was drawn, including the whole tumor region, and the maximum SUV (SUVmax), SUVmax normalized to liver uptake (SLR), SUVmax normalized to blood pool uptake (SBR), the metabolic tumor volume at SUV 2.0 (MTV[2.0]), SUV 2.5 (MTV[2.5]), and SUV 3.0 (MTV[3.0]) were measured. In addition, their percentage changes after NCRT were assessed. The pCR was verified through a histologic examination of postsurgical specimens. A receiver operating characteristic curve analysis was conducted to predict the pCR by using these PET parameters.

RESULTS

The pCR was predicted in 17 patients (19 %). The values of the area under the curve (AUC) for predicting the pCR were 0.774 for SUVmax after NCRT, 0.826 for SLR after NCRT, 0.815 for SBR after NCRT, 0.724 for MTV(2.5) after NCRT, 0.729 for the percentage change in SUVmax, 0.700 for the percentage change in SLR, and 0.749 for the percentage change in MTV (2.5). Among these PET parameters, SLR after NCRT showed the highest AUC value. The optimal criterion, sensitivity, specificity, and accuracy of SLR after NCRT for predicting the pCR were ≤1.41, 88 %, 65 %, and 68 %, respectively.

CONCLUSIONS

F-FDG PET was found to be useful for predicting the pCR after NCRT in patients with locally advanced rectal cancer. Among various PET parameters, SUVmax normalized to liver uptake after NCRT was the best predictor of the pCR.