The Multidisciplinary Management of Rectal Cancer

Rectal Cancer: Are 12 Lymph Nodes the Limit?

Lymph node dissection is a crucial element of oncologic rectal surgery. Many guidelines regard the removal of at least 12 lymph nodes as the quality criterion in rectal cancer. However, this recommendation remains controversial. This study examines the factors influencing the lymph node yield and the validity of the 12-lymph node limit. Patients with rectal cancer who underwent low anterior resection or abdominoperineal amputation between 2000 and 2010 were analyzed. In total, 20,966 patients from 381 hospitals were included. Less than 12 lymph nodes were found in 20.53% of men and 19.31% of women (p = 0.03). The number of lymph nodes yielded increased significantly from 2000, 2005 and 2010 within the quality assurance program for all procedures. The univariate analysis indicated a significant (p < 0.001) correlation between lymph node yield and gender, age, pre-therapeutic T-stage, risk factors and neoadjuvant therapy. The multivariate analyses found T3 stage, female sex, the presence of at least one risk factor and neoadjuvant therapy to have a significant influence on yield. The probability of finding a positive lymph node was proportional to the number of examined nodes with no plateau. There is a proportional relationship between the number of examined lymph nodes and the probability of finding an infiltrated node. Optimal surgical technique and pathological evaluation of the specimen cannot be replaced by a numeric cut-off value.

Impact of Treatment Coordination on Overall Survival in Rectal Cancer

BACKGROUND

Rectal cancer treatment is often multimodal, comprising of surgery, chemotherapy, and radiotherapy. However, the impact of coordination between these modalities is currently unknown. We aimed to assess whether delivery of nonsurgical therapy within same facility as surgery impacts survival in patients with rectal cancer.

METHODS

A patient cohort with rectal cancer stages II to IV who received multimodal treatment between 2004 and 2016 from National Cancer Database was retrospectively analyzed. Patients were categorized into three groups: (A) surgery + chemotherapy + radiotherapy at same facility (surgery + 2); (B) surgery + chemotherapy or radiotherapy at same facility (surgery + 1); or (C) only surgery at reporting facility (chemotherapy + radiotherapy elsewhere; surgery + 0). The primary outcome was 5-year overall survival (OS), analyzed using Kaplan-Meier curves, log-rank tests, and Cox proportional-hazards models.

RESULTS

A total of 44,716 patients (16,985 [37.98%] surgery + 2, 12,317 [27.54%] surgery + 1, and 15,414 [34.47%] surgery + 0) were included. In univariate analysis, we observed that surgery+2 patients had significantly greater 5-year OS compared to surgery + 1 or surgery + 0 patients (5-year OS: 63.46% vs 62.50% vs 61.41%, respectively; P= .002). We observed similar results in multivariable Cox proportional-hazards analysis, with surgery + 0 group demonstrating increased hazard of mortality when compared to surgery + 2 group (HR: 1.09; P< .001). These results held true after stratification by stage for stage II (HR 1.10; P= .022) and stage III (HR 1.12; P< .001) but not for stage IV (P= .474).

CONCLUSION

Greater degree of care coordination within the same facility is associated with greater OS in patients with stage II to III rectal cancer. This finding illustrates the importance of interdisciplinary collaboration in multimodal rectal cancer therapy.

Malignant colo-duodenal fistula: management based on proposed classification

Duodenal involvement in colonic malignancy is a rare event and poses challenge to surgeons as it may entail major resection in a malnourished patient. Nine patients with malignant colo-duodenal fistula were reviewed retrospectively. Depending on the pattern of duodenal involvement, it was classified as-type I involving lateral duodenal wall less than half circumference; type II involving more than half circumference away from papilla; type III involving more than half circumference close to papilla. Type I was managed with sleeve resection, type II with segmental and type III with pancreaticoduodenectomy. Median age was 47 years, with male to female ratio of 2:1. Eight patients had anemia and seven had hypoproteinemia. Tumor was located in right colon in eight patients and distal transverse colon in one. Diagnosis of fistula was established by CT abdomen in seven (78%), foregut endoscopy in three and intraoperatively in two patients. Two patients had metastatic disease. Elective resection was done in seven while two required emergence surgery. Five patients underwent sleeve resection of the duodenum, two underwent segmental resection and two required pancreaticoduodenectomy. All patients had negative resection margin. One patient died. Median survival was 14 months in eight survivors. Duodenal resection in malignant colo-duodenal fistula should be tailored based on the extent and pattern of duodenal involvement. Negative margin can be achieved even with sleeve resection. En bloc pancreaticoduodenectomy is sometimes required due to extensive involvement. Resection with negative margin can achieve good survival.

NEOADJUVANT THERAPY AND SURGERY FOR RECTAL CANCER. Comparative study between partial and complete pathological response

BACKGROUND

The approach of locally advanced extra-peritoneal rectal adenocarcinoma implies a treatment with neoadjuvant chemoradiotherapy associated with total mesorectal excision surgery. However, the tumors respond variably to this neoadjuvant therapy, and the mechanisms for response are not completely understood.

OBJECTIVE

Evaluate the variables related to the complete tumor response and the outcomes of patients who underwent surgery, comparing those with partial tumor regression and those with total remission of rectal lesion, at the pathological examination.

METHODS

Retrospective analysis of medical records of 212 patients operated between 2000 and 2010, in which 182 (85.9%) obtained partial remission at neoadjuvant therapy (Group 1) and 30 (14.1%), total remission (Group 2).

RESULTS

No difference was found between the groups in relation to gender, ethnicity, age, tumor distance from the anal verge, occurrence of metastases and synchronous lesions on preoperative staging, dose of radiotherapy and performed surgery. In Group 2, was verified high rate of complete remission when the time to surgery after neoadjuvant therapy was equal or less than 8 weeks (P=0.027), and a tendency of lower levels of pretreatment carcinoembryonic antigen (P=0.067). In pathological analysis, the Group 1 presented in relation to Group 2, more affected lymph nodes (average 1.9 and 0.5 respectively; P=0.003), more angiolymphatic (19.2% and 3.3%; P=0.032) and perineural involvement (15.4% and 0%; P=0.017) and greater number of lymph nodes examined (16.3 and 13.6; P=0.023). In the late follow-up, Group 1 also had lower overall survival than Group 2 (94.1 months and 136.4 months respectively; P=0.02) and disease-free survival (85.5 months and 134.6 months; P=0.004). There was no statistical difference between Group 2 and Group 1 in local recurrence (15% and 3.4%, respectively) and distant metastasis (28% and 13.8%, respectively).

CONCLUSION

In this study, the only factor associated with complete remission of rectal adenocarcinoma was the time between neoadjuvant therapy and surgery. This group of patients had less affected lymph nodes, less angiolymphatic and perineural involvement, a longer overall and disease-free survival, but no significant statistical difference was observed in local recurrence and distant metastasis. Although the complete pathologic remission was associated with better prognosis, this not implied in the cure of the disease for all patients.

Understanding the surgical pitfalls in total mesorectal excision: Investigating the histology of the perirectal fascia and the pelvic autonomic nerves

AIM

Excellent understanding of fasciae and nerves surrounding the rectum is necessary for total mesorectal excision (TME). However, fasciae anterolateral to the rectum and surrounding the low rectum are still poorly understood. We studied the perirectal fascia enfolding the extraperitoneally located part of the rectum in en-bloc cadaveric specimens and the University Medical Center Utrecht (UMCU) pelvic dataset, and describe implications for TME.

METHODS

Four donated human adult cadaveric specimens (two males, two females) were obtained through the Leeds GIFT Research Tissue Programme. Paraffin-embedded blocks were produced and serially sectioned at 50 and 250 μm intervals. Whole mount sections were stained with haematoxylin & eosin, Masson's trichrome and Millers' elastin. Additionally, the UMCU pelvic dataset including digitalised cryosections of a female pelvis in three axes was studied.

RESULTS

The mid and lower rectum were surrounded by a multi-layered perirectal fascia, of which the mesorectal fascia (MRF) and parietal fascia bordered the 'holy plane'. There was no extra constant fascia forming a potential surgical plane. Nerves ran laterally to the MRF. More caudally, the mesorectal fat strongly reduced and the MRF approached the rectal muscularis propria. The MRF had a variable appearance in terms of thickness and completeness, most prominently at the anterolateral lower rectum.

CONCLUSION

Dissection onto the MRF allows nerve preservation in TME. Rectal surgeons are challenged in doing so as the MRF varies in thickness and shows gaps, most prominently at the anterolateral lower rectum. At this site, the risk of entering the mesorectum is great and may result in an incomplete specimen.

Whole mount microscopic sections reveal that Denonvilliers' fascia is one entity and adherent to the mesorectal fascia; implications for the anterior plane in total mesorectal excision?

BACKGROUND

Excellent anatomical knowledge of the rectum and surrounding structures is essential for total mesorectal excision (TME). Denonviliers' fascia (DVF) has been frequently studied, though the optimal anterior plane in TME is still disputed. The relationship of the lateral edges of DVF to the autonomic nerves and mesorectal fascia is unclear. We studied whole mout microscopic sections of en-bloc cadaveric pelvic exenteration and describe implications for TME.

METHODS

Four donated human adult cadaveric specimens (two males, two females) were obtained from the Leeds GIFT Research Tissue Programme. Paraffin-embedded mega blocks were produced and serially sectioned at 50 and 250 μm intervals. Sections were stained with haematoxylin & eosin, Masson's trichrome and Millers' elastin. Additionally, a series of eleven human fetal specimens (embryonic age of 9-20 weeks) were studied.

RESULTS

DVF consisted of multiple fascial condensations of collagen and smooth muscle fibres and was indistinguishable from the anterior mesorectal fascia and the prostatic fascia or posterior vaginal wall. The lateral edges of DVF appeared fan-shaped and the most posterior part was continuous with the mesorectal fascia. Fasciae were not identified in fetal specimens.

CONCLUSION

DVF is adherent to and continuous with the mesorectal fascia. Optimal surgical dissection during TME should be carried out anterior to DVF to ensure radical removal, particularly for anterior tumours. Autonomic nerves are at risk, but can be preserved by closely following the mesorectal fascia along the anterolateral mesorectum. The lack of evident fasciae in fetal specimens suggested that these might be formed in later developmental stages.

Multidisciplinary treatment of rectal cancer in 2014: where are we going?

In the present review we discuss the recent developments and future directions in the multimodal treatment of locally advanced rectal cancer, with respect to staging and re-staging modalities, to the current role of neoadjuvant chemo-radiation and to the conservative and more limited surgical approaches based on tumour response after neoadjuvant combined therapy. When initial tumor staging is considered a high accuracy has been reported for T pre-treatment staging, while preoperative lymph node mapping is still suboptimal. With respect to tumour re-staging, all the current available modalities still present a limited accuracy, in particular in defining a complete response. The role of short vs long-course radiotherapy regimens as well as the optimal time of surgery are still unclear and under investigation by means of ongoing randomized trials. Observational management or local excision following tumour complete response are promising alternatives to total mesorectal excision, but need further evaluation, and their use outside of a clinical trial is not recommended. The preoperative selection of patients who will benefit from neoadjuvant radiotherapy or not, as well as the proper identification of a clinical complete tumour response after combined treatment modalities,will influence the future directions in the treatment of locally advanced rectal cancer.

Management of rectal cancers in relation to treatment guidelines: a population-based study comparing Italian and French patients

BACKGROUND

Few studies have investigated rectal cancer management at the population level. We compared how rectal cancers diagnosed in Italy (2003-2005) and France (2005) were managed, and evaluated the extent to which management adhered to European guidelines.

METHODS

Samples of 3938 Italian and 2287 French colorectal cancer patients were randomly extracted from 8 and 12 cancer registries respectively. Rectal cancer patients (860 Italian, 559 French) were analysed. Logistic regression models estimated odds ratios (ORs) of being treated with curative intent, receiving sphincter-saving surgery, and receiving preoperative radiotherapy.

RESULTS

Similar proportions of Italian and French patients were treated with curative intent (70% vs. 67%; OR=0.92 [0.73-1.16]); the respective proportions receiving sphincter-saving surgery were 21% and 33% (OR=1.15 [0.86-1.53]). In about 50% of those treated with curative intent, ≥ 12 lymph nodes were harvested in both countries. The proportion receiving postoperative radiotherapy was higher in Italy than in France (25% vs. 11%, p<0.01), but French patients were more likely to receive preoperative radiotherapy (52% vs. 21%; OR=4.06 [2.79-5.91]).

CONCLUSION

The proportions of patients receiving preoperative radiotherapy and the numbers of lymph nodes sampled were low in both countries. Centralising treatment and potentiating screening would be practical ways of improving outcomes and adhering to guidelines.

Evolving treatment strategies for colorectal cancer: A critical review of current therapeutic options

Management of rectal cancer has markedly evolved over the last two decades. New technologies of staging have allowed a more precise definition of tumor extension. Refinements in surgical concepts and techniques have resulted in higher rates of sphincter preservation and better functional outcome for patients with this malignancy. Although, preoperative chemoradiotherapy followed by total mesorectal excision has become the standard of care for locally advanced tumors, many controversial matters in management of rectal cancer still need to be defined. These include the feasibility of a non-surgical approach after a favorable response to neoadjuvant therapy, the ideal margins of surgical resection for sphincter preservation and the adequacy of minimally invasive techniques of tumor resection. In this article, after an extensive search in PubMed and Embase databases, we critically review the current strategies and the most debatable matters in treatment of rectal cancer.

Patterns and prognosis of locally recurrent rectal cancer following multidisciplinary treatment

AIM: To investigate the patterns and decisive prognostic factors for local recurrence of rectal cancer treated with a multidisciplinary team (MDT) modality.

METHODS: Ninety patients with local recurrence were studied, out of 1079 consecutive rectal cancer patients who underwent curative surgery from 1999 to 2007. For each patient, the recurrence pattern was assessed by specialist radiologists from the MDT using imaging, and the treatment strategy was decided after discussion by the MDT. The associations between clinicopathological factors and long-term outcomes were evaluated using both univariate and multivariate analysis.

RESULTS: The recurrence pattern was classified as follows: Twenty-seven (30%) recurrent tumors were evaluated as axial type, 21 (23.3%) were anterior type, 8 (8.9%) were posterior type, and 13 (25.6%) were lateral type. Forty-one patients had tumors that were evaluated as resectable by the MDT and ultimately received surgery, and R0 resection was achieved in 36 (87.8%) of these patients. The recurrence pattern was closely associated with resectability and R0 resection rate (P < 0.001). The recurrence pattern, interval to recurrence, and R0 resection were significantly associated with 5-year survival rate in univariate analysis. Multivariate analysis showed that the R0 resection was the unique independent factor affecting long-term survival.

CONCLUSION: The MDT modality improves patient selection for surgery by enabling accurate classification of the recurrence pattern; R0 resection is the most significant factor affecting long-term survival.

A computer-aided algorithm to quantitatively predict lymph node status on MRI in rectal cancer

OBJECTIVE

The aim of this study was to demonstrate the principle of supporting radiologists by using a computer algorithm to quantitatively analyse MRI morphological features used by radiologists to predict the presence or absence of metastatic disease in local lymph nodes in rectal cancer.

METHODS

A computer algorithm was developed to extract and quantify the following morphological features from MR images: chemical shift artefact; relative mean signal intensity; signal heterogeneity; and nodal size (volume or maximum diameter). Computed predictions on nodal involvement were generated using quantified features in isolation or in combinations. Accuracies of the predictions were assessed against a set of 43 lymph nodes, determined by radiologists as benign (20 nodes) or malignant (23 nodes).

RESULTS

Predictions using combinations of quantified features were more accurate than predictions using individual features (0.67-0.86 vs 0.58-0.77, respectively). The algorithm was more accurate when three-dimensional images were used (0.58-0.86) than when only middle image slices (two-dimensional) were used (0.47-0.72). Maximum node diameter was more accurate than node volume in representing the nodal size feature; combinations including maximum node diameter gave accuracies up to 0.91.

CONCLUSION

We have developed a computer algorithm that can support radiologists by quantitatively analysing morphological features of lymph nodes on MRI in the context of rectal cancer nodal staging. We have shown that this algorithm can combine these quantitative indices to generate computed predictions of nodal status which closely match radiological assessment. This study provides support for the feasibility of computer-assisted reading in nodal staging, but requires further refinement and validation with larger data sets.

Morphology and prognostic value of tumor budding in rectal cancer after neoadjuvant radiotherapy

Tumor budding is an acknowledged prognostic marker in colorectal cancer. This study was conducted to investigate the morphology and prognostic significance of budding in rectal cancer after neoadjuvant radiotherapy. Surgical specimens from 96 consecutive patients who underwent neoadjuvant radiotherapy and curative resection were retrieved to assess budding and other clinicopathologic factors. The morphology and prognostic significance of postirradiation tumor budding were closely associated with tumor regression grade. In the tumor regression grade 1 group, tumor budding presented as "false budding" and did not have a significant association with prognosis. In the tumor regression grade 2 and 3 groups, budding was observed surrounded by radiation-induced fibrosis and large populations of infiltrating inflammatory cells, and budding intensity was significantly associated with histologic differentiation, ypN stage, and lymphovascular invasion (P < .05). Moreover, the low-grade budding subgroup showed a significantly higher rate of 5-year disease-free survival than the high-grade budding subgroup (87.5% versus 55.6%, P < .0001). Multivariate analysis showed that pretreatment serum carcinoembyronic antigen, tumor regression grade, and tumor budding were the major independent factors affecting long-term disease-free survival. In conclusion, postirradiation budding has distinct morphology and prognostic significance in rectal cancer after neoadjuvant radiotherapy.

Oncologic outcomes of primary and post-irradiated early stage rectal cancer: A retrospective cohort study

AIM: To evaluate the oncologic outcomes of primary and post-irradiated early stage rectal cancer and the effectiveness of adjuvant chemotherapy for rectal cancer patients.

METHODS: Eighty-four patients with stage I rectal cancer after radical surgery were studied retrospectively and divided into ypstage I group (n = 45) and pstage I group (n = 39), according to their preoperative radiation, and compared by univariate and multivariate analysis.

RESULTS: The median follow-up time of patients was 70 mo. No significant difference was observed in disease progression between the two groups. The 5-year disease-free survival rate was 84.4% and 92.3%, respectively (P = 0.327) and the 5-year overall survival rate was 88.9% and 92.3%, respectively, for the two groups (P = 0.692). The disease progression was not significantly associated with the pretreatment clinical stage in ypstage I group. The 5-year disease progression rate was 10.5% and 19.2%, respectively, for the patients who received adjuvant chemotherapy and for those who rejected chemotherapy in the ypstage I group (P = 0.681).

CONCLUSION: The oncologic outcomes of primary and post-irradiated early stage rectal cancer are similar. Patients with ypstage I rectal cancer may slightly benefit from adjuvant chemotherapy.

Metabolic response of rectal cancer assessed by 18-FDG PET following chemoradiotherapy is prognostic for patient outcome

BACKGROUND

Complete pathological response has proven prognostic benefits in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. Sequential 18-FDG PET may be an early surrogate for pathological response to chemoradiotherapy.

OBJECTIVES

The aim of this study was to identify whether metabolic response measured by FDG PET following chemoradiotherapy is prognostic for tumor recurrence and survival following neoadjuvant therapy and surgical treatment for primary rectal cancer.

METHODS

Patients with primary rectal cancer treated by long-course neoadjuvant chemoradiotherapy followed by surgery had FDG PET performed before and 4 weeks after treatment, before surgical resection was performed. Retrospective chart review was undertaken for patient demographics, tumor staging, recurrence rates, and survival.

RESULTS

: Between 2000 and 2007, 78 patients were identified (53 male, 25 female; median age, 64 y). After chemoradiotherapy, 37 patients (47%) had a complete metabolic response, 26 (33%) had a partial metabolic response, and 14 (18%) had no metabolic response as assessed by FDG PET (1 patient had missing data). However, only 4 patients (5%) had a complete pathological response. The median postoperative follow-up period was 3.1 years during which 14 patients (19%) had a recurrence: 2 local, 9 distant, and 3 with both local and distant. The estimated percentage without recurrence was 77% at 5 years (95% CI 66%-89%). There was an inverse relationship between FDG PET metabolic response and the incidence of recurrence within 3 years (P = .04). Kaplan-Meier analysis of FDG PET metabolic response and overall survival demonstrated a significant difference in survival among patients in the 3 arms: complete, partial, and no metabolic response (P = .04); the patients with complete metabolic response had the best prognosis.

CONCLUSION

Complete or partial metabolic response on PET following neoadjuvant chemoradiotherapy and surgery predicts a lower local recurrence rate and improved survival compared with patients with no metabolic response. Metabolic response may be used to stratify prognosis in patients with rectal cancer.

Efficacy and safety of intraoperative radiotherapy in colorectal cancer: a systematic review

Intraoperative radiotherapy (IORT) has been proposed as an encouraging treatment for colorectal cancer. The aim of this study is to assess the efficacy and safety of IORT for this cancer through a systematic review. Studies located in electronic databases were selected according to established criteria, read and analysed and the results extracted by two independent reviewers. Fifteen studies met the selection criteria. Five-to-six-year local control (LC) was over 80% and 5-year overall survival (OS) was close to 65%. For recurrences, the 5-year overall survival was 30%. The main acute complications were gastrointestinal. Adding IORT to conventional treatment reduces the incidence of local recurrences within the radiation area over 10%. IORT is a safe technique as it does not increase toxicity associated with conventional treatment.

Postgraduate multidisciplinary development program: impact on the interpretation of pelvic MRI in patients with rectal cancer: a clinical audit in West Denmark

BACKGROUND

Pelvic MRI in patients with rectal cancer is an accepted tool for the identification of patients with poor prognostic tumors who may benefit from neoadjuvant therapy. In Denmark, this examination has been mandatory in the workup on rectal cancer since 2002.

OBJECTIVE

This study aimed to assess the impact of a multidisciplinary team course for doctors in West Denmark on the technical quality, reporting, and interpretation of pelvic MRI in rectal cancer.

DESIGN

This study is interventional and observational. Two expert reviewers served as reference standard in the evaluation of consecutively performed pelvic MRI scans against which the evaluations from the participating centers were compared.

SETTINGS

Five imaging centers in West Denmark performed pelvic MRI in rectal cancer from March 1 to December 31, 2007.

PATIENTS

One hundred and eighty patients with newly diagnosed rectal cancer were enrolled.

INTERVENTIONS

This study involved a multidisciplinary team course including on-site visits.

MAIN OUTCOME MEASURES

The MR scans were evaluated concerning technical performance, reporting, interpretation, and the ability to correctly allocate patients to chemoirradiation based on imaging findings pre- and postcourse.

RESULTS

Eighteen percent of the scans were of satisfying technical quality for staging rectal cancer before the course compared with 74% after (P < .001). After the course, the T-stage subclassification, the depth of extramural spread, the N stage, and the presence of extramural vascular invasion was reported significantly more frequently. Based on imaging findings, we observed no significant effect on the ability to perform correct treatment stratification according to Danish guidelines.

LIMITATIONS

The evaluation process itself may have improved the performance of the participating centers.

CONCLUSIONS

Performance and reporting of pelvic MRI in patients with rectal cancer can be improved significantly through multidisciplinary development courses and on-site visits, whereas improvements in image interpretation with regard to treatment stratification may demand more intensive efforts.

How useful is rectal endosonography in the staging of rectal cancer?

It is essential in treating rectal cancer to have adequate preoperative imaging, as accurate staging can influence the management strategy, type of resection, and candidacy for neoadjuvant therapy. In the last twenty years, endorectal ultrasound (ERUS) has become the primary method for locoregional staging of rectal cancer. ERUS is the most accurate modality for assessing local depth of invasion of rectal carcinoma into the rectal wall layers (T stage). Lower accuracy for T2 tumors is commonly reported, which could lead to sonographic overstaging of T3 tumors following preoperative therapy. Unfortunately, ERUS is not as good for predicting nodal metastases as it is for tumor depth, which could be related to the unclear definition of nodal metastases. The use of multiple criteria might improve accuracy. Failure to evaluate nodal status could lead to inadequate surgical resection. ERUS can accurately distinguish early cancers from advanced ones, with a high detection rate of residual carcinoma in the rectal wall. ERUS is also useful for detection of local recurrence at the anastomosis site, which might require fine-needle aspiration of the tissue. Overstaging is more frequent than understaging, mostly due to inflammatory changes. Limitations of ERUS are operator and experience dependency, limited tolerance of patients, and limited range of depth of the transducer. The ERUS technique requires a learning curve for orientation and identification of images and planes. With sufficient time and effort, quality and accuracy of the ERUS procedure could be improved.