Predicting lymph node metastases in rectal cancer

Prognostic Impact of Lymphatic Invasion, Venous Invasion, Perineural Invasion, and Tumor Budding in Rectal Cancer Treated With Neoadjuvant Chemoradiotherapy Followed by Total Mesorectal Excision

BACKGROUND

The diagnostic implications of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in rectal cancer treated with neoadjuvant chemoradiotherapy are unknown.

OBJECTIVE

This study aimed to identify the prognostic impact of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy.

DESIGN

This was a retrospective cohort study.

SETTINGS

This study was conducted at the Samsung Medical Center. Grouping was performed on the basis of lymphatic invasion, venous invasion, perineural invasion, and tumor budding status: no-risk group with 0 factor (n = 299), low-risk group with any 1 factor (n = 131), intermediate-risk group with any 2 factors (n = 75), and high-risk group with 3 or 4 risk factors (n = 32).

PATIENTS

Patients who underwent neoadjuvant chemoradiotherapy, followed by radical operation for locally advanced rectal cancer, from January 2010 to December 2015 were included.

MAIN OUTCOME MEASURES

The main outcome measures were disease-free and overall survival.

RESULTS

Disease-free and overall survival varied significantly between the groups in stage III ( p < 0.001 and p < 0.001). Disease-free survival in stage I differed between the no-risk group and the intermediate-risk group ( p = 0.026). In stage II, disease-free and overall survival differed between the no-risk group and the intermediate-risk group ( p = 0.010 and p = 0.045). In multivariable analysis, risk grouping was an independent prognostic factor for both disease-free (p <0.001) and overall survival ( p < 0.001).

LIMITATIONS

The inherent limitations are associated with the retrospective single-center study design.

CONCLUSIONS

Lymphatic invasion, venous invasion, perineural invasion, and tumor budding are strong prognostic factors for disease-free and overall survival in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. Therefore, adjuvant chemotherapy is strongly recommended in patients with positive lymphatic invasion, venous invasion, perineural invasion, and tumor budding. See Video Abstract at http://links.lww.com/DCR/B919 .

IMPACTO PRONSTICO DE LA INVASIN LINFTICA, LA INVASIN VENOSA, LA INVASIN PERINEURAL Y LA GEMACIN TUMORAL EN EL CNCER DE RECTO TRATADO CON QUIMIORRADIOTERAPIA NEOADYUVANTE SEGUIDA DE ESCISIN TOTAL DEL MESORRECTO

ANTECEDENTES:Se desconocen las implicaciones diagnósticas de la invasión linfática, la invasión venosa, la invasión perineural y el crecimiento tumoral en el cáncer de recto tratado con quimiorradioterapia neoadyuvante.OBJETIVO:Este estudio fue diseñado para identificar el impacto pronóstico de la invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante.DISEÑO:Este estudio fue un estudio de cohorte retrospectivo.AJUSTES:Este estudio se realizó en el Centro Médico Samsung. La agrupación se realizó en función de la invasión linfática, la invasión venosa, la invasión perineural y el estado de crecimiento del tumor: grupo sin riesgo con 0 factores (n = 299), grupo de bajo riesgo con cualquier factor 1 (n = 131), grupo de riesgo intermedio con 2 factores cualquiera (n = 75), y un grupo de alto riesgo con 3 o 4 factores de riesgo (n = 32).PACIENTES:Se incluyeron un total de 537 pacientes que se sometieron a quimiorradioterapia neoadyuvante seguida de operación radical por cáncer de recto localmente avanzado desde enero de 2010 hasta diciembre de 2015.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la supervivencia libre de enfermedad y la supervivencia general.RESULTADOS:La mediana del período de seguimiento fue de 77 meses, y la supervivencia libre de enfermedad a los 5 años y la supervivencia general a los 5 años variaron significativamente entre los grupos en el estadio III (p < 0,001, p < 0,001). La supervivencia libre de enfermedad a los 5 años en el estadio I difirió entre el grupo sin riesgo y el grupo de riesgo intermedio (p = 0,026). En el estadio II, la supervivencia libre de enfermedad a 5 años y la supervivencia global a 5 años difirieron entre el grupo sin riesgo y el grupo de riesgo intermedio p = 0,010, p = 0,045). En el análisis multivariable, la agrupación de riesgo fue un factor pronóstico independiente tanto para la supervivencia libre de enfermedad (p < 0,001) como para la supervivencia global (p < 0,001).LIMITACIÓN:Las limitaciones inherentes están asociadas con el diseño de estudio retrospectivo de un solo centro..CONCLUSIÓN:La invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral son fuertes factores pronósticos para la supervivencia libre de enfermedad y la supervivencia general en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante. Por lo tanto, se recomienda fuertemente la quimioterapia adyuvante en pacientes con invasión linfática positiva, invasión venosa, invasión perineural y tumor en en formacion. Consulte Video Resumen en http://links.lww.com/DCR/B919 . (Traducción-Dr Yolanda Colorado ).

Extramural vascular invasion as an independent prognostic marker in locally advanced rectal cancer: propensity score match pair analysis

BACKGROUND

In rectal cancers, presence of extramural vascular invasion on MRI (mrEMVI) is associated with poor survival. The independent influence of mrEMVI in the presence of other prognostic factors has not been previously analyzed using match pair analysis.

PATIENTS AND METHODS

Consecutive 92 patients having mrEMVI at presentation treated between January 2016 and December 2018 were matched with 92 patients (1:1) without mrEMVI. Matching parameters were T stage, mesorectal fascia involvement, and tumor differentiation. The presence and absence of mrEMVI were correlated to outcomes. An event was defined as locoregional failure or distant metastasis or poor response to chemoradiation rendering the rectal tumor as inoperable.

RESULTS

At 3 years, in the mrEMVI-positive cohort, 59% had an event and in the mrEMVI-negative cohort, 45% had an event (p = 0.026). Local control was 90.2% (12recurrences in 122 who underwent surgery), two recurrences in the mrEMVI-positive cohort and ten patients in the mrEMVI-negative cohort, which missed statistical significance (p = 0.06). Distant metastasis-free survival was significantly worse in the mrEMVI-positive cohort versus the mrEMVI-negative cohort (58.2% vs. 69.4%) (p = 0.022). Similarly, Overall survival was significantly inferior in mrEMVI-positive cohort compared to the mrEMVI-negative cohort (57% vs. 72.4%) (p = 0.02). The multivariate regression analysis confirmed the independent predictive value of mrEMVI.  CONCLUSION: Extramural vascular invasion detected through MRI is an independent risk factor for distant metastasis in the locally advanced carcinoma rectum. Aggressive treatment regimens like total neoadjuvant treatment should be considered in these cases pending randomized control studies.

Lymph Node Positivity in T1/T2 Rectal Cancer: a Word of Caution in an Era of Increased Incidence and Changing Biology for Rectal Cancer

BACKGROUND

The evaluation of lymph nodes in rectal cancer dictates treatment. The goals of this study are to characterize the contemporary rate of lymph node metastasis in early stage rectal cancer and to re-investigate histologic factors that predict positive lymph nodes.

MATERIALS AND METHODS

Using the National Cancer Database, we identified patients with clinical stage I rectal adenocarcinoma. Multivariable logistic regression was used to determine risk factors for lymph node positivity.

RESULTS

12.2% of patients with T1 tumors and 18.0% of patients with T2 tumors had positive lymph nodes. For T1 tumors, positive lymph nodes were present in 9.3% with neither poor differentiation nor lymphovascular invasion (LVI), 17.3% with poor differentiation alone, 34.7% with LVI alone, and 45.0% with both poor differentiation and LVI. For T2 tumors, positive lymph nodes were present in 11.7% with neither poor differentiation nor LVI, 25.3% with poor differentiation alone, 47.3% with LVI alone, and 41.5% with both poor differentiation and LVI. LVI was an independent predictor of positive lymph nodes (OR;4.75,95%CI;3.17-7.11,p < 0.001) for T1 and (OR;6.20,95%CI;4.53-8.51,p < 0.001) T2 tumors.

CONCLUSIONS

T1/T2 tumors have higher rates of positive lymph nodes when poor differentiation and LVI are present. These results should be taken into consideration prior to surgical treatment.

Management of complex polyps of the colon and rectum

PUPRPOSE

Benign polyps that are technically challenging and unsafe to remove via polypectomy are known as complex polyps. Concerns regarding safety and completeness of resection dictate they undergo advanced endoscopic techniques, such as endoscopic mucosal resection or surgery. We provide a comprehensive overview of complex polyps and current treatment options.

METHODS

A review of the English literature was conducted to identifyarticles describing the management of complex polyps of the colon and rectum.

RESULTS

Endoscopic mucosal resection is the standard of care for the majority of complex polyps. Only polyps that fail endoscopic mucosal resection or are highly suspicious of invasive cancer but which cannot be removed endoscopically warrant surgery.

CONCLUSION

Several factors influence the treatment of a complex polyp; therefore, there cannot be a "one-size-fitsall" approach. Treatment should be tailored to the lesion's characteristics, the risk of adverse events, and the resources available to the treating physician.

Modified 3-Point MRI-Based Tumor Regression Grade Incorporating DWI for Locally Advanced Rectal Cancer

OBJECTIVE

The purpose of this study was to evaluate the prognostic relevance of a modified 3-point MRI-based tumor regression grading system incorporating DWI for patients with locally advanced rectal cancer after preoperative chemoradiotherapy (CRT).

MATERIALS AND METHODS

Between March 2012 and September 2013, 118 consecutively registered patients with middle or lower locally advanced rectal cancer who underwent CRT followed by surgery were enrolled in this retrospective study. Two radiologists in consensus assessed MRI tumor regression grade (mrTRG) based on T2-weighted images and high b value DW images (0 and 1000 s/mm²) using the following grades: 0, complete regression (no obvious tumor); 1, intermediate regression (dominant fibrosis, regression > 50%); 2, poor regression (dominant tumor, regression ≤ 50%). Multivariate analysis with a Cox regression model was performed to evaluate the association between modified mrTRG and 3-year disease-free survival (DFS) rate. A Kaplan-Meier method with a log-rank test was used to compare the DFS rate between responder (grades 0 and 1) and nonresponder (grade 2) groups.

RESULTS

Both the accuracy (72.9% vs 38.1%; p < 0.001) and the interreader agreement (κ = 0.580 vs 0.338; p < 0.001) of modified 3-point mrTRG were improved over the established 5-point mrTRG. Modified mrTRG (adjusted hazard ratio, 2.505; 95% CI, 1.231-5.100) was independently associated with 3-year DFS rate (p = 0.011). There was also a significant difference in the 3-year DFS rate between responders (73.8%; 95% CI, 64.2-81.3%) and nonresponders (41.7%; 95% CI, 10.9-70.8%) (p = 0.028).

CONCLUSION

In patients with middle or lower locally advanced rectal cancer, the modified 3-point mrTRG incorporating DWI was independently associated with the 3-year DFS rate after CRT followed by surgery. The grading scale may be used as a surrogate for expected prognosis of preoperative CRT. Further prospective trials are warranted.

Comparative clinicopathological characteristics of colon and rectal T1 carcinoma

Lymph node metastasis significantly influences the management of patients with colorectal carcinoma. It has been observed that the biology of colorectal carcinoma differs by location. The aim of the current study was to retrospectively compare the clinicopathological characteristics of patients with colon and rectal T1 carcinomas, particularly their rates of lymph node metastasis. Of the 19,864 patients who underwent endoscopic or surgical resection of colorectal neoplasms at Showa University Northern Yokohama Hospital, 557 had T1 surgically resected carcinomas, including 457 patients with colon T1 carcinomas and 100 patients with rectal T1 carcinomas. Analysed clinicopathological features included patient age, gender, tumor size, morphology, tumor budding, invasion depth, vascular invasion, histological grade, lymphatic invasion and lymph node metastasis. Rectal T1 carcinomas were significantly larger than colon T1 carcinomas (mean ± standard deviation: 23.7±13.1 mm vs. 19.9±11.0 mm, P<0.01) and were accompanied by significantly higher rates of vascular invasion (48.0% vs. 30.2%, P<0.01). Significant differences were not observed among any other clinicopathological factors. In conclusion, tumor location itself was not a risk factor for lymph node metastasis in colorectal T1 carcinomas, even though on average, rectal T1 carcinomas were larger and accompanied by a significantly higher rate of vascular invasion than colon T1 carcinomas.

MRI Detection of Extramural Venous Invasion in Rectal Cancer: Correlation With Histopathology Using Elastin Stain. AJR Am J Roentgenol. 2016;206:747-755. [PMID: 26933769 DOI: 10.2214/ajr.15.15568]

OBJECTIVE

The purpose of this article is to evaluate the diagnostic performance of MRI for detection of extramural venous invasion (EMVI) compared with histopathologic analysis using elastin stain.

MATERIALS AND METHODS

Forty-nine patients with rectal cancer who had undergone surgical resection with preoperative MRI were identified. Thirty-seven patients had received preoperative chemoradiation therapy (CRT). Sixty-nine MRI studies were independently reviewed by two blinded radiologists for EMVI using a score of 0-4. Comparison was made with histopathologic results obtained by two pathologists reviewing the elastin-stained slides in consensus. EMVI status was also correlated with other tumoral and prognostic features on imaging and pathologic analysis. Statistical analysis was performed using Fisher exact and McNemar tests.

RESULTS

EMVI was present in 31% of the pathology specimens. An MRI EMVI score of 3-4 was 54% sensitive and 96% specific in detecting EMVI in veins 3 mm in diameter or larger. Inclusion of a score of 2 as positive for EMVI increased the sensitivity to 79% but decreased the specificity to 74%, with poor positive predictive value. Preoperative CRT had no significant effect on the diagnostic performance of MRI. Contrast-enhanced MRI increased reader confidence for diagnosis or exclusion of EMVI compared with T2-weighted imaging. EMVI status correlated with depth of extramural invasion and proximity to mesorectal fascia.

CONCLUSION

Despite an anticipated increase in sensitivity for EMVI detection by histopathologic analysis using elastin compared with H and E staining, MRI maintains a high specificity and moderate sensitivity for the detection of EMVI.

Transanal Endoscopic Microsurgery

Transanal endoscopic microsurgery (TEM) was developed by Professor Gerhard Buess 30 years ago at the dawn of minimally invasive surgery. TEM utilizes a closed proctoscopic system whereby endoluminal surgery is accomplished with high-definition magnification, constant CO2 insufflation, and long-shafted instruments. The end result is a more precise excision and closure compared to conventional instrumentation. Virtually any benign lesion can be addressed with this technology; however, proper patient selection is paramount when using it for cancer.

Perineural spread of pelvic malignancies to the lumbosacral plexus and beyond: clinical and imaging patterns

OBJECT

Perineural spread along pelvic autonomie nerves has emerged as a logical, anatomical explanation for selected cases of neoplastic lumbosacral plexopathy (LSP) in patients with prostate, bladder, rectal, and cervical cancer. The authors wondered whether common radiological and clinical patterns shared by various types of pelvic cancer exist.

METHODS

The authors retrospectively reviewed their institutional series of 17 cases concluded as perineural tumor spread. All available history, physical examination, electrodiagnostic studies, biopsy data and imaging studies, evidence of other metastatic disease, and follow-up were recorded in detail. The series was divided into 2 groups: cases with neoplastic lumbosacral plexopathy confirmed by biopsy (Group A) and cases included based on imaging characteristics despite the lack of biopsy or negative biopsy results (Group B).

RESULTS

Group A comprised 10 patients (mean age 69 years); 9 patients were symptomatic and 1 was asymptomatic. The L5–S1 spinal nerves and sciatic nerve were most frequently involved. Three patients had intradural extension. Seven patients were alive at last follow-up. Group B consisted of 7 patients (mean age 64 years); 4 patients were symptomatic, 2 were asymptomatic, and 1 had only imaging available. The L5–S1 spinal nerves and the sciatic nerve were most frequently involved. No patients had intradural extension. Four patients were alive at last follow-up.

CONCLUSIONS

The authors provide a unifying theory to explain lumbosacral plexopathy in select cases of various pelvic neoplasms. The tumor cells can use splanchnic nerves as conduits and spread from the end organ to the lumbosacral plexus. Tumor can continue to spread along osseous and muscle nerve branches, resulting in muscle and bone “metastases.” Radiological studies show a reproducible, although nonspecific pattern, and the same applies to clinical presentation.

The evolution in the detection of extramural venous invasion in rectal cancer: implications for modern-day practice

SUMMARY 

Venous invasion has been considered a poor prognostic factor in rectal cancer for over half a century. This term has evolved in recent years and now applies specifically to tumor invasion into extramural veins – extramural venous invasion. This distinction from intramural venous invasion is important as it is more clinically relevant. Extramural venous invasion can be identified by histopathology and MRI but until recently there has been a lack of consistency in definitions and detection techniques. This paper reviews the historical evidence for the prognostic importance and detection of venous invasion in rectal cancer.

Mismatch repair system and p53 expression in patients with T1 and T2 colorectal cancer: predictive role of lymph node metastasis and survival

BACKGROUND

The aim of this study was to evaluate the predictive role of the mismatch repair (MMR) system and p53 expression for lymph node metastasis and long-term survival in patients with T1 and T2 colorectal cancer.

METHODS

A total of 543 patients with T1 or T2 colorectal cancers who underwent radical surgery with regional lymphadenectomy from December 2007 to December 2009 were analyzed. Predictive factors for lymph node metastasis and prognostic factors were analyzed.

RESULTS

During the median follow-up period of 4 years, the 5-year disease-free survival rate for patients without lymph node metastasis was 94.8%, which was significantly higher than that for those with lymph node metastases (85.2%; P < 0.001). On multivariate analysis, gender, tumor location, N category, lymphatic invasion, vascular invasion, and perineural invasion were independent prognostic factors for disease-free survival; however MMR defect, p53 expression, and microsatellite instability (MSI) were not. The presence of lymphatic invasion, vascular invasion, and tumor budding were independent predictors of lymph node metastasis.

CONCLUSIONS

In patients with T1 or T2 colorectal cancer, lymphatic invasion, vascular invasion, and tumor budding were predictive of lymph node metastasis; however, MMR defect, p53 expression, and MSI were not predictive.

Lymphatic drainage of the rectum, preoperative assessment and its relevance to malignant polyp and rectal cancer management

SUMMARY The importance of lymph node metastasis in rectal cancer is well recognized with regards to prognosis, staging and treatment. Accurate staging is particularly important where neoadjuvant treatment has been shown to downsize and downstage locally advanced tumors. Vascular invasion, poor differentiation and increasing depth of invasion are related to a higher risk of lymph node metastasis in early cancers while advanced, poorly differentiated and low rectal cancers are more likely to have lateral pelvic sidewall nodal involvement. Nodal staging is crucial in the management of malignant rectal polyps, as is the deferral of surgery in patients who have a complete clinical and radiological response to chemoradiotherapy. In all of these situations nodal staging is vital and warrants ongoing evaluation to improve its accuracy.

MRI after treatment of locally advanced rectal cancer: how to report tumor response--the MERCURY experience. AJR Am J Roentgenol. 2012;199:W486-W495. [PMID: 22997398 DOI: 10.2214/ajr.11.8210]

OBJECTIVE

The Magnetic Resonance Imaging and Rectal Cancer European Equivalence (MERCURY) Study validated the use of MRI for posttreatment staging and its correlation with survival outcomes. As a consequence, reassessment of MRI scans after preoperative therapy has implications for surgical planning, the timing of surgery, sphincter preservation, deferral of surgery for good responders, and development of further preoperative treatments for radiologically identified poor responders.

CONCLUSION

In this article we report a validated systematic approach to the interpretation of MR images of patients with rectal cancer after chemoradiation.

Analysis of risk factors for lymph nodal involvement in early stages of rectal cancer: when can local excision be considered an appropriate treatment? Systematic review and meta-analysis of the literature

Background. Over the past ten years oncological outcomes achieved by local excision techniques (LETs) as the sole treatment for early stages of rectal cancer (ESRC) have been often disappointing. The reasons for these poor results lie mostly in the high risk of the disease's diffusion to local-regional lymph nodes even in ESRC. Aims. This study aims to find the correct indications for LET in ESRC taking into consideration clinical-pathological features of tumours that may reduce the risk of lymph node metastasis to zero. Methods. Systematic literature review and meta-analysis of casistics of ESRC treated with total mesorectal excision with the aim of identifying risk factors for nodal involvement. Results. The risk of lymph node metastasis is higher in G ≥ 2 and T ≥ 2 tumours with lymphatic and/or vascular invasion. Other features which have not yet been sufficiently investigated include female gender, TSM stage >1, presence of tumour budding and/or perineural invasion. Conclusions. Results comparable to radical surgery can be achieved by LET only in patients with T(1) N(0) G(1) tumours with low-risk histological features, whereas deeper or more aggressive tumours should be addressed by radical surgery (RS).

Risk factors for lymph node metastasis in pT1 and pT2 rectal cancer: a single-institute experience in 943 patients and literature review

BACKGROUND

Local excision has become an alternative for radical resection in rectal cancer for selected patients. The purpose of this study was to assess the clinicopathologic factors determining lymph node metastasis (LNM) in patients with T1-2 rectal cancer.

METHODS

Between January 1995 and December 2009, a total of 943 patients with pT1 or pT2 rectal adenocarcinoma received radical resection at a single institution. Clinicopathologic factors were evaluated by univariate and multivariate analyses to identify risk factors for LNM.

RESULTS

A total of 943 patients (544 men and 399 women) treated for T1-2 rectal cancer were included in this study. LNM was found in 188 patients (19.9%). In multivariate analysis, lymphovascular invasion (LVI; P < 0.001, hazard ratio 11.472), poor differentiation (PD; P = 0.007, hazard ratio 3.218), and depth of invasion (presence of pT2; P = 0.032, hazard ratio 1.694) were significantly related to nodal involvement. The incidence for LNM lesions in the presence of LVI, PD, and pT2 was 68.8, 50.0, and 23.1%, respectively, while that for pT1 carcinomas with no LVI or PD was 7.5%.

CONCLUSIONS

LVI, PD, and pT2 are independent risk factors predicting LNM in pT1-2 rectal carcinoma.

Risk factors of nodal involvement in T2 colorectal cancer

PURPOSE

Because of the adverse consequences of radical resection of T2 colorectal cancer, criteria are needed for selection of patients who can safely undergo local excision without requiring additional radical surgery. We therefore conducted a retrospective study of patients with T2 colorectal cancer to identify risk factors for nodal involvement that might be used in selecting patients for local excision.

METHODS

We reviewed records from consecutive patients who had undergone curative resection of T2 colorectal cancer at the Department of Surgery, National Defense Medical College, Saitama, Japan, between 1985 and 2005. Data on conventional clinicopathologic variables were retrieved from pathology reports at the time of surgery, and archived slides were evaluated regarding potential risk factors such as extent of poorly differentiated component (grade I-III), myxoid cancer stroma, tumor budding, and growth pattern and invasion depth in the muscularis propria.

RESULTS

A total of 244 patients (139 men and 105 women) treated for T2 colorectal cancer were included. Nodal involvement was found in 7 (8.4%) of 83 patients classified as grade I on the poorly differentiated component vs. 47 (29.2%) of 161 patients classified as grade II or III (P < .001). Of 148 patients negative for myxoid cancer stroma, 30 (16.9%) had nodal involvement vs. 24 (36.4%) of 42 patients who were positive for myxoid cancer stroma (P = .0011). According to multiple variable logistic analysis, significant independent risk factors for nodal involvement included poorly differentiated component (P = .002), myxoid cancer stroma (P = .032), and lymphovascular invasion (P = .022).

CONCLUSIONS

Poorly differentiated component, myxoid cancer stroma, and lymphovascular invasion are significant independent risk factors for nodal involvement in T2 colorectal cancer. We need further study to validate these results on another data set, especially in patients with rectal cancer, and to confirm whether local resection of T2 rectal cancer is able to predict the nodal involvement before laparotomy.

Role of tumor size in the pre-operative management of rectal cancer patients

Background

Clinical management of rectal cancer patients relies on pre-operative staging. Studies however continue to report moderate degrees of over/understaging as well as inter-observer variability. The aim of this study was to determine the sensitivity, specificity and accuracy of tumor size for predicting T and N stages in pre-operatively untreated rectal cancers.

Methods

We examined a test cohort of 418 well-documented patients with pre-operatively untreated rectal cancer admitted to the University Hospital of Basel between 1987 and 1996. Classification and regression tree (CART) and logistic regression analysis were carried out to determine the ability of tumor size to discriminate between early (pT1-2) and late (pT3-4) T stages and between node-negative (pN0) and node-positive (pN1-2) patients. Results were validated by an external patient cohort (n = 28).

Results

A tumor diameter threshold of 34 mm was identified from the test cohort resulting in a sensitivity and specificity for late T stage of 76.3%, and 67.4%, respectively and an odds ratio (OR) of 6.67 (95%CI:3.4-12.9). At a threshold value of 29 mm, sensitivity and specificity for node-positive disease were 94% and 15.5%, respectively with an OR of 3.02 (95%CI:1.5-6.1). Applying these threshold values to the validation cohort, sensitivity and specificity for T stage were 73.7% and 77.8% and for N stage 50% and 75%, respectively.

Conclusions

Tumor size at a threshold value of 34 mm is a reproducible predictive factor for late T stage in rectal cancers. Tumor size may help to complement clinical staging and further optimize the pre-operative management of patients with rectal cancer.

Transanal endoscopic microsurgery: indications, results and controversies

Transanal endoscopic microsurgery (TEM) was introduced in 1983 as a minimally invasive technique allowing the resection of adenomas and early rectal carcinomas unsuitable for local or colonoscopic excision which would otherwise require major surgery. After 25 years, there is still much debate about the procedure. This article presents the TEM technique, indications, results and complications, focusing on its role in rectal cancer. The controversial points addressed include long-term results, TEM in high-risk T1 lesions, TEM associated with combined modality therapy (CMT) for invasive rectal cancer and salvage therapy after TEM. The future perspectives for TEM are promising and its association with CMT will probably expand the select group of patients who will benefit from the procedure.

Ovarian metastases from colorectal cancer: a clinicopathological analysis of 103 patients

OBJECTIVE

To improve management of ovarian metastasis through assessment of clinicopathological features and treatment outcomes associated with ovarian metastasis from colorectal cancer.

METHOD

We recruited 103 subjects who were diagnosed with ovarian metastasis and subjected to surgery between June 1989 and December 2005. Clinical and pathological variables were evaluated. Survival and its associated factors were analysed with a median follow-up of 31 months after ovarian surgery (range 1-129 months).

RESULTS

The mean age at diagnosis was 46 years (range 14-72 years), synchronous ovarian metastasis occurred in 74 patients and metachronous in 29 patients. The primary tumour was more commonly associated with the colon rather than the rectum (84/1608, 5.2%vs 19/1534, 1.2%, P < 0.001). Combined metastases occurred in 69 patients (67%). Complete resection was achieved in 34 (33%) patients without other metastases. The estimated 5-year disease free survival and overall survival rate were 40.1% and 26.6%, respectively. From univariate analysis, lymphovascular invasion (35.6%vs 12.8%, P = 0.034), combined metastasis (50.9%vs 15.6%, P = 0.0035) and bilaterale ovarian metastasis (36.4%vs 10.6%, P = 0.015) were identified as significant poor prognosis factors, and from multivariate analysis combined metastasis and bilaterale ovarian metastasis were significant (P = 0.034 and P = 0.015, respectively).

CONCLUSION

This study suggests a role for regular follow-up computed tomography scans within 6 months postoperatively and tumour marker assays for the early detection of ovarian metastasis in premenopausal women after primary surgery, especially in colonic patients with poor prognostic factors.

Local management of rectal neoplasia

The treatment of rectal neoplasia, whether benign or malignant, challenges the surgeon. The challenge in treating rectal cancer is selecting the proper approach for the appropriate patient. In a small number of rectal cancer patients local excision may be the best approach. In an attempt to achieve two goals-cure of disease with a low rate of local failure and maintenance of function and quality of life-multiple approaches can be utilized. The key to obtaining a good outcome for any one patient is balancing the competing factors that impact on these goals. Any effective treatment aimed at controlling rectal cancer in the pelvis must take into account the disease in the bowel wall itself and the disease, or potential disease, in the mesorectum. The major downside of local excision techniques is the potential of leaving untreated disease in the mesorectum. Local management techniques avoid the potential morbidity, mortality, and functional consequences of a major abdominal radical resection and are thus quite effective in achieving the maintenance of function and quality of life goal. The issue for the transanal techniques is how they fare in achieving the first goal-cure of the cancer while keeping local recurrence rates to an absolute minimum. Without removing both the rectum and the mesorectum there is no completely accurate way to determine whether a rectal cancer has moved outside the bowel wall, so any decision on local management of a rectal neoplasm is a calculated risk. For benign neoplasia, the challenge is removing the lesion without having to resort to a major abdominal procedure.

Long-term follow-up of local rectal cancer surgery by transanal endoscopic microsurgery. World J Surg. 2008;32:1162-1167. [PMID: 18338206 DOI: 10.1007/s00268-008-9512-1]

BACKGROUND

In 1997 we launched a prospective program of transanal endoscopic microsurgery (TEM) for the treatment of rectal cancer.

METHODS

Suitability for TEM was based on endorectal ultrasound results, classified as follows: (I) benign tumors; (II) adenocarcinomas uT0 and uT1 with uN0; (III) adenocarcinomas uT2- uN0, low histological grade with intention to cure; and (IV) advanced stage adenocarcinomas with palliative care

RESULTS

Transanal endoscopic microsurgery was performed in 218 patients: 122 adenomas, and 96 adenocarcinomas: group II-72, group III-19, and group IV-5. Follow-up was >24 months (median 59 months) in 61 patients. Nine were lost to follow-up, and so 52 patients were studied: group II-38, group III-11, and group IV-3. The Kaplan-Meier probability of nonrecurrence of adenocarcinoma by group was 93% in tumors in situ (Tis) and T1; and 77.8% in T2. The Kaplan-Meier probability of survival by group was 100% in Tis and T1 and 82% in T2.

CONCLUSIONS

Rates of recurrence and long-term survival in Tis and T1 adenocarcinomas treated with TEM are similar to those in previously published reports using conventional surgery. Further studies are required in T2 adenocarcinomas to determine a definitive strategy.

Management of early rectal cancer

BACKGROUND

Early rectal cancer (ERC) is adenocarcinoma that has invaded into, but not extended beyond, the submucosa of the rectum (that is a T1 tumour). Local excision is curative for low-risk ERCs but for high-risk cancers such management is controversial.

METHODS

This review is based on published literature obtained by searching the PubMed and Cochrane databases, and the bibliographies of extracted articles.

RESULTS AND CONCLUSION

ERC presents as a focus of malignancy within an adenoma, as a polyp, or as a small ulcerating adenocarcinoma. Preoperative staging relies on endorectal ultrasonography and magnetic resonance imaging. Pathological staging uses the Haggitt and Kikuchi classifications for adenocarcinoma in pedunculated and sessile polyps respectively. Lymph node metastases increase with the Kikuchi level, with a 1-3 per cent risk for submucosal layer (Sm) 1, 8 per cent for Sm2 and 23 per cent for Sm3 lesions. Low-risk ERCs may be treated endoscopically or by a transanal procedure. Transanal excision or transanal endoscopic microsurgery may be inadequate for high-risk ERCs and adjuvant chemoradiotherapy may be appropriate. There is a low rate of recurrence after local surgery for low-risk ERCs but this increases to up to 29 per cent for high-risk cancers.

The Relationship Between MR Demonstration of Extramural Venous Invasion and Nodal Disease in Rectal Cancer

PURPOSE

To investigate the relationship between extramural venous invasion (EMVI) detected at T2-weighted MRI and nodal disease rectal cancer compared with histopathology.

MATERIALS AND METHODS

The MR imaging of 79 consecutive patients with rectal cancer who underwent primary rectal surgery without neoadjuvant treatment were reviewed. MR images were scored by an expert radiologist for the presence and degree of EMVI using a five point scale blinded to pathological findings. Receiver operating characteristic curve analyses were performed to determine the sensitivity and specificity of MRI scoring in predicting EMVI and nodal disease at histopathology.

RESULTS

Compared with histology, an MR score of >2 was found to have 100% sensitivity (95% CI: 77%-100%) and 89% specificity (95% CI: 79%-96%) in identifying EMVI involving veins >3 mm in diameter. An EMVI score of >2 was had a sensitivity of 56% (95% CI: 30%-80%) and specificity of 81% (95% CI: 69%-90%) for identifying patients with stage N2 disease.

CONCLUSIONS

EMVI score of >2 on T2-weighted MR imaging has a high sensitivity and specificity for histopathologically proven extramural venous invasion involving venules ≥3 mm in diameter. However, EMVI scores have only moderate sensitivity in the predicting nodal involvement.

TEM/local excision: indications, techniques, outcomes, and the future

Transanal endoscopic microsurgery (TEM) has emerged as a safe method for excising virtually any rectal adenoma and carefully selected cancers. Extended applications include treatment of extra- and supra-sphincteric fistulae, rectovaginal fistulae, anastomotic strictures, and sinus tracts. The procedure utilizes an air-tight system, long shafted instruments, high-quality magnifying optics, and constant carbon dioxide insufflation, all of which facilitate a precise excision and closure with clear margins. Complications are few, most patients can be treated as an outpatient.

Optimal pathologic staging: defining stage II disease

Tumor stage remains the most important determinant of prognosis in colorectal cancer and is the basis of all authoritative patient management guidelines. The pathologic assessment of stage II disease is especially critical because it may help to identify patients at additional risk for whom surgery alone may not be curative. Accurate analysis of regional lymph nodes, extent of tumor penetration, and circumferential resection margins constitute the most crucial issues. For assignment of pN0, adequacy of the surgical resection and thoroughness of the lymph node harvest from the resection specimen are both essential. The minimum number of lymph nodes has been variably determined to be between 12 and 18 for assignment of pN0, but the confidence level increases with increasing numbers of nodes examined. The ability of exhaustive analysis of sentinel lymph nodes using special techniques to substitute for an exhaustive lymph node harvest and standard node examination has not been definitively shown. Although special techniques may facilitate the identification of minute amounts of tumor (i.e., isolated tumor cells) in regional lymph nodes, the prognostic significance of such findings remains unclear. Additional stage-independent pathologic features that have been validated as adverse prognostic factors include involvement by tumor of mural lymphovascular channels, venous vessels, or the surgical resection margin of the operative specimen and high tumor grade. The presence of these features may help to identify patients for whom surgery alone will not be curative and adjuvant therapies may be appropriate.

Early rectal cancer: local excision or radical surgery?

BACKGROUND

Sphincter preservation, disease control, and long-term survival are the main goals in the treatment of rectal cancer. Although transanal local excision is attractive because it is a sphincter sparing procedure, some contradictory data exist in the literature about its ability to locally control disease and provide overall survival comparable with radical procedures, even for patients with early stage tumor.

PURPOSE

To compare transanal local excision and radical surgery treatment results based on the appropriate data in literature.

METHODS

We reviewed the literature to identify the current recurrence and survival rates of both techniques as well as the salvage surgery success. A PubMed search of the last 10 years was performed, and a total of 10 nonrandomized studies were identified; only 1 study was prospective, 5 were comparative, and 5 were case reports.

RESULTS

Five-year overall survival rate varied from 69% to 83% in the local excision group versus 82% to 90% for the radical excision group. Local recurrence rates ranged from 9% to 20% for local excision and from 2% to 9% for radical surgery. Systemic recurrence rates ranged from 6% to 21% for local excision and from 2% to 9% for radical surgery.

CONCLUSION

Radical surgery is the more definitive cancer treatment; however, it does not eliminate local excision as a reasonable choice for many patients, who will have lesser procedure-related morbidity and will accept an increased risk of tumor recurrence, a prolonged period of postoperative cancer surveillance, and a decreased success rate by salvage surgery.

Nodal staging in rectal cancer

Rectal cancer is common and nodal disease is an independent adverse prognostic factor for patient survival. Accurate demonstration of the presence and location of nodal disease preoperatively may influence management strategies. In this article we review the pathways of nodal spread in rectal cancer and assessment of nodal disease using sonography, CT, and MRI. The use of morphological criteria instead of size criteria has been shown to improve nodal staging by MRI. The potential role of magnetic resonance lymphography and PET imaging in further improving nodal staging accuracy is discussed.

Quality of life after transanal endoscopic microsurgery and total mesorectal excision in early rectal cancer

OBJECTIVE

Total mesorectal excision (TME) is the gold standard in rectal cancer, if curation is intended. Transanal endoscopic microsurgery (TEM) is a much safer technique and seems to have comparable survival in early rectal cancer. The impact of both procedures on quality of life has never been compared. In this study we compared quality of life after TEM and TME.

METHOD

Fifty-four patients underwent TEM for a T1 carcinoma. Only patients without known locoregional or distant recurrences were included, resulting in 36 eligible patients in whom quality of life after TEM was studied. The questionnaires used included the EuroQol EQ-5D, EQ-VAS, EORTC QLQ-C30 and EORTC QLQ-CR38. The results were compared with a sex-and age-matched sample of T+N0 rectal cancer patients who had undergone sphincter saving surgery by TME and a sex- and age matched community-based sample of healthy persons.

RESULTS

Thirty-one patients after TEM returned completed questionnaires (overall response rate 86%). Quality of life was compared with 31 TME patients and 31 healthy controls. From the patients' and social perspective quality of life did not differ between the three groups. Compared with TEM, significant defecation problems were seen after TME (P < 0.05). A trend towards better sexual functioning after TEM, compared with TME, was seen, especially in male patients, although it did not reach statistical significance.

CONCLUSION

Transanal endoscopic microsurgery and TME do not seem to differ in quality of life postoperatively, but defecation disorders are more frequently encountered after TME. This difference could play a role in the choice of surgical therapy in (early) rectal cancer. Further prospective studies are needed to confirm our conclusions.

Prognostic significance of immunohistochemically detected blood and lymphatic vessel invasion in colorectal carcinoma: its impact on prognosis

BACKGROUND

The prognostic significance of blood vessel invasion (BVI) and lymphatic vessel invasion (LVI) is unclear. Because of the absence of specific markers for venous and lymphatic vessels, earlier studies could not reliably distinguish between BVI and LVI.

METHODS

By immunostaining for podoplanin and CD34 antigen, we retrospectively investigated LVI and BVI in 419 tissue specimens of colorectal carcinoma. We performed univariate and multivariate analysis of the clinicopathologic features, frequency of recurrence, and outcome of patients with or without LVI and BVI.

RESULTS

The use of hematoxylin and eosin (H&E) staining to identify BVI and LVI yielded a false positive rate of 9.1% and false negative rate of 12.6%. The incidence of BVI was significantly higher among tumors with LVI than tumors without LVI (P <.001). In logistic multivariate analysis, only LVI (P < .001) was associated with lymph node metastasis and BVI (P = .015) was associated with distant recurrence. Calculating the prognostic relevance, both two invasion types correlated with decreased survival in univariate analysis (both P <.001). In multivariate analysis, BVI (P =.024), lymph node status (P =.003) and tumor stage (P <.001) remained statistically significant factors for survival.

CONCLUSIONS

Our results suggest that immunohistologic evaluation of BVI and LVI could be useful in colorectal carcinoma indicating the risk of lymph node metastasis and recurrence, thereby contributing to prognostic evaluation.

Local recurrence after transanal endoscopic microsurgery for rectal polyps and early cancers

BACKGROUND

Transanal endoscopic microsurgery (TEM) allows for local excision of rectal neoplasms with greater exposure than transanal excision and less morbidity than transabdominal approaches. This study examines the implications of the procedure with respect to predictors of recurrence.

METHODS

We performed a retrospective analysis of 144 consecutive TEMs from 1993 to 2004.

RESULTS

The study comprises 107 patients presenting for TEM with benign disease and 32 patients with cancer. Patients had a mean age of 64+/-14 (SD) years. TEM was performed for recurrent lesions in 17% of cases. Pathologic classification of the lesions after TEM was benign adenoma in 45%, adenoma with high-grade dysplasia (HGD) in 17%, cancer in 33%, and other in 4%. Complications occurred in 10%, and local recurrence occurred in 15% of patients. Median follow-up was 44 months, with a median time to recurrence of 14 months. Positive margins did not influence lesion recurrence. Recurrence of cancers correlated with the depth of tumor invasion (P<.05). On multivariate analysis, independent predictors of recurrence were lesion size and the presence of HGD within adenomas (P<.05). Five-year neoplastic recurrence probabilities were 11% for benign adenomas, 35% for adenomas with HGD, and 20% for cancers (P=.31); invasive recurrence probabilities were 0% for benign adenomas, 15% for adenomas with HGD, and 13% for cancers (P<.05).

CONCLUSIONS

Close endoscopic follow-up is warranted after TEM for both benign and malignant disease, with special attention to lesions with HGD. TEM can be performed safely for early rectal cancer with careful patient selection.

Transanal endoscopic microsurgical resection of pT1 rectal tumors

PURPOSE

Transanal endoscopic microsurgery has emerged as an improved method of transanal excision of neoplasms because its enhanced visibility, superior optics, and longer reach permit a more complete excision and precise closure. This study will show that transanal endoscopic microsurgical treatment of pT1 rectal cancers is safe and achieves low local recurrence and high survival rates.

METHODS

Retrospective review performed of all pT1 rectal cancers treated by a single surgeon (TS) using transanal endoscopic microsurgery between 1991 and 2003. Patient age, gender, tumor distance from the anal verge, lesion size, operative time, blood loss, complications, recurrence, and survival rates were prospectively recorded.

RESULTS

Fifty-three patients (average age, 65.6 (range, 31-89) years) were studied. Forty-nine percent were male. Average tumor distance from the anal verge was 7 (range, 0-13) cm; average size was 2.4 (range, 1-10) cm. Radiation and/or chemotherapy were not administered. Sixteen patients had pT1 lesions removed piecemeal during colonoscopy; there was no residual tumor after transanal endoscopic microsurgical resection of the polyp site. Mean follow-up was 2.84 years. Fifty-one percent had longer than two-year follow-up. For the entire group, there were four recurrences (7.5 percent) occurring at 9 months, 15 months, 16 months, and 11 years. Two were treated with abdominoperineal resection, one with low anterior resection, and one with fulguration alone. There were no recurrences in the 16 patients who had excision of the polypectomy site. If excluded, recurrence was 11 percent (4/37). Patients were examined at three-month intervals for the first two years and every six months thereafter. There have been no cancer-related deaths.

CONCLUSIONS

Transanal endoscopic microsurgical resection of pT1 rectal cancers yields low recurrence rates. Close follow-up permits curative salvage for those that do recur. Transanal excision remains a viable option.

Recurrence after transanal excision of T1 rectal cancer: should we be concerned?

PURPOSE

Transanal excision is an appealing treatment for low rectal cancers because of its low morbidity, mortality, and better functional results than transabdominal procedures. However, controversy exists about whether it compromises the potential for cure. Several, recent reports of high recurrence rates after local excision prompted us to review our results of transanal excision alone in patients with T1 rectal cancers.

METHODS

All patients with T1 low rectal cancer undergoing local excision alone between 1980 through 1998 were reviewed for local recurrence, distant metastasis, disease-free interval, results of salvage surgery, and overall and disease-free survival. Demographics, tumor size, distance from anal verge, and preoperative endoluminal ultrasound results also were recorded. Patients with poorly differentiated tumors, perineural or lymphovascular invasion, or with mucinous component were excluded.

RESULTS

Fifty-two patients underwent transanal excision during the study period. Five-year recurrence was estimated to be 29.38 percent (95 percent confidence interval, 15.39-43.48). For 52 patients, five-year, cancer-specific and overall survival rates were 89 and 75 percent respectively. Fourteen of 15 patients with recurrence underwent salvage treatment with 56.2 percent (95 percent confidence interval, 35.2-90) five-year survival rate. Gender, preoperative staging by endorectal ultrasound, distance from the anal verge, tumor size, location, and T1 status discovered after transanal excision of a villous adenoma did not influence local recurrence or tumor-specific survival.

CONCLUSIONS

Transanal excision for T1 rectal tumors with low-grade malignancy has a high rate of recurrence. Although overall cancer survival rates might be regarded as satisfactory, this high recurrence and low salvage rate raises the issue about the role of transanal excision alone for early rectal cancer and the possible need for adjuvant therapy or increased role of resective surgery.

The clinicopathological significance of inferior mesenteric lymph node metastasis in colorectal cancer

AIMS

There are few studies reporting survival or recurrence patterns in colorectal cancer patients with inferior mesenteric lymph node metastasis (IMLN+). The present study evaluated the prognostic significance of patients being IMLN+ or IMLN- in colorectal cancer.

METHODS

Survival, recurrence pattern and treatment protocols were compared between 63 IMLN+ patients and 108 IMLN- patients with stage III and IV rectal and sigmoid cancer undergoing curative surgery. Lymph node sampling was routinely performed prior to inferior mesenteric artery ligation and excision flush with aorta. Limited principal node dissection including IMLN was performed in cases of identified node metastasis.

RESULTS

The 5-year disease-free survival rates were 50% in IMLN- and 31% in IMLN+ patients (P=0.004). The 5-year disease-free survival rate was greater in the N1 group than the N2 group (P=0.038). Cox regression analysis showed IMLN+, lymphovascular tumour invasion, T4, M1, and pre-operative serum CEA level over 6 ng/ml were independently associated with unfavorable disease-free survival. The prognostic significance of M category was greater when the IMLN+ was included in the M1 as opposed to the N category. In patients undergoing absolute curative surgery, post-operative recurrence rates were 34% for IMLN- and 57% for IMLN+ patients (P=0.009; OR, 2.611; 95% CI, 1.313-5.194). For IMLN+ patients, post-operative adjuvant treatment independently correlated with disease-free survival (P=0.029).

CONCLUSIONS

IMLN+ is an independent survival factor enhancing the prognostic significance of the M category in the AJCC staging. Curative radical surgery and post-operative chemoradiotherapy appears to be warranted for IMLN+ colorectal cancer patients as it resulted in 5-year disease-free survival rates of up to 31% compared to 50% in IMLN- patients.

Impact of Preoperative Staging and Chemoradiation Versus Postoperative Chemoradiation on Outcome in Patients With Rectal Cancer: A Decision Analysis

BACKGROUND

Although radical resection and postoperative chemoradiation have been the standard therapy for patients with rectal cancer, preoperative staging by local imaging and chemoradiation are widely used. We used a decision analysis to compare the two strategies for rectal cancer management.

METHODS

We developed a decision model to compare survival outcomes after postoperative chemoradiation versus preoperative staging and chemoradiation in patients aged 70 years with resectable rectal cancer. In the postoperative chemoradiation strategy, patients undergo radical resection and receive postoperative chemoradiation. In the preoperative staging and chemoradiation strategy, patients with locally advanced cancer receive preoperative chemoradiation and radical resection, whereas those with amenable localized tumors undergo local excision. The cohorts of patients were entered into a Markov model incorporating age-adjusted and disease-specific mortality. Outcomes were evaluated by modeling 5-year disease-specific survival for preoperative chemoradiation as less than, equal to, or greater than that of postoperative chemoradiation. Base-case probabilities were derived from published data; the Surveillance, Epidemiology, and End Results (SEER) Program database; and U.S. Life Tables. One-way and two-way sensitivity analyses were performed. The outcome measures were life expectancy and quality-adjusted life expectancy.

RESULTS

Life expectancy and quality-adjusted life expectancy were 9.72 and 8.72 years, respectively, in the postoperative chemoradiation strategy. In the preoperative staging and chemoradiation strategy, life expectancy was 9.36, 9.72, and 10.09 years and quality-adjusted life expectancy was 8.71, 9.04, and 9.37 years when 5-year disease-specific survival was less than, equal to, or greater than that of postoperative chemoradiation, respectively. The decision model was sensitive to differences in the long-term toxicity of pre- and postoperative chemoradiation. When the 5-year disease-specific survival for patients after pre- or postoperative chemoradiation was equal, the decision model was sensitive to surgical mortality and to the probability of residual lymph node disease after local excision.

CONCLUSION

If efficacy and toxicity after preoperative chemoradiation are equal to or better than that after postoperative chemoradiation in patients with locally advanced rectal cancer, then preoperative staging to select patients appropriate for preoperative chemoradiation is beneficial.

Pathologic prognostic factors in the recurrence of rectal cancer

For rectal cancer, local recurrence following surgical treatment is a grave complication that occurs in as many as 25% of cases. Pathological examination of the surgical resection specimen plays a primary role in assessing both the surgery- and tumor-related factors that contribute to the risk of recurrence. Among the tumor-related factors, stage has long been considered the single most accurate indicator of survival. However, recent evidence strongly suggests that the most powerful predictor of both local recurrence and overall outcome in the absence of distant metastatic disease is the macroscopic quality of the mesorectum in the resection specimen and the proximity of the tumor to the circumferential (radial) resection margin. Additional pathologic features have been shown to have stage-independent prognostic significance in colorectal cancer and may help to further define risk of adverse outcome. Such features include: tumor grade; histologic type; extent of extramural penetration by tumor; neural, venous, and/or lymphatic invasion; tumor border configuration; tumor budding; and host lymphoid response. The predictive value of tumor-specific molecular features is currently under investigation and may help to further improve prognostication and refine individual patient management in rectal cancer.

Venous invasion may predict lymph node metastasis in early rectal cancer

AIM

The aim of this study was to evaluate the role of histopathological and demographic characteristics in predicting lymph node metastasis in patients with adenocarcinoma of the rectum confined to the mucosal and submucosal layers.

METHODS

Fifty-nine patients with early rectal cancer underwent resection of the rectum including lymph nodes and five showed lymph node metastasis (8.6%). Pathology slides of these patients were reviewed by a single pathologist. Demographic and clinical characteristics of these 59 patients were correlated with the existence of nodal metastasis. Formal tests of comparability were carried out by using Fisher's exact test. Logistic regression models were fitted to data to examine possible relationships with 12 covariates measured from each patient and to obtain corresponding odds ratios (as well as a 95% confidence interval for the odds ratios). These covariates included age at surgery, gender, morphology, histology, degree of differentiation, Haggitt's classification for polyps according to the level of invasion, lymphatic and venous invasion, desmoplastic reaction, degree of lymphocytic invasion, presence of lymphoid follicles and presence of infiltrating or pushing margins.

RESULTS

A significantly higher rate of lymph node metastasis occurs in the presence of venous invasion (P < 0.01). Venous invasion was present in three of five (60%) patients with lymph node metastasis and only four of 54 (7%) patients without lymph node metastasis. Other variables did not achieve statistical significance.

CONCLUSIONS

Only the presence of venous invasion was found to be highly significant. The odds ratio of lymph node metastasis increased 18-fold for a patient who had venous invasion compared with a patient who did not. This suggests that the presence of venous invasion in early rectal cancer may provide valuable information to determine which patients would benefit from radical surgery, or adjuvant radiation therapy after sphincter-sparing surgery owing to an increased risk of lymph node metastasis.

Transanal endoscopic microsurgery for rectal cancer

If curation is intended for rectal cancer, total mesorectal excision with autonomic nerve preservation (TME) is the gold standard. Transanal resection is tempting because of low mortality and morbidity rates. However, inferior tumour control, provoked by the limitations of the technique, resulted in its cautious application and use mainly for palliation. Transanal endoscopic microsurgery (TEM) is a minimal invasive technique for the local resection of rectal tumours. It is a one-port system, introduced transanally. An optical system with a 3D-view, 6-fold magnification and resolution as the human eye, together with the creation of a stabile pneumorectum, and specially designed instruments allow full-thickness excision under excellent view and a proper histological examination. The technique can also be applied for larger and more proximal tumours. Mortality, morbidity as well as incomplete excision rates are minimal. Local recurrence and survival rates seem comparable to TME in early rectal cancer. TEM is the method of choice when local resection of rectal cancer is indicated. Results justify a re-evaluation of the indications for the local excision of rectal cancer with a curative intent.

Transanal full-thickness excision of rectal tumours: should the defect be sutured? a randomized controlled trial

PURPOSE: It is generally recommended that the defect, after full thickness total wall excision of a tumour located in the extraperitoneal part of the rectum, should be sutured. There is a lack of controlled studies however, supporting this approach. The aim of this study was to compare the results obtained in patients after peranal local excision of rectal tumours whose defect were sutured with those that were not. METHODS: 44 patients were prospectively randomized to group A: The defect is closed; Group B: Defect left un-sutured. Pre-operative test were digital examination, proctoscopy and endorectal ultrasound. Local full-thickness excision was performed mainly with the Transanal Endoscopic Microsurgery (TEM) equipment, but for cases near the anal verge a Parks' retractor was used. Data recorded were operation time, blood loss, hospital stay and early and late complications. The first postoperative assessment was planned at 1 month and then every three months until 18 months of follow-up. Result for 40 patients (21 from group A; 19 from group B) were analysed. There were no differences between groups regarding age, sex, location of the tumour and specimen's size. RESULTS: The intra-operative loss of blood was 22 ml for group A and 39 ml for B, the difference was not significant. The mean operation time was slighter longer for group A (93 min) than for group B (77 min) but not statistically significant. For both group the mean hospital stay was of 4[2-7] days. No differences in early or late complications could be demonstrated. CONCLUSION: The present study suggests that there is no difference between these two practices in terms of intra-operative results and outcome.

Local excision of rectal cancer: what is the evidence?

PURPOSE

Although local excision of rectal cancers is a less morbid alternative to radical resection, its role as a curative procedure is unclear. The role of adjuvant therapy after local excision is also controversial. This review aims to examine current evidence on local excision of rectal cancers and how it fits into the management algorithm for rectal cancer.

METHODS

A literature review was undertaken through the MEDLINE database and by cross-referencing previous publications, thus identifying 41 studies on curative local excision of rectal cancer published in English. Details of preoperative staging, surgical procedures, adjuvant therapy, follow-up, and outcome measures, including complications, survival data, recurrences, and salvage were examined.

RESULTS

Preoperative staging of rectal cancers is variable. Digital rectal examination and computerized tomography are used in most studies. Endorectal ultrasound is used in some patients in 9 of 41 studies. Local excision preserves anorectal function, and seems to have limited morbidity (0-22 percent). Local excision alone is associated with local recurrences in 9.7 (range, 0-24) percent of T1, 25 (range, 0-67) percent of T2 and 38 (range, 0-100) percent of T3 cancers. The addition of adjuvant chemoradiotherapy after local excision yields local recurrence rates of 9.5 (range, 0-50) percent for T1, 13.6 (range, 0-24) percent for T2, and 13.8 (range, 0-50) percent for T3 cancers. Data on local excision after preoperative chemoradiotherapy for tumor down staging are limited. Factors other than T-stage that lead to higher local recurrence rates after local excision include poor histologic grade, the presence of lymphovascular invasion, and positive margins. Local recurrences after local excision can be surgically salvaged (84 of 114 patients in 15 studies), with a disease-free survival rates between 40 and 100 percent at a follow-up of 0.1 to 13.5 years.

CONCLUSIONS

Local excision for rectal cancers is associated with a low morbidity and provides satisfactory local control and disease-free survival rates for T1 rectal cancers. There is, however, a need for a randomized, controlled trial for T2 cancers, comparing local excision with adjuvant chemoradiotherapy to radical resection.

Factors affecting local control and survival after treatment of carcinoma of the rectum by endocavitary radiation: a retrospective study of 97 cases

PURPOSE

Endocavitary radiation therapy constitutes an alternative to surgical therapy for some early rectal carcinomas. We studied the prognostic factors for locoregional or metastatic relapse after endocavitary radiation, and their impact for therapeutic strategy.

METHODS AND MATERIALS

Our study reports the outcome of 97 patients with adenocarcinomas of the rectum treated from 1978 to 1998 by endocavitary irradiation (100 Gy), exclusive or combined with an interstitial brachytherapy boost of 20 Gy. The indications consisted mostly of polypoid, mobile tumors, less than 4 cm in diameter, and well differentiated. But the indications were extended to elderly patients, who presented with a high surgical risk or who refused mutilating surgery.

RESULTS

The mean follow-up was 82 months. One patient presented with an isolated distant metastatic relapse, and 27 patients presented with locoregional recurrence, surgically salvaged in 16 cases. Disease-free survival was 71% at 5 years and 68% at 10 years. Multifactorial analysis suggests that clinical stage T1A, well-differentiated tumors, and early and complete response are favorable prognostic factors for disease-free survival. Response to therapy is the most powerful prognostic factor for relapse.

CONCLUSION

This retrospective study confirms the efficacy of endocavitary radiotherapy combined with brachytherapy as a safe conservative treatment in well-selected patients.

Surgeon influenced variables in resectional rectal cancer surgery

PURPOSE

Surgeon influenced variables in rectal cancer surgery were assessed.

METHODS

The literature was reviewed to discuss technical and educational issues that may affect the outcome of surgery for rectal cancer. Particular attention was paid to recently debated topics such as adjuvant therapy, colonic J-pouches, total mesorectal excision, and surgeons' training.

RESULTS

In some selected cases, transanal techniques with or without neoadjuvant or adjuvant therapy have improved the success of local excision. The biology of rectal cancer has begun to be understood. However, until a more complete understanding with an appreciation of therapeutic implications has been arrived at, surgeon influenced variables will continue to be of paramount importance. Multiple studies have shown tremendous surgeon variability in the outcome after rectal cancer surgery. Some of the variables that have been shown to be important include tumor-free distal and lateral margins, a total mesorectal excision, and an appropriate anastomosis. It has been well demonstrated that proctectomy with straight coloanal anastomosis compromises function as compared with preoperative levels or healthy controls. These deficiencies are further exacerbated by adjuvant therapy. Significant functional improvements, particularly in the first 12 to 24 months after surgery, have been achieved with use of colonic J-pouch.

CONCLUSION

There are many ways by which the surgeon can optimize curative resection for rectal cancer. Appropriate distal and tumor-free lateral margins with total mesorectal excision should be the goals for all tumors in the lower two-thirds of the rectum. Reconstruction should be performed, whenever technically possible, by a colonic J-pouch. Surgeons should be cognizant of their own practice patterns, volume, capabilities, and very importantly results. These results should be audited frequently and willingly shared with patients.