Number of lymph nodes examined and prognosis of TNM stage II colorectal cancer

Should total number of lymph nodes be used as a quality of care measure for stage III colon cancer?

OBJECTIVE

To assess whether TNODS is an independent prognostic factor after adjusting for the lymph node ratio (LNR).

SUMMARY BACKGROUND DATA

The medical literature has suggested that the TNODS is associated with better survival in stage II and III colon cancer. Thus TNODS was endorsed as a quality measure for patient care by American College of Surgeons, National Quality Forum. There is, however, little biologic rationale to support this linkage.

METHODS

: A total of 24,477 stage III colon cancer patients were identified from Surveillance, Epidemiology, and End Results cancer registry and categorized into 4 groups, LNR1 to LNR4, according to LNR interval: <0.07, 0.07 to 0.25, 0.25 to 0.50, and >0.50. Patients were also stratified according to TNODS into high TNODS (> or = 12) and low TNODS (<12) groups. The method of Kaplan-Meier was used to estimate the 5-year survival and the log-rank test was used to test the survival difference among the different groups.

RESULTS

Patients with high TNODS have better survival compared with those with low TNODS (5-year survival 51.0% vs. 45.0%, P < 0.0001). However, after stratifying by LNR status, there was no significant survival difference between patients with high TNODS and those with low TNODS within strata LNR2 (5-year survival 56.3% vs. 56.0%, P = 0.26). Ironically, patients with high TNODS had significantly worse survival than those with low TNODS within strata LNR3 (5-year survival 41.2% vs. 47.4%, P = 0.0009) and LNR 4 (5-year survival 22.0% vs. 32.1%, P < 0.0001).

CONCLUSIONS

The previously reported prognostic effect of TNODS on node-positive colon cancer was confounded by LNR. This observation calls into question the use of TNODS as a quality measure for colon cancer patients' care.

Reduced lymph node yield in rectal carcinoma specimen after neoadjuvant radiochemotherapy has no prognostic relevance

BACKGROUND

In colorectal surgery UICC/AJCC criteria require a yield of 12 or more locoregional lymph nodes for adequate staging. Neoadjuvant radiochemotherapy for rectal carcinoma reduces the number of lymph nodes in the resection specimen; the prognostic impact of this reduced lymph node yield has not been determined.

METHODS

One hundred two patients with uT3 rectal carcinoma who were receiving neoadjuvant radiochemotherapy were compared with 114 patients with uT3 rectal carcinoma who were receiving primary surgery followed by adjuvant radiochemotherapy. Total lymph node yield and number of tumor-positive lymph nodes were determined and correlated with survival.

RESULTS

After neoadjuvant radiochemotherapy both total lymph node yield (12.9 vs. 21.4, p < 0.0001) and number of tumor-positive lymph nodes (1.0 vs. 2.3, p = 0.014) were significantly lower than after primary surgery plus adjuvant radiochemotherapy. Reduced total lymph node yield in neoadjuvantly treated patients had no prognostic impact, with overall survival of patients with 12 or more lymph nodes the same as that of patients with less than 12 lymph nodes. Overall survival of neoadjuvantly treated patients was significantly influenced by the number of tumor-positive lymph nodes with 5-year-survival rates of 88, 63, and 39% for 0, 1-3, and more than 3 positive lymph nodes (p < 0.0001).

CONCLUSION

The UICC/AJCC criterion of a total lymph node yield of 12 or more should be revised for rectal carcinoma patients.

Factors that influence 12 or more harvested lymph nodes in early-stage colorectal cancer

BACKGROUND

The number of lymph nodes required for accurate staging is a critical component in early-stage (stage A and B) colorectal cancer (CRC). Current guidelines demand at least 12 lymph nodes to be retrieved. Results of previous studies were contradictory in factors, which influenced the number of harvested lymph nodes. This study was designed to determine the factors that influence the number of harvested lymph nodes (> or =12) in early-stage CRC in a single institution.

METHODS

Between 2003 and 2007, data on patients who underwent surgery for early-stage CRC were analyzed retrospectively. Data for a total of 470 patients were collected and all the tumor-bearing specimens were fixed with node identification performed. Several possible factors that influence 12 or more harvested lymph nodes were investigated and classified into four aspects: (1) operating surgeon, (2) examining pathologist, (3) patient (age, sex, and body mass index), and (4) disease (maximal length of tumor, length of specimen, tumor localization, tumor cell differentiation, Dukes stage, type of resection, and type of tumor).

RESULTS

A total of 289 patients (61.5%) with 12 or more harvested lymph nodes and 181 patients (38.5%) with < 12 lymph nodes were analyzed. The results demonstrate that within a single institution the maximal length of tumor, tumor localization, and depth of tumor invasion according to Dukes stage were independent influencing factors of 12 or more harvested lymph nodes. Maximal length of tumor was associated with more harvested lymph nodes (P < 0.001). Neither the operating surgeon nor the examining pathologist had significant influence on the number of harvested lymph nodes.

CONCLUSIONS

The number of harvested lymph nodes was highly variable in patients who underwent resection of early-stage CRC. Neither the operating surgeon nor the examining pathologist had significant influence on the number of harvested lymph nodes. Therefore, from the viewpoint of the surgeons, disease itself is the most important factor influencing the number of harvested lymph nodes.

Clinically important aspects of lymph node assessment in colon cancer

There has been considerable discussion in the literature regarding the importance and validity of lymph node retrieval and lymph node count for patients with colon cancer. In this article we summarize the importance of lymph node resection and assessment in contemporary colon cancer care, key clinical determinants of lymph node assessment, and discuss the role of lymph node assessment as a quality marker in colon cancer care.

lymph node ratio as a prognostic factor in patients with stage III rectal cancer treated with total mesorectal excision followed by chemoradiotherapy

PURPOSE

To investigate the prognostic impact of lymph node ratio (LNR) on survival in the patients with Stage III rectal cancer.

METHODS AND MATERIALS

We retrospectively reviewed the data of 421 consecutive patients who underwent total mesorectal excision followed by chemoradiotherapy for rectal cancer from 1996 to 2006. The 232 patients with positive lymph nodes (LNs) were divided into four groups according to LNR quartiles: LNR <or=0.1 (n = 69), <or=0.2 (n = 49), <or=0.4 (n = 54), and >0.4 (n = 60). The association between LNR and survival was evaluated by the Kaplan-Meier method and multivariate analysis with covariates of prognostic significance in univariate analysis.

RESULTS

The median numbers of examined and positive LNs were 17 and 3, respectively, and the median LNR was 0.20 (range, 0.03-1). There was a strong correlation between the number of positive LNs and LNR (r = 0.724, p < 0.001). After a median follow-up of 53 months (range, 9-138 months), the actuarial overall survival and disease-free survival rates at 5 years were 69% and 56%, respectively. The 5-year survival rate decreased as LNR increased (<or=0.1, 89%; <or=0.2, 67%; <or=0.4, 64%; >0.4, 50%; p < 0.001). Lymph node ratio was also a significant prognostic factor on Cox regression analysis (<or=0.1, hazard ratio [HR] = 1; <or=0.2, HR = 1.3, p = 0.623; <or=0.4, HR = 2.4, p = 0.047; >0.4, HR = 3.7, p = 0.005). Lymph node ratio had a prognostic effect on overall survival in subgroups of patients with N1 (p = 0.032) and N2 (p = 0.034) tumors.

CONCLUSION

Lymph node ratio was the most significant predictor of survival in the patients with Stage III rectal cancer who had undergone postoperative chemoradiation.

Impact of the number of histologically examined lymph nodes on prognosis in colon cancer: a population-based study in the Netherlands

PURPOSE

The impact of the reported number of lymph nodes at pathologic examination of colon specimens on survival was studied.

METHODS

The data of 2,281 patients with localized colon cancer were retrospectively reviewed. The effect of tumor characteristics and surgical and pathologic factors on the number of lymph nodes and examined lymph node numbers on nodal status and survival were analyzed.

RESULTS

The number of examined nodes increased with T stage, left-sided tumors, and mucinous morphology, but decreased with age. The proportion of node-positive patients increased with a larger number of nodes. A high number of examined nodes and high T stage affected nodal status. The five-year overall survival was 51.3 percent for node-positive patients vs. 68.2 percent for node-negative patients. Node-negative patients had a significantly higher five-year crude and relative survival when more lymph nodes were examined. This was not found for the node-positive group and for all patients combined.

CONCLUSIONS

T stage, localization, and patient age were predictive for the number of nodes examined. A higher number of examined nodes was associated with an increase in node positivity. The survival benefit can be explained by stage migration. Eventually this may lead to an overall survival benefit, as more patients are classified as node-positive, and therefore will receive adjuvant therapy.

Lymph node evaluation in early-stage colon cancer

Accurate nodal staging is of crucial importance in patients with nonmetastatic colon cancer, because it affects patient prognosis and delivery of adjuvant chemotherapy. In this article, we review the role of 2 controversial aspects of lymph node staging in colon cancer: the number of lymph nodes evaluated and sentinel lymph node (SLN) biopsy. Although it is clear that the number of lymph nodes assessed correlates with patient survival, the underlying mechanisms are far more uncertain, and thus, more research is warranted to determine whether interventions to increase nodal assessment will lead to improved patient outcomes. Sentinel lymph node biopsy does not appear to have the same advantages in the treatment of patients with colon cancer as in the treatment of patients with breast cancer or melanoma. Also, it might not improve colon cancer staging above standard pathology, and should be restricted to use in research settings.

Total number of resected lymph nodes predicts survival in esophageal cancer

OBJECTIVE

Several population-based studies have shown that the total number of surgically removed lymph nodes is independently associated with overall and disease-free survival in a variety of gastrointestinal cancers. In this retrospective study, the impact of total nodal count on overall survival in esophageal cancer was examined using a single institution surgical database.

METHODS

We conducted a retrospective review of 264 patients with esophageal cancer treated by esophagectomy without neoadjuvant therapy between January 1988 and December 2006. The association between overall survival (the primary endpoint) and the total number of dissected lymph nodes was evaluated using multivariable Cox regression models.

RESULTS

When the total number of resected nodes was examined as a categorical variable based on quartiles (category 1: < or = 16, category 2: 17-25, category 3: 26-40, category 4: > 40) there was a reduced hazard of death with increasing number of examined nodes. Compared with those in category 1, the death hazard was reduced by 34% (P = 0.08), 48% (P = 0.001), and 49% (P = 0.001), respectively, for patients in categories 2, 3, and 4. For node negative patients a significantly reduced hazard was present only when more than 40 nodes were resected (HR = 0.23, P = 0.01). For node positive patients the death hazard was significantly reduced for those in all higher categories compared with those in category 1 (HR = 0.53, 0.39, 0.49; P = 0.03, 0.001, 0.02, respectively).

CONCLUSION

These data support the findings from population based studies in esophageal cancer and other gastrointestinal tumors, suggesting that a higher nodal count favorably influences survival.

Epidemiology and management options for colorectal cancer in children

Colorectal carcinoma (CRC), although primarily a disease of adulthood, accounts for 2% of malignancies in adolescents and has been reported in children as young as 9 months of age. Our knowledge of CRC in pediatrics is based on a handful of case series and case reports. Apart from one small clinical trial, there has been a lack of prospective clinical studies in this age group. Based on these published reports, most CRC in children is sporadic, but it can also arise in the setting of predisposing conditions, such as gastrointestinal polyposis syndromes, nonpolyposis familial cancer syndromes, and inflammatory bowel disease. Despite some similarities to adult disease, CRC in childhood may be intrinsically different biologically, because it differs from adult-onset CRC in several respects. Childhood CRC tends to be diagnosed at an advanced stage, is largely of mucinous histology, and (probably because of these features) tends to have a poorer outcome. As a result of its rarity in children and the lack of prospective pediatric studies, recommendations for therapy are primarily extrapolated from adult clinical trials. A review of pediatric case series in the English literature emphasizes the prognostic significance of stage of disease, as well as extent of surgical resection. As in adults, early detection is critical in an effort to capture the disease at less advanced stages. Complete surgical resection with aggressive lymph node dissection is essential for cure, and neoadjuvant chemotherapy may be used in an effort to render unresectable lesions resectable. Active agents in adults with CRC include fluorouracil, folinic acid (leucovorin), oxaliplatin, and irinotecan. Furthermore, newer targeted therapeutic agents, such as bevacizumab and cetuximab, have added additional efficacy to the standard chemotherapy backbone. Collaborative multi-institutional pediatric clinical trials are needed to evaluate the prognosis, optimal treatment response, and the basic biology of childhood onset CRC.

The impact of lymph node number on survival in patients with lymph node-negative pancreatic cancer

OBJECTIVES

The role of lymph node (LN) dissection for pancreatic cancer remains uncertain, and guidelines for a minimum LN number have not been established. We hypothesized that LN number in node-negative (N0) pancreatic cancer influences survival.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for patients undergoing resection for N0 pancreatic adenocarcinoma between 1988 and 2003. Lymph node number was categorized as 1-10, 11-20, and >20.

RESULTS

In a cohort of 1915 patients, the median LN number was 7 (range 1-57); 1365 (71%) patients had <11 LN. Survival was significantly better in the 11 to 20 compared with the 1-10 group (median, 20 vs 15 months, respectively, P < 0.0001); no difference was observed between the 11-20 and >20 groups (median, 20 vs 23 months, respectively, P = 0.14). Multivariate analysis demonstrated the prognostic significance of LN number for determining overall survival (hazard ratio 0.98, 95% confidence interval: 0.97-0.99; P<0.0001).

CONCLUSIONS

Pancreatic cancer lymphadenectomy with examination of >10 LN is associated with improved survival in N0 disease and should be considered a benchmark for adequacy of surgery and/or pathology. Currently, only a minority of patients are assessed by this measure. The variation in LN number may be indicative of diverse surgical technique and/or pathologic analysis and warrants further investigation.

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.

The validity of the Royal College of Pathologists' colorectal cancer minimum dataset within a population

Quality of colorectal cancer pathology reports is related to individual patient prognosis and future treatment options. This study sought to validate the prognostic utility of the Royal College of Pathologists minimum pathology dataset (MPD), regarded as the ‘gold standard’, within a population. Retrospective study of the survival of 5947 surgically resected colorectal cancer patients for whom an MPD had been collected. Variables were related to survival. The study population was representative of the Yorkshire colorectal cancer population. Survival was poorer in older patients and colonic tumours and improved over the study period. Local invasion, total number of lymph nodes retrieved, nodal stage, extramural vascular invasion, peritoneal involvement, distance of invasion beyond the muscularis propria, and in rectal cancers, circumferential resection margin involvement and distance to this margin were all validated as of prognostic significance within a population. Failure to report extramural vascular invasion, peritoneal involvement or circumferential resection margin status was associated with a worse survival than absence of the factor. All variables within the Royal College of Pathologists MPD are of prognostic significance. High-quality pathology reports are essential in providing accurate prognostic information and guiding optimal patient management.

Matrix metalloproteinase-9-1562C>T polymorphism may increase the risk of lymphatic metastasis of colorectal cancer

AIM: To explore the role of the matrix metalloproteinase-9 (MMP-9) polymorphism in colorectal cancer (CRC) in a northeast Chinese population.

METHODS: Genotyping of MMP-9-1562C>T and 279R>Q polymorphisms was carried out on blood samples from 137 colorectal cancer patients and 199 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Multivariate logistic regression models were used to calculate adjusted odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS: The distribution of MMP-9 -1562C>T and 279 R>Q genotype was not significantly associated with the risk of CRC. However, the risk of llymph node metastasis of CRC was increased in patients with the -1562T allele (OR = 2.601; 95% CI = 1.160-5.835; P = 0.022). The frequency of MMP-9 279RR + RQ genotype was higher than the QQ genotype among CRC patients younger than sixty years old (OR = 0.102; 95% CI = 0.013-0.812; P = 0.012).

CONCLUSION: Our results indicated that the MMP-9-1562C>T polymorphism affects lymph node metastasis of CRC. In addition, the MMP-9 279R allele may lead to a younger age of onset of colorectal cancer.

Stage migration in colorectal cancer related to improved lymph node assessment

AIM

The aim of the study was to evaluate the clinical impact of improved cooperation between the treating surgeons and pathologists in a high volume surgical unit. As a measure we used the staging process with special focus on lymph node assessment.

FINDINGS

Comparing two periods 5 years apart, we found a significant increase in the number of nodes examined and also an increase in the number of metastasis-positive nodes. Concurrently, we observed a trend in stage migration from stage I/II towards stage III, whilst stage IV remained unchanged. This was one factor that contributed to an increase in the number of patients treated with adjuvant chemotherapy. We also found that the number of assessed nodes had an impact on survival in stage II. The major change in practise was the implementation of a multidisciplinary team conference and the associated possibility of reciprocal feedback.

CONCLUSION

Lymph node status has a key role in cancer staging and in the selection of further therapy. The quality and the standard of the assessment can be improved through multidisciplinary cooperation and it has an impact on the clinical decisions and can affect long-term survival. A correct node status should be mandatory in the evaluation of prognostic factors.

Young age influences treatment but not outcome of colon cancer

BACKGROUND

Early age at onset is often considered a poor prognostic factor for colon cancer. The aim of this study was to determine the association between age, clinicopathologic features, adjuvant therapy, and outcomes following colon cancer resection.

METHODS

A prospective database of 1,327 surgical stage I-III colon cancer patients operated on from 1990-2001 was evaluated, and patients grouped by age.

RESULTS

Sixty-eight patients (5%) were diagnosed at age <or=40 years (younger) compared with 1,259 patients diagnosed at age >40 (older). Younger patients were more likely to have left-sided tumors (66% vs 51%, P = .02), but no more likely to present with symptomatic lesions, more advanced tumors, or have worse pathologic features. Younger patients were noted to have more nodes retrieved in their surgical specimens than older patients (median 18 vs 14, P = .001), although the numbers of total colectomies were similar in both groups. Younger patients were also more likely to receive adjuvant chemotherapy, and this was most pronounced in the stage II cohort: 39% vs 14%, P = .003. With a median follow-up of 55 months, 5-year disease-specific survival (DSS) was similar in both study groups: 86% vs 87%, but 5-year overall survival (OS) was significantly higher in the younger patient cohort (84% vs 73%, P = .001).

CONCLUSION

Younger patients undergoing complete resection of stage I-III colon cancer had DSS similar to older patients. However, younger patients had more nodes retrieved from their specimens and were more likely to receive adjuvant therapy, especially for node-negative disease. These factors may have contributed to their overall favorable outcome.

Identifying Stage III Colorectal Cancer Patients: The Influence of the Patient, Surgeon, and Pathologist

Purpose

Nodal yields from resected colorectal cancers vary greatly. This study sought to determine what patient, tumor, and management factors influence the number of nodes retrieved and to determine if the extent of lymphadenectomy affects stage allocation and influences survival.

Patients and Methods

Retrospective study of the nodal yields of 7,062 surgically resected colorectal cancer patients for whom colorectal pathology minimum data sets had been collected. The percentage of patients diagnosed as stage III was compared across nodal yield categories. A threshold for an adequate lymphadenectomy was defined as retrieval of 12 nodes. Binary logistic regression was used to determine factors associated with obtaining an adequate lymphadenectomy.

Results

Median nodal yields increased over the study period from 7 (interquartile range [IQR], 4 to 11) in 1995 to 13 (IQR 8 to 19) in 2003. There was no difference in yield by cancer site or sex, but yields were lower in older patients. Yields increased with increasing local invasion and stage of tumor. The percentage of patients diagnosed as stage III increased as yields increased. Five-year survival was lower in those patients who did not have an adequate lymphadenectomy. Adequate lymphadenectomy was significantly more likely in patients with advanced tumors and when the surgery and pathology was undertaken by a specialist. Older patients were significantly less likely to receive an adequate lymphadenectomy.

Conclusion

Variations in nodal yield are due to idiosyncratic patient and tumor characteristics and differences in the quality of surgery and pathology undertaken. Adequate lymphadenectomy is essential to ensure correct stage allocation and optimal survival.

The prognostic significance of total lymph node harvest in patients with T2-4N0M0 colorectal cancer

In patients with radically resected colorectal carcinoma, lymph node involvement is particularly important for a good prognosis and adjuvant therapy. The number of such lymph node recoveries is still controversial, with recommendations ranging from 6 to 17 nodes. The aim of this study is to determine if a specified minimum number of lymph nodes examined per surgical specimen can have any effect on the prognosis of patients who have undergone curative resection for T(2-4)N(0)M(0) colorectal carcinoma. Between September 1999 and January 2005, a total of 366 patients who underwent radical resection for T(2-4)N(0)M(0) colorectal carcinoma were retrospectively analyzed in a single institution. All specimen segments were fixed, with node identification performed by sight and palpation. We excluded 186 patients who received postoperative adjuvant chemotherapy via oral or intravenous transmission to prevent possible chemotherapeutic effects on patients' prognosis; therefore, a total of 180 patients with T(2-4)N(0)M(0) colorectal carcinoma were enrolled into this study. After the pathological examination, a mean of 12 lymph nodes (range 0-66) was harvested per tumor specimen. No postoperative relapse was found in this group, where the number of examined lymph nodes was 18 or more. Univariate analysis identified the size of the tumor, depth of invasion, grade of tumor, and number of examined lymph nodes, which were significantly correlated with postoperative relapse (all P < 0.05). Meanwhile, both the depth of tumor invasion and the number of harvested lymph nodes were independent predictors for postoperative relapse (P < 0.05). The 5-year overall survival rate of T(2-4)N(0)M(0) colorectal carcinoma patients who had 18 or more lymph nodes examined was significantly higher than those who had less than 18 nodes examined (P = 0.015). Nodal harvest in patients undergoing radical resection for colorectal carcinoma was highly significant in the current investigation. Our results suggest that harvesting and examining a minimum of 18 lymph nodes per surgical specimen might be taken into consideration for more reliable staging of lymph node-negative colorectal carcinoma.

Lymph node evaluation and survival after curative resection of colon cancer: systematic review

BACKGROUND

Adequate lymph node evaluation for cancer involvement is important for prognosis and treatment of patients with colon cancer. The number of lymph nodes evaluated may be a measure of quality in colon cancer care and appears to be inadequate in most patients treated for colon cancer. We performed a systematic review of the evidence for the association between lymph node evaluation and oncologic outcomes in patients with colon cancer.

METHODS

Medline, Scopus, Cochrane, and the National Guidelines Clearinghouse databases were searched from January 1, 1990, through June 30, 2006, for studies in which survival data as a function of number of lymph nodes evaluated were available. These studies were evaluated for methodologic quality, design, and data source. A total of 61,371 patients were included.

RESULTS

Seventeen studies from nine countries were eligible for systematic review, including two secondary analyses of multicenter randomized trials of adjuvant chemotherapy for colon cancer, five population-based observational studies, and 10 single-institution retrospective cohort studies. Despite heterogeneity in methodology and differences in threshold numbers of lymph nodes evaluated (range = 6-40 lymph nodes), 16 of 17 studies reported that increased survival of patients with stage II colon cancer was associated with increased numbers of lymph nodes evaluated. Four of six studies with data from stage III patients also reported a positive association with survival among patients with stage III colon cancer.

CONCLUSIONS

The number of lymph nodes evaluated after surgical resection was positively associated with survival of patients with stage II and stage III colon cancer. These results support consideration of the number of lymph nodes evaluated as a measure of the quality of colon cancer care.

Recommendations for the reporting of surgically resected specimens of colorectal carcinoma

The reporting of colorectal cancer is facilitated by the provision of a checklist giving the features required for good patient care. However, the practicalities of applying such a checklist may not be straightforward. Familiar examples include finding the prescribed number of lymph nodes, distinguishing mesenteric tumor deposits from replaced lymph nodes, and deciding if a cluster of malignant cells in a lymph node sinus counts as metastasis. Checklists have traditionally focused on prognostic factors and, particularly, tumor stage. It is becoming increasingly clear that additional factors, whether morphological or molecular, will be needed for future clinical management. It is also evident that prognosis is strongly influenced by the surgical technique used, most notably by the introduction of total mesorectal excision in the case of rectal cancer. Adjuvant therapy is playing an increasingly important role in the management of colorectal cancer, and it is inevitable that morphological and molecular markers will be used to predict responses to the expanding range of therapeutic modalities. Neoadjuvant or preoperative radiotherapy is being offered to patients with advanced rectal cancer and can greatly modify the pathologic findings in operative specimens. For all the preceding reasons, the work of diagnostic pathologists has become increasingly complex and demanding. The 6th edition of the TNM classification fails to meet many of the challenges posed by the realities of modern cancer management. In fact, by changing the rules for staging without strong justification and introducing diagnostic criteria that are unhelpful and lack a good evidence base, there is a real danger that the community of pathologists will fail to engage with reporting recommendations in a standardized manner and that the quality of reporting will decline.

Potential pathological understaging of pT3 rectal cancer with less than 26 lymph nodes recovered: a prospective study based on a resampling of 50 rectal specimens

The aim of the paper was to establish if the 12 lymph nodes recommended by tumor-node-metastasis (TNM) system are sufficient for a correct staging of rectal cancer. For this purpose, we first compared the mean number of lymph nodes recovered in the same surgical specimen at the routine sampling and at a resampling performed by a second expert gastrointestinal pathologist. The study was performed on 50 cases of pT2N0 and pT3N0 rectal cancers, with a minimum number of 12 lymph nodes recovered at first sampling, histologically negative for metastases. Resampling retrieved a variable number (1 to 24) of nodes missed at first sampling. The final pN0 status was maintained in pT2 patients, whereas in 18.7% of pT3 patients, metastatic lymph nodes were detected if the mean number of lymph nodes increased from 17.8 to 26.8 after the second sampling. Interestingly, all pN1 patients had only a single metastatic lymph node measuring less than 4.9 mm. As we have shown that most (five out of six) missed metastatic lymph nodes were detected in specimens in which a maximum number of 19 lymph nodes had been originally recovered, we strongly suggest a resampling of pT3N0 rectal specimens if less than 20 lymph nodes have been recovered.

Number of Lymph Nodes Examined and its Impact on Colorectal Cancer Staging

The status of lymph nodes is the most important prognosticator in colorectal cancer patients. Patients with lymph node involvement have a lower survival rate and are candidates for adjuvant therapy. The purpose of our study was to determine the number of lymph nodes that needs to be examined to accurately detect nodal metastasis. We conducted a retrospective study of 151 patients who underwent colorectal cancer operation at Harbor-UCLA Medical Center. Data from the operative report and pathology report were collected and analyzed. Fourteen (33.3%) patients with five to nine nodes examined had positive nodes. Twenty-six (57.8%) patients with 10 to 14 nodes examined had positive nodes. Patients who had 10 to 14 nodes examined were significantly more likely to have positive lymph nodes (P = 0.03). Patients with advanced T stage had a significantly higher number of positive lymph nodes (78.1% in T4 vs 11.1% in T1, P < 0.0001). Patients with poorly differentiated cancer showed a trend toward a higher positive node rate. Tumor differentiation and T stage seem to correlate with higher nodal metastasis rate. A higher number of lymph nodes examined was associated with a higher nodal metastasis rate. Examination of at least 10 lymph nodes would increase the yield of positive lymph nodes and avoid under-staging of patients with colorectal cancer.

The ratio of metastatic/resected lymph nodes is an independent prognostic factor in patients with node-positive pancreatic head cancer

OBJECTIVES

The aim of this study was to evaluate the prognostic value of nodal involvement in resected adenocarcinoma of the pancreatic head.

METHODS

For the period between 1980 and 2002, 96 patients underwent pancreaticoduodenectomy for pancreatic cancer. Lymph nodes were numbered and classified into groups according to the Japan Pancreatic Society rules. Metastatic lymph nodes were identified based on hematoxylin and eosin staining.

RESULTS

Sixty-four (66.7%) patients had positive lymph nodes. The median number of metastatic nodes was 2 (95% confidence interval [CI], 1.0-3.0) and the median ratio of metastatic/resected nodes was 9.7% (95% CI, 7.1%-14.4%). The median survival was 14.2 months (95% CI, 10.7-17.7) and was significantly higher for node-negative than node-positive patients (27.9; 95% CI, 20.9-34.9 vs. 10.6; 95% CI, 8.7-12.5; P < 0.001). The Cox proportional hazards model, including all patients, demonstrated that nodal involvement (hazard ratio [HR], 1.461; 95% CI, 1.177-12.024), moderate or poor tumor differentiation (HR, 2.330; 95% CI, 1.181-6.949), and positive resection margins (HR, 3.838; 95% CI, 1.390-10.597) were independent negative prognostic factors. If the analysis was limited to node-positive patients, lymph node ratio of more than 20% (HR, 1.364; 95% CI, 1.116-2.599), moderate or poor tumor differentiation (HR, 3.393; 95% CI, 1.041-11.061), and positive resection margins (HR, 9.400; 95% CI, 2.235-39.536) significantly correlated with a poorer survival.

CONCLUSIONS

Lymph node ratio seems to be a new promising prognostic factor in patients with respectable node-positive pancreatic head cancer.

Pathology practice patterns affect lymph node evaluation and outcome of colon cancer: a population-based study

BACKGROUND

A large variation in the number of nodes examined between patients, hospitals, and regions has been reported for patients with colon cancer. We studied determinants of this variation and its relation to survival in the south of The Netherlands.

PATIENTS AND METHODS

All patients who underwent resection for stage I-III colon carcinoma diagnosed from 1999 to 2002 in the Eindhoven Cancer Registry area were included (n = 2168). Determinants of lymph node evaluation and their relationship to survival were assessed, including variation between the six departments of pathology.

RESULTS

A median number of six lymph nodes per specimen had been examined. The median number for each department of pathology ranged from three to eight (P < 0.0001). After correction for relevant factors, this variation remained, resulting in differences in the proportion of N+ tumours between departments from 29% to 41% (P < 0.0001). The number of nodes examined was positively associated with survival. Survival for node-negative patients differed between the departments of pathology (up to hazard ratio 1.5; P = 0.02).

CONCLUSION

There was a large variation in lymph node evaluation between the departments of pathology, leading to differences in stage distribution and survival. Intervention strategies should be directed at nodal assessment.

Increasing negative lymph node count is independently associated with improved long-term survival in stage IIIB and IIIC colon cancer

PURPOSE

The purpose of this study was to examine the impact of the number of negative lymph nodes on survival in patients with stage III colon cancer.

PATIENTS AND METHODS

Patients who underwent surgery for stage III colon cancer between January 1988 and December 1997 were identified from the Surveillance, Epidemiology and End Results cancer registry. The number of negative and positive nodes was determined for 20,702 eligible patients. Disease-specific survival was examined by substage according to the number of negative nodes identified. A proportional hazards model was constructed to determine the effect of the number of negative nodes on survival.

RESULTS

For stage IIIB and IIIC patients, there was a significant decrease in disease-specific mortality as the number of negative nodes increased; cumulative 5-year cancer mortality was 27% in stage IIIB patients with 13 or more negative nodes identified versus 45% in those with three or fewer negative lymph nodes evaluated (P < .0001). In patients with stage IIIC cancer, those with 13 or more negative nodes had a 5-year mortality of 42% versus 65% in those with three or fewer negative lymph nodes evaluated (P < .0001). There was no association between the number of negative nodes identified and disease-specific survival for patients with stage IIIA disease. After controlling for the number of positive nodes, a higher number of negative nodes was found to be independently associated with improved disease-specific survival.

CONCLUSION

The number of negative nodes is an important independent prognostic factor for patients with stage IIIB and IIIC colon cancer.

The importance of accurate pathological assessment of lymph node involvement in colorectal cancer

This review presents an up-to-date analysis of the importance of accurate pathological lymph node staging in colorectal cancer. Lymph node staging is reliant on the technique of the surgeon and the pathologist as well as methods employed in the histopathology laboratory, and is vital for determining appropriate therapy. The significance of micrometastatic nodal disease is evaluated and new techniques for pathological evaluation are discussed. Recommendations for evaluation of lymph node status in colorectal cancer are provided based on current scientific evidence, and standardization of pathological dissection and laboratory handling is advocated.

Lymph node retrieval in abdominoperineal surgical specimen is radiation time-dependent

BACKGROUND

A low yield of lymph nodes (LN) in abdominoperineal resection (APR) specimen has been associated with preoperative radiation therapy (XRT) in population-based studies, which may preclude adequate staging of anorectal carcinomas. We hypothesized that the number of LN retrieved in APR specimen was correlated with the dose and the timing of pelvic irradiation.

PATIENTS AND METHODS

We performed a retrospective study of 102 patients who underwent APR in a single institution between 1980 and 2004. Pathological reports were reviewed and the number of lymph nodes retrieved in APR specimens was correlated with: 1) Preoperative radiation; 2) Dose of pelvic irradiation; and 3) Time interval between the end of XRT and surgery.

RESULTS

There were 61 men and 41 women, with a median age of 66 (range 25-89) years. There were 12 patients operated for squamous cell carcinoma of the anal canal (SCCA) and 90 for rectal cancer. 83% and 46% of patients with anal and rectal cancer respectively underwent radical/neoadjuvant radiotherapy. The mean +/- SD number of LN in APR specimen was 9.2 +/- 5.9. The mean number of LN in APR specimen was significantly lower in patients who underwent preoperative XRT (8 +/- 5.5 vs. 10.5 +/- 6.1, Mann-Whitney U test, p = 0.02). The mean number of LN was not significantly different after XRT in patients with SCCA than in patients with rectal cancer (6.2 +/- 5.3 vs. 7.8 +/- 5.3, p = 0.33). Finally, there was an inverse correlation between the yield of LN and the time elapsed between XRT and surgery (linear regression coefficient r = -0.32, p = 0.03).

CONCLUSION

Our data indicate that: 1) radiation therapy affects the yield of LN retrieval in APR specimen; 2) this impact is time-dependent. These findings have important implications with regard to anatomic-pathological staging of anal and rectal cancers and subsequent decision-making regarding adjuvant chemotherapy.

Asymptomatic familial colon cancer with FDG-PET scanning for recurrent disease

A 57-yr-old female was referred for screening colonoscopy because of a positive family history of colon cancer. A lobulated tumor mass was detected in the sigmoid colon. The resected specimen showed an invasive adenocarcinoma without lymph node involvement. Later colonoscopic evaluations and CT imaging failed to reveal definite evidence of recurrent disease but a late rising carcinoembryonic antigen level led to FDG-PET scanning and the detection of suspect lymph nodes in the retroperitoneum. Further histopathological and immunohistochemical evaluation of resected lymph nodes confirmed metastatic carcinoma from the primary colon carcinoma with extra-nodal spread. This case underscores the ongoing need for additional evidence-based studies on evolving imaging modalities used in the diagnosis and management of colonic cancer.

Mixed adherence to clinical practice guidelines for colorectal cancer in the Southern Netherlands in 2002

AIMS

Population-based cancer registries can provide excellent data for insight in disease management practice. This study examines the extent to which the consensus-based national clinical guidelines (version 2000-2001) for colorectal cancer (CRC) had been implemented in the diagnostic and treatment approach in the Southern Netherlands in 2002.

METHODS

Data were gathered from the medical records for a random sample from the Eindhoven Cancer Registry of 308 patients with colorectal cancer. Adherence to clinical guidelines was determined for diagnostic assessment, pathology, and treatment during the first year after diagnosis.

RESULTS

Surgical procedures and referral for pre-operative radiotherapy were carried out largely conform the recommendations. The number of performed colonoscopies among colon cancer patients amounted to 60%; contrast enemas after incomplete colonoscopy were performed in only 27% of patients. The median number of examined lymph nodes was only six for patients with colon and five for patients with rectal cancer; the administration of adjuvant chemotherapy for patients with stage III colon cancer decreased from 95% of patients younger than 70 years to 48% of patients over 70.

CONCLUSIONS

Adherence to clinical guidelines was not optimal. Feedback to surgeons and pathologists should improve adherence, especially with respect to nodal retrieval and assessment.