The detection of cytokeratins in lymph nodes of Duke's B colorectal cancer subjects predicts a poor outcome

OBJECTIVES: The objectives of this study were to examine the frequency of lymph node micrometastases detected by keratin immunohistochemistry and their relationship with survival behaviour. METHODS: A total of 133 consecutive patients staged as Duke's B, who had curative resection for colorectal cancer (CRC), comprised the study population. Patients who had died of a non-CRC-related cause or who became lost to follow-up were excluded, resulting in an amended population of 100. Study end-points were defined as disease-free survival of 5 years or CRC-related death. Paraffin-embedded lymph node sections were stained with a commercial cytokeratin antibody using a standard avidin-biotin technique. RESULTS: One quarter of subjects had micrometastases. Fifty-six per cent of subjects with positive lymph nodes had an adverse outcome, compared with 11% of subjects with negative nodes. A highly significant association was found between lymph node cytokeratin expression and mortality in both the univariate (log rank P = 0.0001) and multivariate (Cox proportional hazards P = 0.0123) analysis. CONCLUSIONS: Lymph node micrometastases detected by this inexpensive and simple technique are significantly associated with mortality in Duke's B CRC. This technique may be used to select patients for adjuvant chemotherapy.     

Routine modified D2 lymphadenectomy performance in pT1-T2N0 gastric cancer

AIM: To evaluate routine modified D2 lymphadenectomy in gastric cancer, based on immunohistochemically detected skip micrometastases in level Ⅱ lymph nodes.METHODS: Among 95 gastric cancer patients who were routinely submitted to curative modified D2 lymphadenectomy, from January 2004 to December 2008, 32 were classified as pN0. All level Ⅰ lymph nodes of these 32 patients were submitted to immunohistochemistry for micrometastases detection.Patients in whom micrometastases were detected in the level Ⅰ lymph node stations ( n = 4) were excluded from further analysis. The level Ⅱ lymph nodes of the remaining 28 patients were studied immunohistochemically for micrometastases detection and constitute the material of the present study.RESULTS: Skip micrometastases in the level Ⅱ lymph nodes were detected in 14% (4 out of 28) of the patients.The incidence was further increased to 17% (4 out of 24) in the subgroup of T12 gastric cancer patients. All micrometastases were detected in the No. 7 lymph node station. Thus, the disease was upstaged from stage ⅠA to ⅠB in one patient and from stage ⅠB to Ⅱ in three patients.CONCLUSION: In gastric cancer, true R0 resection may not be achieved without modified D2 lymphadenectomy.Until D2+/D3 lymphadenectomy becomes standard,modified D2 lymphadenectomy should be performed routinely.     

Increased expression of CD133 is a strong predictor of poor outcome in stage I colorectal cancer patients

Abstract Objective. Stage I colorectal carcinomas display a highly variable behavior which is not accurately predicted by the available prognostic markers. CD133 is considered a useful marker to identify the so-called cancer stem cells in colorectal cancers (CRCs) and its expression has been shown to have prognostic significance in CRC patients. This study aimed to verify whether immunohistochemical evaluation of CD133 might correlate with the progression risk of stage I CRC patients. Material and methods. Expression levels of the CD133 molecule were analyzed and compared in two series of stage I surgically resected CRC patients showing disease progression and death for the disease and patients with no evidence of disease progression after at least 6 years after surgery. Results. A positive staining for CD133 was detected in 52% of the cases with poor prognosis and only in 9% of the group with good prognosis, and this difference was highly significant (p < 0.001). A significant correlation was detected between CD133 expression and histological parameters, such as tumor budding, vascular invasion, and presence of lymph node micrometastases but not tumor grading, gender, and age. Disease-free survival and cancer-specific survival of CD133 negative tumors were significantly longer compared to positive cases. In multivariate analyses, CD133 staining confirmed to be a predictor of shorter survival independent from vascular invasion but not from lymph nodes micrometastases. Conclusions. These findings demonstrate that CD133 immunostaining is a useful predictor of high risk progression in stage I CRC patients and might help to identify patients eligible for adjuvant chemotherapy.     

Are lymph node micrometastases of any clinical significance in dukes stages A and B colorectal cancer?

PURPOSE: The aim was to investigate the significance of lymph node micrometastases in Dukes Stages A and B colorectal cancer. METHODS: Archival specimens were examined from 147 patients (96 colon, 51 rectum; 44 Stage A, 103 Stage B) who had surgery between 1987 and 1994. One lymph node section from each node (colon, 1–11; median, 4; rectum, 1–15; median, 3) was examined with use of an anticytokeratin antibody. RESULTS: Forty-seven (32 percent) patients had micrometastases. At follow-up in June 1996, 23 patients had died of cancer or with known tumor relapse, after a median time of 28 (range, 5–67) months; 8 of 47 (17 percent) patients had micrometastases, 15 of 100 (15 percent) did not. No statistically significant differences were observed according to micrometastases when the results were analyzed with respect to Dukes stage or survival time. The median survival time of living patients with micrometastases was 48 (range, 18–97) months, and for patients without micrometastases, 48 (range, 19–111) months. Six of 96 living patients had a tumor relapse; three of these displayed micrometastases. CONCLUSION: Lymph node micrometastases are not a useful prognostic marker in Dukes Stages A and B and do not imply different strategies for additional therapy or follow-up.This study was supported by the Swedish Cancer Foundation (Project No 2520-B96-10XCC, Project No 3453-B97-05XBB).Read at the Second Surgical Week, Västerås, Sweden, August 18 to 22, 1997.     

Analysis of micrometastatic disease in histologically negative lymph nodes of patients with adenocarcinoma of the distal esophagus or gastric cardia

SUMMARY. Lymphatic dissemination is the most important prognostic factor in patients with esophageal carcinoma. However, the clinical significance of lymph node micrometastases is still debated due to contradictory results. The aim of the present study was to identify the incidence of potentially relevant micrometastatic disease in patients with histologically node‐negative esophageal adenocarcinoma and to analyze the sensitivity and specificity of three different immunohistochemical assays. From a consecutive series of 79 patients who underwent a transthoracic resection with extended 2‐field lymphadenectomy, all 20 patients with pN0 esophageal adenocarcinoma were included in this study. A total of 578 lymph nodes were examined for the presence of micrometastases by immunohistochemical analysis with the antibodies Ber‐EP4, AE1/AE3 and CAM 5.2. Lymph node micrometastases were detected in five of the 20 patients (25%). They were identified in 16 of the 578 lymph nodes examined (2.8%) and most frequently detected with the Ber‐EP4 and AE1/AE3 antibody (sensitivity 95% and 79% respectively). In 114 of the 559 negative lymph nodes (20.4%), positive single cells were found that did not demonstrate malignant characteristics. These false‐positive cells were more frequently found with the AE1/AE3 staining (specificity of the Ber‐Ep4 and AE1/AE3 antibody 94% and 84% respectively). The presence of nodal micrometastases was associated with the development of locoregional recurrences (P=0.01), distant metastases (P=0.01), and a reduced overall survival (log rank test, P=0.009). For the detection of clinically relevant micrometastatic disease in patients operated upon for adenocarcinoma of the distal esophagus or gastric cardia, Ber‐EP4 is the antibody of first choice because of its high sensitivity and specificity. Immunohistochemically detected micrometastases in histologically negative lymph nodes have potential prognostic significance and are associated with a high incidence of both locoregional and systemic recurrence. Therefore, this technique has the potential to refine the staging system for esophageal cancer and to help identify patients who will not be cured by surgery alone.     

Histopathological and genetic differences between polypoid and non-polypoid submucosal colorectal carcinoma

AIM： To investigate the histopathological and geneticdifferences between polypoid growth （PG） and nonpolypoid growth （NPG） submucosal invasive colorectal carcinoma （CRC）.
METHODS： A total of 96 cases of submucosal CRC were divided into two groups according to their growth type;60 cases of PG and 36 cases of NPG. The size, histological degree of dysplasia, depth of submucosal invasion and lymph node metastasis were compared between the two groups. Furthermore, expression of p53 was detected by immunohistochemical staining, and K-ras gene mutation was examined by polymerase chain reaction based single-strand conformation polymorphism （SSCP）.
RESULTS： The average size of the lesions in the NPG group was significantly smaller than those in the PG group （7.5 mm vs 13.8 mm, P 〈 0.001）. The histological degree of dysplasia tended to be more severe in NPG group, while the incidence of submucosal massive invasion and the lymph node metastasis were both significantly higher in the NPG type than in the PG group （64.3% vs 43.3%, P = 0.004; 43% vs 7%, P =0.008, respectively）. In addition, K-ras gene mutations were detected in 67% of lesions in the PG group, but none in the NPG group, while no difference in p53immunohistochemical expression was found between the two groups.
CONCLUSION： Compared with PG submucosal CRC,NPG type demonstrates more frequent submucosal massive invasion, more lymph node metastasis and a higher degree dysplasia. Genetically, NPG type shows much less frequent K-ras mutation.     

Detection of Lymphatic Micrometastases in Patients With Stages I and II Colorectal Cancer: Impact on Five-Year Survival

PURPOSE: Despite having removed the whole macroscopic disease (curative intent surgery), one of five patients with Stages I and II colorectal cancer will develop recurrence. Lymphatic micrometastases detected by immunohistochemistry could be one of explanation for recurrence and cancer-related death in patients without lymph node involvement at light microscopy. However, the biologic importance of micrometastases remains unclear. This study was designed to determine the impact of micrometastases in five-year survival in patients with Stages I and II colorectal cancer.METHODS: This retrospective study included patients operated on between May 1989 and January 1999 for colorectal cancer without histopathologic lymph node involvement. Patients who received any adjuvant therapy were excluded. Immunohistochemical staining of the lymph nodes was performed with antipancytokeratin antibodies. Follow-up data were obtained from the clinical database and death certificates. Survival was estimated by the Kaplan-Meier method and compared by the log-rank test.RESULTS: Micrometastases were observed in 26 of 90 patients (28.9 percent). The mean follow-up time was 90.7 (range, 11–160) months. Seventeen cancer-related deaths occurred during follow-up (18.9 percent), 6 of them in patients with micrometastases (23.1 percent) and 11 in patients without micrometastases (17.2 percent; P = 0.559). Cancer-specific five-year survival was 87 percent in the whole group and 81 percent in patients positive for micrometastases vs. 90 percent in negative patients (P = 0.489).CONCLUSIONS: The presence of micrometastases in patients with Stages I and II colorectal cancer seems not to have any impact on cancer-specific survival.Supported by the Apertus Research Program (Andromaco Pharmaceutical Company) and by The National Public Grant (FONDECYT #1000556).     

Prognostic Significance of Lateral Lymph Node Micrometastases in Lower Rectal Cancer

PURPOSE: The aims of this study were to determine the rate of lymph node micrometastases and to evaluate their prognostic value in lateral lymph nodes in lower rectal cancer at or below the peritoneal reflection. METHODS: A retrospective analysis was made of 892 lymph nodes from 66 consecutive patients who had undergone radical resection with lateral lymph node dissection. These lymph nodes were examined immunohistochemically with an antibody against cytokeratins 7 and 8, CAM5.2. RESULTS: Routine hematoxylin-eosin staining revealed 9 patients with positive lateral lymph nodes that were stained consistently with CAM5.2. Among 57 patients in whom lateral lymph node metastases were not detected by hematoxylin-eosin staining, cytokeratin staining was positive in 19 nodes (2.7 percent) from 11 patients (19.3 percent). These 11 patients with micrometastases in lateral nodes showed a significantly high recurrence rate (P = 0.048) and worse overall survival (P = 0.01) than the 46 patients without lateral node metastases. The recurrence rate and overall survival of patients with micrometastases did not differ significantly from those of patients with positive lateral nodes with hematoxylin-eosin staining. Local recurrence developed in 6 of 66 patients, but neither the presence nor the absence of micrometastases in lateral nodes influenced the local recurrence rate. CONCLUSION: The presence of nodal micrometastases leads to a poor prognosis. The survival of patients with micrometastases was not different from that of patients with overt metastases. Therefore, patients with cytokeratin-positive cells in lateral lymph nodes should be regarded as having overt metastases.     

Tumor micrometastases in mesorectal lymph nodes and their clinical significance in patients with rectal caner

AIM: To investigate the number, size, and status of lymph nodes within the mesorectum and to explore the prognostic significance of lymph node micrometastases in patients with rectal cancer. METHODS: Thirty-one patients with rectal cancer undergone total mesorectal excision between October 2001 and October 2002 were included. Mesorectal nodes retrieved from the resected specimens were detected with a combination of haematoxylin and eosin (HE) staining and immunohistochemistry (IHC). The relations between lymph node metastases, micrometastases and postoperative recurrence were analyzed. RESULTS: A total of 548 lymph nodes were harvested, with 17.7+/-8.2 nodes per case. The average number of metastatic nodes in HE-positive patients and micrometastatic nodes in IHC-positive patients was 5.2+/-5.1 per case and 2.2+/-1.3 per case, respectively. The mean size of all nodes and metastatic nodes was 4.1+/-1.8 mm and 5.2+/-1.7 mm in diameter, respectively. The mean size of micrometastatic nodes was 3.9+/-1.4 mm in diameter. The size of the majority of mesorectal nodes (66.8%), metastatic nodes (52.6%), and micrometastatic nodes (79.5%) was less than 5 mm in diameter. During a median follow-up period of 24.6+/-4.7 mo, 5 patients (16.7%) had recurrence, of them 2 died and 3 survived. Another case died of tumor unrelated cause and was excluded. All 5 recurrent cases had 3 or more nodes involved, and one of them developed only lymph node micrometastases. The mean number of both metastatic and micrometastatic nodes per case differed significantly between the recurrent and non-recurrent groups (P<0.01 and P = 0.01, respectively). CONCLUSION: The majority of lymph nodes, metastatic, and micrometastatic lymph nodes within the mesorectum are smaller than 5 mm in diameter. The nodal status and the number of lymph nodes involved with tumor metastases and micrometastases are related to the rapid postoperative recurrence.     

Micrometastases in the cervical lymph nodes in esophageal squamous cell carcinoma

Few studies have investigated the presence of lymph node micrometastases (MM) in the cervical region of patients with esophageal squamous cell cancer. The present study examines the presence of cervical MM and attempts to determine a way to predict the occurrence and site of such micrometastases. A total of 2203 cervical lymph nodes and 118 mediastinal recurrent nerve nodes obtained from 86 patients with esophageal carcinoma were examined immunohistochemically using cytokeratins. Cervical lymph nodes and mediastinal recurrent nerve nodes metastases were detected histologically in 33 and 41 of the 86 patients respectively. Cervical lymph node and mediastinal recurrent nerve node MM were immunohistochemically detected in 16 (18.6%) and 6 (7.0%) patients respectively. Of these 16 patients with cervical MM, seven were found to have lymph node metastases in different cervical regions, whereas cervical MM only were detected in nine patients. Among the former group of patients, five were diagnosed by ultrasound examination as having cervical lymph node metastases. Mediastinal recurrent nerve node metastases and MM correlated with the presence of cervical MM in all but one patient. Cervical lymph node metastasis, including micrometastasis, can be predicted by preoperative ultrasonography and the routine histologic examination of mediastinal recurrent nerve nodes.     

Mortality association of enhanced CD44v6 expression is not mediated through occult lymphatic spread in stage II colorectal cancer

BACKGROUND AND AIMS: In the absence of other metastatic disease, the presence of lymph node metastasis remains the most important determinant of survival in colorectal cancer (CRC). Cluster designation 44 variant 6 (CD44v6) over-expression is associated with worse outcome in all stages of CRC. The CD44v6 is believed to confer metastatic potential through its facilitation of migration, extravasation and proliferation, although the specific means by which it conveys an adverse prognosis in CRC is unknown. The aim of the present study was to determine if CD44v6 over-expression in Stage II CRC subjects was associated with the presence of lymph node micrometastases. METHODS: We assessed tumour CD44v6 expression in 43 randomly sampled subjects who had resections for Stage II CRC between 1984 and 1991 by using immunohistochemistry. Micrometastases were sought in corresponding lymph node (LN) sections using keratin immunohistochemistry. RESULTS: There was a statistical trend between tumour CD44v6 over-expression and mortality (P = 0.09) and a significant relationship between LN cytokeratins and mortality (P = 0.01). There was no association between the detection of LN cytokeratins and tumour CD44v6 over-expression. CONCLUSION: We conclude that the adverse survival effect of CD44v6 over-expression is not mediated though lymphatic spread and postulate that it may therefore facilitate haematogenous metastasis.     

Detection of micrometastases and skip metastases with ex vivo sentinel node mapping in carcinoma of the colon and rectum

Background The debate over sentinel lymph node mapping (SLNM) and focused pathologic examination to detect micrometastases in patients with colorectal cancer (CRC) continues. We present in this paper our experience with SLNM for CRCs to improve staging. In addition, we have detailed the mapping procedure on an anatomical basis to define skip metastasis. Materials and methods Forty-seven patients underwent ex vivo SLNM. Immediately after resection, 1 ml of patent blue VF was injected submucosally around the tumor. Lymph nodes harvested from the first 15 patients were mapped in a standard fashion as the blue-stained nodes (SLNs), and the others (non-SLNs) were dissected away. In the remaining 32 patients, the lymph nodes were also mapped separately in relation to their anatomic location and described as epicolic-paracolic, intermediate, and principal. The blue-stained nodes (SLNs) and non-SLNs, negative by hematoxylin and eosin stain, were further stained with cytokeratin immunohistochemical analysis and carcinoembryonic antigen. Results A total of 873 histologically confirmed LNs were examined with a mean of 18.6±8.1 nodes per patient. In 46 of 47 patients (97.8%), SLNs were identified. Immunohistochemical staining revealed micrometastases in the lymph nodes of four patients, which were negative by conventional methods. Anatomical skip metastases were noted in 4 of 32 patients studied (12.5%). Conclusion Ex vivo SLNM in CRCs is a feasible technique with a high SLN identification rate. Results of anatomical mapping of lymph nodes correlates with the limited literature, suggesting that occult skip metastases can occur in the apical lymph node group and may occur outside the resected area.     

The differentially mutational spectra of the APC, K-ras, and p53 genes in sporadic colorectal cancers from Taiwanese patients

BACKGROUND/AIMS: Adenomatous polyposis coli (APC), K-ras and p53 gene mutations are the most common genetic alterations present in colorectal cancer (CRC). The aim of this study was to analyze tumor mutation frequencies and spectra in a large cohort of Taiwanese patients with CRC. METHODOLOGY: APC, K-ras, and p53 gene mutations in primary tumor tissues and their paired normal tissues of 123 CRC patients were detected by polymerase chain reaction-single strand conformation polymorphism analysis, followed by direct sequencing. RESULTS: Of these 123 CRC patients, 43.1%, 44.7%, 35% of tumor tissue specimens presented mutations in APC, K-ras, and p53 genes, respectively. Overall, gene mutations in APC, K-ras and/or p53 were present in 78% (96/123) of tumor tissues. Among 96 CRC patients harboring gene mutations, 49 (51%) contained mutations of at least two different genes and 47 (49%) contained mutations of one gene only. The most common combination of gene mutations was APC and K-ras mutations (21.9%), followed by K-ras and p53 mutations (12.5%) and then APC and p53 mutations (10.4%). In addition, there were only 6.3% (6/96) of tumor tissues from CRC patients simultaneously containing mutations of APC, K-ras and p53 genes. The most common mutation spectrum of these genes was missense mutations, at a frequency of 38.8%, 92.7% and 70.5% for APC, K-ras and p53 genes, respectively. CONCLUSIONS: These data support that the frequencies and patterns of somatic mutation of the APC, Kras and p53 genes in CRCs are considerably variable and distinct among populations, for which the interaction between exogenous environmental factors and endogenous gene alterations may be important determinants.     

Sentinel lymph nodes of colorectal carcinoma: reappraisal of 123 cases

AIMS: Results concerning the usefulness of the sentinel lymph node (SLN) in colorectal carcinoma have been discordant. The SLN technique may be used to guide surgical resection (lymph mapping), restrict the lymph node analysis solely to the SLN (accuracy) and upgrade tumor staging when micrometastases are specifically detected in the SLN. METHODS: The blue dye injection technique was used. Serial sections of the SLNs were analyzed after hematoxylin-eosin (HES) staining. RESULTS: The SLN technique was tested in 123 patients, successfully in 112/118 (feasibility 95%) (five intraoperative exclusions). On average, twenty lymph nodes (range: 5-74) and two SLNs (range: 1-5) were identified. Lymph mapping was used in 11% of patients to guide surgical resection; the SLN was negative in 14 of 36 N+ patients (39% false-negatives); HES staining enabled detection of micrometastases in 8 of 84 initially N0 patients (10% secondary upgrading to N+). CONCLUSION: Limiting node analysis to the SLN cannot replace a complete pathology examination of all resected lymph nodes. Careful examination of serial sections of the SLN can however affect therapeutic decision making since staging may be upgraded in up to 10% of initially N0 patients.     

APPL1表达与结直肠癌发生发展的关系及意义

目的:研究APPL1蛋白在人结直肠癌组织中的表达情况与临床病理参数的关系.方法:收集35例新鲜结直肠癌及27例正常直肠黏膜组织,采用免疫组织化学SP法和RT-PCR法检测APPL1在结直肠癌组织及正常直肠黏膜组织中的表达.采用半定量积分分级对该蛋白的表达强弱进行评分.结果:免疫组织化学和RT-PCR结果显示,APPL1蛋白在结直肠癌组织以及正常直肠黏膜组织中普遍表达,但该蛋白和相应的mRNA在癌组织中的表达高于对照组(P<0.05).在35例结直肠癌组织中,APPL1表达与分化程度、淋巴结转移、TNM分期相关(P<0.05),与性别、年龄、肿瘤大小、组织学类型无明显相关(P>0.05).结论:APPL1蛋白在结直肠癌组织中的表达上调,且该蛋白表达与患者肿瘤的分化程度、淋巴结转移情况以及TNM分期有关.APPL1有可能成为结直肠癌治疗的一个新靶点.