R. Kube

Comparison of 17,641 Patients With Right- and Left-Sided Colon Cancer: Differences in Epidemiology, Perioperative Course, Histology, and Survival

PURPOSE: There is a growing amount of data suggesting that carcinomas of the right and left colon should be considered as different tumor entities. Using the data and analysis compiled in the German multicentered study “Colon/Rectum Cancer,” we aimed to clarify whether the existing differences influence clinical and histological parameters, the perioperative course, and the survival of patients with right- vs left-sided colon cancer. METHODS: During a 3-year period data on all patients with colon cancer were evaluated. Right- and left-sided cancers were compared regarding the following parameters: demographic factors, comorbidities, and histology. For patients who underwent elective surgery with curative intent, the perioperative course and survival were also analyzed. RESULTS: A total of 17,641 patients with colon carcinomas were included; 12,719 underwent curative surgery. Patients with right-sided colon cancer were significantly older, and predominantly women with a higher rate of comorbidities. Mortality was significantly higher for this group. Final pathology revealed a higher percentage of poorly differentiated and locally advanced tumors. Rate of synchronous distant metastases was comparable. However, hepatic and pulmonary metastases were more frequently found in left-sided, peritoneal carcinomatosis in right-sided carcinomas. Survival was significantly worse in patients with right-sided carcinomas on an adjusted multivariate model (odds ratio, 1.12). CONCLUSIONS: We found that right- and left-sided colon cancers are significantly different regarding epidemiological, clinical, and histological parameters. Patients with right-sided colon cancers have a worse prognosis. These discrepancies may be caused by genetic differences that account for distinct carcinogenesis and biological behavior. The impact of these findings on screening and therapy remains to be defined.

Primary appendiceal carcinoma – Epidemiology, surgery and survival: Results of a German multi-center study

BACKGROUND While carcinoma of the colon is a common malignancy, primary carcinoma of the appendix is rare. Many retrospective reviews outlined experience from different centers on appendiceal neoplasms. However, the study population is often small because it is so rare. The aim of this study was to analyze the type of surgery and survival of patients with appendiceal malignancies using data from a German multi-center observational study (31 341 patients). METHODS During a five-year period, 196 consecutive patients with malignant appendiceal tumors were distributed into four groups: appendiceal carcinoids, adenocarcinoma, mucinous adenocarcinoma and adenosquamous carcinoma. The following parameters were analyzed: demographics, clinical presentation, comorbidities, type and appropriateness of surgery, final pathology and survival. RESULTS Adenocarcinoma had the highest incidence (50.5%). The most common presentation was that of acute appendicitis. Mean age at presentation was youngest for carcinoid tumors. Carcinoid tumors had lowest tumor size and localized disease was present in 72.9%. Metastatic spread at presentation was highest for adenosquamous and mucinous adenocarcinoma and each had a distinct pattern. Right hemicolectomy was performed in 71.4%, limited resection in 11.7%. Overall 5-year survival was 83.1% for carcinoid vs. 49.2% for non-carcinoid tumors. Histological subtype and tumor stage significantly affected survival. CONCLUSIONS Long-term outcome of carcinoid tumors is superior to non-carcinoid neoplasms. Among all appendiceal neoplasms, adenosquamous carcinoma is the rarest histological subtype which is most commonly associated with advanced tumor stage and worst prognosis. Appropriate oncologic resection is being performed in a significant percentage of cases in Germany. However, the high rate of right hemicolectomy in patients with small carcinoid tumors needs to be critically discussed.

Conversion from laparoscopic to open colonic cancer resection – Associated factors and their influence on long-term oncological outcome

PURPOSE Comparisons of open and laparoscopic colon cancer resection have shown that laparoscopy offers an oncologically safe option. However, there are no data on long-term influence of converted resection, despite conversion rates of up to 30% and the general observation that short-term outcome is significantly worsened. The aim was to compare the long-term results of primary open resection (OR), purely laparoscopic resection (LR-p) and converted resection (LR-c). METHODS In a prospective study at 282 German hospitals demographic, tumor- and treatment-related data and disease-free survival were compared in the three groups. RESULTS 8015 of 8307 patients with OR, 280 of 290 patients with LR-p and 55 of 56 patients with LR-c were followed for 39.5 months (median). Overall, no statistically significant differences were seen for five-year DFS (74.8%, 81.3% and 65.6%). However, for patients in stage II with conversion, the five-year DFS was significantly poorer (43.3%) than for OR (80.5%; p=0.003) and LR-p patients (92.5%; p=0.001). For stages I and III no differences were observed. CONCLUSION Conversion of laparoscopic colon cancer resection worsens DFS in locally advanced stage II carcinoma. There is a need to reduce the conversion rate by adequate patient selection for laparoscopic resection by experienced surgeons.

Incidence of synchronous liver metastases in patients with colorectal cancer in relationship to clinico-pathologic characteristics. Results of a German prospective multicentre observational study

BACKGROUND The aim of this prospective observational multicentre study was to evaluate the incidence of synchronous liver metastases in colon and rectal cancer and to determine clinico-pathologic factors of the colorectal cancer that influenced the development of synchronous liver metastases. METHODS Of 48,894 patients with colorectal cancer and who underwent surgery between January 2000 and December 2004, 7209 developed hepatic metastases and were analyzed. RESULTS Synchronous liver metastases occurred in 14.7% of the colorectal cancer cases. Colon cancer (15.4%) led significantly more frequently to haematogenous spread to the liver than rectal cancer (13.5%) in a univariate approach. The N, V, and T stage, as well as the number of metastatic-involved local lymph nodes independently influenced the frequency of synchronous liver metastases in colon and rectal cancer in a multivariate analysis. Localization of the cancer in the colon led to a different number of synchronous liver metastases. Localization of the rectal cancer did not influence the rate of synchronous liver metastases. In the case of synchronous liver metastases, patients with colon cancer had significantly more peritoneal metastases (17.9 vs. 9.15%) but less lung (9.7 vs. 14%) and bone (0.7 vs. 1.6%) metastases. Simultaneous curative liver resections were done in 7% of colon cancer cases and in 8.8% of rectal cancer cases. CONCLUSION In this national study the incidence of synchronous liver metastases in colon and rectal cancer were different. Independent factors leading to synchronous liver metastases could be identified. Venous infiltration seems to be important for the development of distant metastases.

The significance of Meckel's diverticulum in appendicitis--a retrospective analysis of 233 cases.

Conflicting reports are found in the literature concerning whether to remove an incidentally discovered Meckel’s diverticulum (MD). Between 1.1.1974 and 31.12.2000, at a single center, the perioperative data associated with appendectomy (AE) were recorded consecutively and analyzed retrospectively. All patients in whom an MD was discovered during an AE were included in the study. The clinical presentation, postoperative course, and follow-up in all MDs left in place were analyzed. During the course of 7927 AE, 233 MD (2.9%) were detected. Of these 80.7% (n = 188) were removed and 19.3% (n = 45) were left untouched. In 9% (n = 21) of all detected diverticula pathological changes were found. Ectopic tissue was seen in 12.2% (n = 23) of the MDs removed. The postoperative complication rates did not differ significantly between patients in whom the MD was removed (9.5%; n = l8) and those in whom it was not (17.7%; n = 8); in the latter group the appendicitis was of the more acute type (gangrenous or perforated) (24.4% vs. 4.3%). In 18 patients (40.0%) with non-removed MDs, a follow-up period of 14.1 ± 5.8 years was achieved. Complications associated with a non-removed MD were not observed. If during the course of an AE a MD is detected, the present data, as well as those in the literature, suggest that an individualized approach should be taken. Meckel’s diverticulum with obvious pathology should always be removed. In cases of gangrenous or perforated appendicitis, an incidentally discovered MD should be left in place, whereas in an only mildly inflamed appendix it should be removed.

Surgical practices for malignant left colonic obstruction in Germany

AIM Data from the multicentric observation study Kolon/Rektum-Karzinome (Primärtumor) (primary colorectal carcinoma) are adduced to assess the status of surgical treatment of this condition in Germany and to compare different operative approaches in the emergency treatment of obstructive left-sided colon cancer, especially diversion (Hartmanns procedure) and primary anastomosis. PATIENTS AND METHODS Out of 15,911 patients with cancer of the left colon, recorded between 01.01.2000 and 31.12.2004, a total of 743 patients underwent emergency surgery for an obstructive tumour, performed as a radical resection. These patients were compared in respect of their risk profile and postoperative result. RESULTS In 57.9% (n=430) a one-stage operation (Group I), in 11.7% (n=87) a primary anastomosis with protective stoma (Group II), and in 30.4% (n=226), Hartmanns procedure (Group III) was performed. In Group III more patients were male, overweight and multimorbid, and more had advanced-stage tumours. The morbidity and hospital mortality (overall hospital mortality, 7.7%; n=57) did not differ significantly between the groups. The insertion of a protective stoma did not affect the rate of anastomotic insufficiency (Group I, 7%; Group II, 8.0%). CONCLUSIONS Primary anastomosis for emergency left colon carcinoma obstruction should only be regarded as indicated in cases where the risk profile is favourable. Our results suggest that in advanced obstruction and in high-risk cases Hartmanns procedure should be used. A protective stoma did not appear to confer any advantage.

Influence of anatomical subsite on the incidence of microsatellite instability, and KRAS and BRAF mutation rates in patients with colon carcinoma

There is a growing amount of data supporting the concept that cancers originating from the proximal and distal colon are distinct clinicopathological entities. The incidence of MSI and BRAF mutation is strongly associated with right sided tumor location, whereas there are conflicting results for KRAS mutation rates. However, to date, no data exist whether and to what extent defined colonic subsites influence MSI status, KRAS and BRAF mutation rates. We selected primary colon cancer from 171 patients operated on at our institution between 2007 and 2010. BRAF, KRAS mutation rates and microsatellite instability were determined and correlated with clinicopathological features and tumor location. MSI-h cancers were significantly associated with poor histological grade but a lower rate of distant metastases. KRAS-mutated tumors were linked to lower T-stage and better differentiation. Colon carcinomas with BRAF mutation were significantly associated with distant metastatic spread and poor histological grade. Furthermore, we found that MSI-h status, KRAS and BRAF mutation rates varied remarkably among the colonic subsites irrespective of right- and left-sided origin, respectively. The results of the current study provide further evidence that a simple classification into right- and left-sided colon carcinoma does not represent the complexity of this tumor entity.

Quality assessment of colorectal cancer care: an international online model

Aim  We present an alternative approach to quality assessment in colorectal cancer, enabling a direct comparison of improvement at the level of the care provider.

Low‐volume centre vs high‐volume: the role of a quality assurance programme in colon cancer surgery

Aim  The study aimed to determine whether hospitals within a quality assurance programme have outcomes of colon cancer surgery related to volume.

Karzinome des rechten und linken Kolons – verschiedene Tumorentitäten?

PURPOSE Colorectal cancer is one of the most common malignancies in the Western world. In the past two decades, a growing amount of data has been reported suggesting that carcinomas of the right and left colon should be considered as different tumour entities. The aim of this review is to present a detailed analysis of the current knowledge regarding differences between right- and left-sided colon cancer and potential consequences for daily practice. METHODS For this report all articles with relevant information on differences between right- and left-sided colon carcinoma found via Pubmed searches were analysed. Furthermore, findings of a previous study performed by our group were included. RESULTS Patients with right-sided colon cancer are significantly older, predominantly women, with a higher rate of comorbidities. Most of the large epidemiological studies reported a continued rightward shift of colorectal cancer. Histopathologically, carcinoma of the right colon show a higher percentage of poorly differentiated, locally advanced tumours with a higher rate of mucinous carcinoma and different pattern of metastatic spread. Survival is significantly worse in patients with right-sided carcinomas. There are numerous genetic differences which account for the distinct carcinogenesis and biological behaviour. CONCLUSIONS The numerous findings regarding differences between right- and left-sided colon cancers should have an impact on colon cancer screening and therapy. Firstly, there are defined risk groups which should receive complete colonoscopy, particularly if they present with symptoms suspicious for colon carcinoma. Furthermore, location of the colon cancer should be considered before group stratification into genetic, clinical and especially chemotherapy trials. A more tailored approach to colon cancer treatment would be highly desirable if future trials further support the hypothesis of two distinct tumour entities.