Colorectal carcinoma and the relationship of peritoneal cytology

The safety and effectiveness of prophylactic hyperthermic intraperitoneal chemotherapy in patients with pathological T3-4 locally advanced colon cancer

INTRODUCTION

The safety and effectiveness of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) in pathological T3-4 locally advanced (pT3N + M0 and pT4NxM0) colon cancer (CC) patients with radical resection need further study.

METHODS

Clinical and pathological information of pT3-4 locally advanced CC patients who received radical surgery in our hospital from January 2018 to December 2020 were analyzed. The prognosis of patients was estimated using Cox proportional hazards regression analysis and Kaplan-Meier method.

RESULTS

Among 927 patients, 10.4% (96/927) received prophylactic HIPEC based on 5-FU, 4.6% (43/927) received prophylactic HIPEC based on lobaplatin, 85.0% (788/927) received conventional therapy. The incidence of metachronous peritoneal carcinomatosis (mPC) was 9.4%. Complications occurred in 32 patients (4.1%) in the conventional therapy group, 6 patients (6.3%) in the prophylactic HIPEC group based on 5-FU and 3 patients (7.0%) in the prophylactic HIPEC group based on lobaplatin within 30 days after surgery (5-FU vs. conventional therapy group, p = 0.464; Lobaplatin vs. conventional therapy group, p = 0.591). Multivariate Cox regression analysis revealed that prophylactic HIPEC based on either 5-FU or lobaplatin regimen could not effectively improve mPC-free survival (5-FU: p = 0.020, HR = 1.927, 95% CI, 1.111-3.343; Lobaplatin: p = 0.167, HR = 0.247, 95% CI, 0.034-1.796), overall survival (5-FU: p = 0.361, HR = 1.360, 95% CI, 0.703-2.634; Lobaplatin: p = 0.780, HR = 0.816, 95% CI, 0.195-3.416) and disease-free survival (5-FU: p = 0.525, HR = 1.149, 95% CI, 0.749-1.760; Lobaplatin: p = 0.117, HR = 0.488, 95% CI, 0.199-1.198).

CONCLUSION

Early prophylactic HIPEC based on 5-FU or lobaplatin subsequent to radical resection for patients with pT3-4 locally advanced CC is safe, but not effective in reducing the risk for mPC.

Risk factors for metachronous peritoneal carcinomatosis after radical resection for patients with nonmetastatic pT3-4 colon cancer

BACKGROUND

Patients with nonmetastatic pT3-4 colon cancers are prone to develop metachronous peritoneal carcinomatosis (mPC). Risk factors for mPC and the influence of mutant kirsten rat sarcoma viral oncogene (KRAS)/neuroblastoma rat sarcoma (NRAS)/v-raf murine sarcoma viral oncogene homolog B1 (BRAF) and DNA mismatch repair (MMR) status on mPC remain to be described in these patients.

METHOD

All enrolled patients were identified from the prospectively collected colorectal cancer database of a tertiary referral hospital between 2013 and 2018. Multivariate analysis was used to identify risk factors associated with mPC.

RESULTS

Of the 1689 patients with nonmetastatic pT3-4 colon carcinoma, 8.4% (142/1689) progressed to mPC. Endoscopic obstruction (HR = 3.044, p < 0.001), elevated CA125 (HR = 1.795, p = 0.009), pT (T4a vs. T3, HR = 2.745, p < 0.001; T4b vs. T3, HR = 3.167, p = 0.001), pN (N1 vs. N0, HR = 2.592, p < 0.001; N2 vs. N0, HR = 4.049, p < 0.001), less than 12 lymph nodes harvested (HR = 2.588, p < 0.001), mucinous or signet ring cell carcinoma (HR = 1.648, p = 0.038), perineural invasion (HR = 1.984, p < 0.001), and adjuvant chemotherapy (HR = 1.522, p = 0.039) were strongly related to mPC but that mutant KRAS/NRAS/BRAF and MMR status was not associated with mPC.

CONCLUSION

This study identified the high-risk factors for mPC in patients with nonmetastatic pT3-4 colon carcinoma, and these factors should be considered in selective preventive therapy and close follow-up for patients subsequently deemed to have high risk for mPC.

Use of ascitic CEA levels as a predictive value for distant metastasis in high-risk stage II and III colorectal cancer

PURPOSE

This study aimed to analyze the effect of ascitic carcinoembryonic antigen (CEA) levels on the long-term oncologic outcomes of colorectal cancer (CRC) following curative treatment.

METHODS

A total of 191 patients with stage II/III CRC were included. CEA was analyzed on the peritoneal fluid samples taken at the start of each surgery. Long-term oncologic outcomes were analyzed using known risk factors for recurrence in CRC.

RESULT

Multivariate analysis of recurrence showed that lymphatic invasion (hazards ratio (HR) 2.7, 95% confidence interval (CI) 1.1-7, p = 0.038), vascular invasion (HR 2.8, 95% CI 1.2-6.3, p = 0.013), mucinous cancer (HR 3.6, 95% CI 1.3-10.1, p = 0.017), and peritoneal fluid CEA exceeding 5 ng/dl (odds ratio 3.1, 95% CI 1.2-7.7, p = 0.017) were significant risk factors. There were 14 patients with liver metastasis, 11 of whom had high ascitic CEA levels and no peritoneal metastasis. Additionally, eight had lung metastasis, and seven of them had high ascitic CEA levels.

CONCLUSION

High ascitic CEA levels showed significantly lower disease-free survival and were significantly associated with distant metastasis in the lung and liver.

Flow cytometry-based analysis of tumor-leukocyte ratios in peritoneal fluid from patients with advanced gastric cancer

Background

The frequency of tumor cell dissemination in the peritoneal cavity is critically related to the progression of peritoneal metastases (PM). Recently, flow cytometry (FCM) has been successfully used to detect tumor cells in malignant effusions.

Methods

A total of 143 single cell suspensions derived from ascites or peritoneal lavages from patients with advanced gastric cancer (GC) were stained with monoclonal antibodies to CD45 and to CD326 as well as 4,6‐diamidino‐2‐phenylindole (DAPI) and FVS780. Using FCM, tumor‐leukocyte ratio (TLR) were calculated from CD45(−)CD326(+) tumor cell counts/ CD45(+)CD326(+) leukocyte counts in DAPI (+) FVS780(−) gated area. In 54 patients, the ratios of CD11b(+), CD4(+) and CD8(+) cells in CD45(+) leukocytes were evaluated in parallel.

Results

TLR of 69 patients with PM were significantly higher than those of 74 without PM (p < .001) and log(TLR) showed strong correlation with peritoneal cancer index scores in 51 PM (+) patients (r = 0.439). TLR in PM (+) patients also correlated with the ratio of CD11b (+) myeloid cells (r = 0.547), and correlated inversely with those of CD4(+) (r = −0.490) and CD8(+) T cells (r = −0.648). In PM (−) patients who underwent gastrectomy, TLR never exceeded 0.1% in patients with primary GC without serosal involvement (<T4). However, TLR in patients with T4 GC were significantly higher (p < .05) and peritoneal recurrence occurred in 6/8 patients whose TLR exceeded 0.1%.

Conclusion

TLR in peritoneal fluid reflects tumor burden and the immune environment in peritoneal cavity. Multicolor FCM may provide additional information which can be used for the treatment of the patients with PM.

Clinical significance of carcinoembryonic antigen in peritoneal fluid detected during operation in stage I-III colorectal cancer patients

BACKGROUND/AIMS

Early diagnosis of peritoneal metastases in patients with colorectal cancer (CRC) can influence patient prognosis. The aim of this study was to identify the clinical significance of carcinoembryonic antigen (CEA) in peritoneal fluid detected during operation in stage I-III CRC patients.

METHODS

Between April 2009 and April 2015, we reviewed medical records from a total of 60 stage I-III CRC patients who had peritoneal fluid collected during operation. Patients who had positive cytology in the assessment of peritoneal fluid were excluded. We evaluated the values of CEA in peritoneal fluid (pCEA) to predict the long-term outcomes of these patients using Kaplan-Meier curves and Cox regression models.

RESULTS

The median follow-up duration was 37 months (interquartile range, 21-50 months). On receiver operating characteristic analysis, pCEA had the largest area under the curve (0.793; 95% confidence interval, 0.635-0.950; P=0.001) with an optimal cutoff value of 26.84 (sensitivity, 80.0%; specificity, 76.6%) for predicting recurrence. The recurrence rate was 8.1% in patients with low pCEA (<26.84 ng/mL, n=37), and 52.2% in patients with high pCEA (≥26.84 ng/mL, n=23). In multivariate Cox regression analysis, high pCEA (≥26.84 ng/mL) was a risk factor for poor cancer-free survival (CFS) in stage I-III patients.

CONCLUSIONS

In this study, we determined that high pCEA (≥26.84 ng/mL) detected during operation was helpful for the prediction of poor CFS in patients with stage I-III CRC.

Applications of hyperthermic intraperitoneal chemotherapy for metastatic colorectal cancer

INTRODUCTION

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) plays a pivotal role in the current treatment of peritoneal carcinomatosis (PC) from colorectal cancer (CRC). Since the first demonstration, benefits for patients and especially an increase in survival have been described. In recent years, feasibility, efficacy and safety of HIPEC have been improved and progress has been made in understanding its oncological mechanism. Areas covered: In this article, leading publications have been reviewed including clinical trials to describe the clinical presentation of PC due to CRC and present recent evidence of the CRS/HIPEC procedure. The surgical approach including evaluation of the extent of PC is described and, in addition, the article reports about different HIPEC techniques as well as several protocols. Furthermore, the development and prognostic benefit of the combination of intraperitoneal and intravenous chemotherapy are outlined. Consideration has been given in particular to patient selection and the use of HIPEC if complete cytoreduction is not feasible. Expert commentary: The CRS/HIPEC procedure represents a curative approach to treat patients with PC from CRC. However, surgical skills and the HIPEC technique still require specialized oncological centers.

Flow Cytometric Quantification of Intraperitoneal Free Tumor Cells is a Useful Biomarker in Gastric Cancer Patients with Peritoneal Metastasis

BACKGROUND

The frequency of intraperitoneal free tumor cells (IPTC) is considered to reflect the severity of peritoneal metastasis (PM). We quantified the relative number of IPTC against leukocytes in peritoneal fluid and evaluated its clinical relevance in gastric cancer (GC) patients, particularly those with PM.

METHODS

Cells recovered from ascites or peritoneal lavage fluid were immunostained with monoclonal antibodies (mAb) to CD45 and CD326 (EpCAM). Using flow cytometry (FACS), CD326(+) and CD45(+) cells were classified as either tumor cells (T) or leukocytes (L) and the T/L ratio (TLR) was calculated in a total of 506 samples obtained from 300 patients with GC and 33 patients with liver cirrhosis (LC).

RESULTS

Median (M) of the TLR of the initial samples obtained from 199 patients with PM(+) GC was 1.32 % (0-1,868.44 %), which was significantly higher than that in patients with PM(-) GC (M = 0 %, 0-0.35 %; n = 101) or LC (M = 0 %, 0-0.031 %; n = 33). In 104 PM(+) patients who received combination chemotherapy including intraperitoneal paclitaxel, the TLR was repeatedly measured in peritoneal fluid obtained from the port. In these patients, the TLR showed a strong correlation with clinical features as well as cytological findings and carcinoembryonic antigen messenger RNA status. Finally, the median survival time of the 11 patients with initial TLR > 10 % was significantly shorter than that of the 52 patients with TLR < 10 % (271 vs. 627 days; p = 0.0002).

CONCLUSION

The TLR excellently reflected tumor burden in the peritoneal cavity, and could be a reliable biomarker to determine the outcome, as well as the effectiveness, of chemotherapy in patients with PM(+) GC.

Flow cytometric quantification of intraperitoneal free tumor cells in patients with peritoneal metastasis

BACKGROUND

Peritoneal metastasis (PM) is the most life-threatening type of metastasis in abdominal malignancy. To improve the diagnostic accuracy of cytologic detection (CY) of free tumor cells (FTC) in the peritoneal cavity, we tried to quantify the FTC to leukocyte ratio using flow cytometry in patients with peritoneal metastasis.

METHODS

Cells were recovered from ascites or peritoneal lavages from 106 patients who underwent abdominal surgery and additional 89 samples which were obtained from peritoneal catheter or access port in patients with PM (+) gastric cancer. The cells were immunostained with monoclonal antibodies to CD45 and to CD326 (EpCAM). Using flow cytometry, CD326 (+) and CD45 (+) cells were classified as either tumor cells (T) or leukocytes (L) and the T/L ratio (TLR) was calculated.

RESULTS

In 106 samples obtained by laparotomy, Median (M) of the TLR of PM (+) patients was 1.39% (0-807.87%) which was significantly higher than PM (-) patients (M=0%, 0-2.14%, P < 0.001). In PM (+) patients, 86 CY (+) samples showed higher TLR than 61 CY (-) samples (M=2.81%, 0.02-1868.44% vs. M=0%, 0-3.45%, p<0.0001). In all of the 24 patients who were monitored for TLR before and after intraperitoneal (IP) chemotherapy, the TLR was reduced which was more dramatic than the results of the change in cytology.

CONCLUSIONS

TLR measured with FACS is an excellent reflection of the tumor spread in the peritoneal cavity and could be a reliable diagnostic biomarker to determine the severity of PM as well as effectiveness of IP chemotherapy.

Impact of positive intraabdominal lavage cytology on the long-term prognosis of colorectal cancer patients

BACKGROUND

Our aim was to investigate the presence of free cancer cells found in lavage cytology specimens taken from the proximity of tumors during the course of curative open and laparoscopic colorectal resections and then examine and compare the long-term disease outcomes in cases of negative and positive cytology. Based on the results, we were hoping to identify the place of peritumoral lavage cytology among prognostic factors for disease recurrence.

METHODS

Between January 1, 2005 and December 31, 2007 intraoperative peritoneal lavage cytology was performed in 145 patients who underwent curative colorectal procedures. In all, 37 of the procedures were laparoscopic resections.

RESULTS

Malignant cells were detected in the intraoperative peritoneal lavage cytology samples from 25 patients. Median follow-up was 47 months (3-81 months). Among the 25 patients with positive cytology; locoregional recurrence or distant metastasis was found in 14 during this period (56 %), whereas among the 120 patients with negative cytology the incidence was 28 (23 %).

CONCLUSIONS

The impact of tumor stage, lymph node status, and peritoneal lavage cytology on recurrence rates is significant. Tumor, nodal, and lavage cytology status can be organized hierarchically in relation to time of recurrence. Cytology is most important, with positivity rendering long-term prognosis unfavorable. When comparing surgical techniques (open versus laparoscopic), we found no significant difference in recurrence rates. Our study has shown that conventional peritoneal lavage cytology is a prognostic factor in the case of patients undergoing curative colorectal operations.

Systematic review and meta-analysis of intraoperative peritoneal lavage for colorectal cancer staging

BACKGROUND

Intraperitoneal cancer cells are detectable at the time of colorectal cancer resection in some patients. The significance of this, particularly in patients with no other adverse prognostic features, is poorly defined. Consequently peritoneal lavage is not part of routine practice during colorectal cancer resection, in contrast with other abdominal malignancies. The aim of this systematic review was to determine the effect of positive intraoperative peritoneal cytology on cancer-specific outcomes in colorectal cancer.

METHODS

A systematic review of key electronic journal databases was undertaken using the search terms 'peritoneal cytology' and 'colorectal' from 1980 to 2012. Studies including patients with frank peritoneal metastasis were excluded. Meta-analysis for overall survival, local/peritoneal recurrence and overall recurrence was performed.

RESULTS

Twelve cohort studies (2580 patients) met the inclusion criteria. The weighted mean yield was 11·6 (range 2·2-41) per cent. Yield rates were dependent on timing of sampling (before resection, 11·8 per cent; after resection, 13·2 per cent) and detection methods used (cytopathology, 8·4 per cent; immunocytochemistry, 28·3 per cent; polymerase chain reaction, 14·5 per cent). Meta-analysis showed that positive peritoneal lavage predicted worse overall survival (odds ratio (OR) 4·26, 95 per cent confidence interval 2·86 to 6·36; P < 0·001), local/peritoneal recurrence (OR 6·57, 2·30 to 18·79; P < 0·001) and overall recurrence (OR 4·02, 2·24 to 7·22; P < 0·001).

CONCLUSION

Evidence of intraoperative peritoneal tumour cells at colorectal cancer resection is predictive of adverse cancer outcomes.

Intraperitoneal free cancer cells in non-gynaecological adenocarcinomas: a reproducibility study

OBJECTIVE

In recent years, therapeutic approaches including cytoreductive surgery followed by intraperitoneal chemotherapy have proven effective in peritoneal carcinomatosis of colorectal origin. If cytology is to be used to include patients in aggressive treatment regimens, it is necessary to evaluate its performance, particularly in terms of specificity. The aim of this study was to assess interobserver agreement for the detection of intraperitoneal free cancer cells (IFCCs) in patients with non-gynaecological adenocarcinomas.

METHODS

Over a 5-year period, 1223 patients were recruited in 19 French surgery departments. Peritoneal samples were examined in 14 dispersed pathology laboratories. Giemsa-stained slides were sent to a control reader blind to the previous diagnosis. Discordant cases, concordant positive results and a random selection of negative concordant cases were reviewed by a panel of seven cytopathologists. The 'final diagnosis' was that of the consensus meetings but took into account locally-processed slides.

RESULTS

Gathering dubious cases with negative results, a 95.6% concordance was achieved between local readers and the control reader. IFCCs were ascertained by the panel in 85 cases (7.0%). Eight of 873 colorectal cancers cases viewed locally were falsely positive (0.9%). Radiotherapy and neoadjuvant therapy had no impact on the false-positive rate as assessed by final validation by the panel (P > 0.05). Samples initially considered as dubious were reclassified as negative by the panel in 24 of 25 cases (96.0%).

CONCLUSIONS

The panel consensus allowed reclassification of most dubious/equivocal peritoneal cytology cases, whereas clearcut distinction between benign and malignant cases was correctly achieved in almost all cases.

Prognostic value of peritoneal cytology and the combination of peritoneal cytology and peritoneal dissemination in colorectal cancer

PURPOSE

The value of positive peritoneal cytology in colorectal cancer has been controversial. In this study, we aimed to clarify the prognostic significance of peritoneal cytology and the impact of the combination of peritoneal dissemination and peritoneal cytology on the prognostic evaluation of colorectal cancer.

METHODS

From January 1997 to December 2005, intraoperative peritoneal cytology was performed on 410 patients who had at least serosal invasion.

RESULTS

Thirty-one patients (7.6%) had positive peritoneal cytology. Patients with negative cytology showed a significantly better survival rate at five years than those with positive cytology (negative cytology, 68.0%; positive cytology, 20.6%; P < 0.0001). Multivariate analysis revealed that peritoneal cytology is one of the significant prognostic factors. Sixty percent of patients with positive cytology and 30.4% of patients with negative cytology recurred (P = 0.08). Regarding the recurrence site, patients with positive cytology showed a significantly higher recurrence rate of peritoneal dissemination than those with negative cytology (P = 0.0038). Some patients with positive cytology but without evident peritoneal dissemination achieved long-term survival. Additionally, some patients with macroscopic peritoneal dissemination and negative peritoneal cytology also achieved long-term survival. But for those patients with both positive cytology and evident macroscopic peritoneal dissemination, the five-year survival rate was zero.

CONCLUSIONS

Patients with negative peritoneal cytology had a significantly better five-year survival rate than those with positive peritoneal cytology. In some cases in which either peritoneal cytology or peritoneal dissemination was negative, long-term survival could be achieved.

Prognostic value of CEA and CA 19-9 tumor markers combined with cytology from peritoneal fluid in colorectal cancer

BACKGROUND

Early diagnosis and management of peritoneal metastases from colorectal cancer patients are difficult clinical challenges. The aims of this study were to evaluate the clinical significance of tumor markers and cytology in peritoneal effusions (PE) and peritoneal irrigation fluid (PI) and to determine their value as prognostic indicators in this disease.

METHODS

Two hundred thirty-four consecutive patients who underwent abdominal surgery for colorectal cancer from January 2006 to December 2007 were included, and tumor markers and cytology in PE and PI were analyzed prospectively.

RESULTS

The incidence of free cancer cells retrieved from peritoneal samples was 7.9%. Cytology was positive in 40.0% by Papanicolaou and Giemsa staining, 73.3% by hematoxylin and eosin staining of cell blocks, and 66.7% by carcinoembryonic antigen (CEA) and calretinin immunohistochemistry. Multivariate analysis revealed that peritoneal CEA and cancer antigen (CA) 19-9 in PI were correlated with peritoneal metastasis and cytology. Level of peritoneal fluid CEA was statistically significantly correlated with recurrence and peritoneal metastatic recurrence in patients with negative peritoneal cytology. Cytology, peritoneal CEA, and peritoneal CA 19-9 showed correlations with cancer-free survival and overall survival.

CONCLUSIONS

These correlations demonstrate the importance of continuous follow-up of peritoneal metastasis if there is positive cytology or an increase in CEA and CA 19-9 in peritoneal fluid.

Benefits of povidone-iodine solution in colorectal operations: science or legend

Povidone-iodine solution (Betadine) has long been accepted as an effective topical broad spectrum antiseptic, disinfectant, and tumoricidal agent. In colorectal operations, this solution generally has been used for the purpose of minimizing postoperative septic complications and reducing cancer recurrence, although the optimal application, advantages, and undesirable side effects have been debated. With limited prospective, randomized, controlled trials and insufficient data available, this article examines the safe and effective clinical applications of this solution for colorectal operations.

Peritoneal cytology in colorectal cancer: incidence and prognostic value

BACKGROUND

The value of peritoneal washing cytology on prognosis is not clear yet. The aims of our prospective study were to consider the incidence and prognostic value of peritoneal cytology.

METHODS

From 1996 to 2003, washing cytology was performed in 88 patients who underwent surgery for colorectal cancer. Before exploration and manipulation of the tumor, each of the peritoneal cavities next to the tumor site, subhepatic and rectovesical recesses, were irrigated with 50 mL saline, and then the aspirates were taken for cytological evaluation.

RESULTS

Thirteen (14.7%) of 88 patients had positive cytology. Although necrosis, depth of invasion, differentiation of the tumor, macroscopic peritoneal dissemination, and ascites were correlated with positive cytology; multivariate analyses revealed the depth of invasion, presence of necrosis, and differentiation of the tumor as the factors affecting the cytology. The disease-free and overall-survival times in patients with positive and negative peritoneal washing cytology were 56.36, 61.40 and 52.08, 63.94 months, respectively (P > .05).

CONCLUSION

The presence of free malignant cells in the peritoneal cavities of patients who underwent curative resection for colorectal cancer provides no further prognostic value over the current staging systems.

Prognostic significance of CEA levels and positive cytology in peritoneal washings in patients with colorectal cancer

OBJECTIVE

The aims of this prospective study were to determine carcinoembryonic antigen (CEA) levels and incidence of cytology in peritoneal washings of patients with colorectal cancer, correlate the results with various histopathological factors and determine their significance as prognostic factors of the disease.

METHODS

From 1992 to 1999, 98 patients with adenocarcinoma of the colon or intraperitoneal rectum underwent curative surgery and enrolled in this study.

RESULTS

Overall, 25 (26.3%) of 95 patients were found to have positive cytology. The proportion of patients with positive cytology was higher in the recurrence group (36.4%) than in the groups of 5-year survival and hepatic metastases (24.6% and 26.3%, respectively), but this difference was not significant. The 5-year survival group had the lowest peritoneal CEA levels compared with the other groups, but this difference was not significant. Peritoneal cytology and CEA level alone were not sensitive, specific or accurate enough indicators in predicting survival, hepatic metastases or local recurrence. The analysis of patients with positive cytology and high peritoneal CEA level revealed that their combination can predict local recurrence with accuracy of 85%.

CONCLUSIONS

The presence of free malignant cells, as detected by cytology and CEA level, in the peritoneal cavity of patients with resectable colorectal cancer had no detectable impact on survival, hepatic metastases or local recurrence rate. However, local recurrence can be predicted with accuracy of 85% in patients who have positive cytology and high peritoneal CEA level at the same time.

Peritoneal carcinomatosis of colorectal origin: incidence and current treatment strategies

OBJECTIVE

To review the literature with regard to the incidence and prognostic significance of peritoneal seeding during surgery for primary colorectal cancer (CRC), the incidence of intraperitoneal recurrence of CRC, and the current treatment strategies of established PC of colorectal origin, with special focus on cytoreductive surgery and intraperitoneal chemotherapy (IPEC).

SUMMARY BACKGROUND DATA

Although hematogenous dissemination forms the greatest threat to patients with CRC, peritoneal carcinomatosis (PC), presumably arising from intraperitoneal seeding of cancer cells, is a relatively frequent event in patients with recurrent CRC.

METHODS

The PubMed and Medline literature databases were searched for pertinent publications regarding the incidence and prognostic significance of exfoliated tumor cells in the peritoneal cavity during curative surgery for primary CRC, the incidence of intraperitoneal recurrence of CRC, and the therapeutic results of systemic chemotherapy or cytoreductive surgery followed by IPEC.

RESULTS

The incidence of peritoneal seeding during potentially curative surgery for primary CRC, as reported in 12 patient series, varied widely, from 3% to 28%, which may be explained by differences in methods to detect tumor cells. PC is encountered in approximately 7% of patients at primary surgery, in approximately 4% to 19% of patients during follow-up after curative surgery, in up to 44% of patients with recurrent CRC who require relaparotomy, and in 40% to 80% of patients who succumb to CRC. The reported median survival after systemic 5-fluorouracil-based chemotherapy for PC varies from 5.2 to 12.6 months. Median survival after aggressive cytoreductive surgery followed by (hyperthermic) IPEC in selected patients, as reported in 16 patient series, tends to be better and varies from 12 to 32 months at the cost of morbidity and mortality rates of 14% to 55% and 0% to 19%, respectively. One randomized controlled trial has been published confirming the superiority of aggressive surgical cytoreduction and intraperitoneal chemotherapy over strictly palliative treatment.

CONCLUSIONS

Peritoneal seeding of cancer cells possibly leading to PC is a rather common phenomenon in patients with CRC. Cytoreductive surgery and adjuvant (hyperthermic) IPEC have been shown to be efficacious in selected patients and should therefore be considered in patients with resectable PC of colorectal origin.

Laparoscopic Radical Nephrectomy: Long-Term Outcomes

BACKGROUND

Although more than a decade of experience with laparoscopic radical nephrectomy indicates it is an alternative to open surgery for localized renal-cell carcinoma (RCC), the long-term oncologic effectiveness of this procedure remains to be established.

MATERIALS AND METHODS

A thorough MEDLINE and PubMed literature research on long-term outcomes of laparoscopic radical nephrectomy was performed, and all pertinent articles were reviewed in detail. This review was formulated on the current cancer indication, the oncologic basis, the oncologic efficacy, and the longterm oncologic effectiveness of the procedure, including laparoscopic cytoreductive nephrectomy, with regard to metastasis, port-site tumor recurrence, and the relation to laparoscopic partial nephrectomy. Furthermore, the authors' previous report on the intermediate-term efficacy of laparoscopic radical nephrectomy was updated.

RESULTS

With increasing experience, the indications for laparoscopic radical nephrectomy continue to expand. There were many reports of intermediate-term, two reports of long-term, and our up-to-date outcomes analyzing the management of localized RCC that showed effective cancer control with no statistically significant difference between laparoscopic and open radical nephrectomy in the true 5- and 10-year survival analysis.

CONCLUSION

Long-term data, critical in the evaluation of any treatment for cancer, are currently available with respect to laparoscopic radical nephrectomy for localized RCC.

Free colorectal cancer cells on the peritoneal surface: correlation with pathologic variables and survival

BACKGROUND

Clinicopathologic staging of colorectal cancer remains the best predictor of survival. Prognostication for an individual with colorectal cancer remains elusive. This study was designed to investigate the incidence of free surface colorectal cancer cells detected by cytology during elective open curative resection, to correlate their presence with particular clinicopathologic variables and determine whether their presence was predictive of cancer-specific survival.

METHODS

Over a six-year period in one institution, all elective colon and intraperitoneal rectal cancer specimens were assessed during primary resection for the presence of free colorectal cancer cells by means of a simple and tested specimen imprint cytology methodology. Clinicopathologic variables were assessed prospectively and blinded to cytology results. All patients were followed up routinely until death and if the patient was not seen within the last six months, information was obtained from the New South Wales Registry of Births, Deaths and Marriages in Australia.

RESULTS

Overall, 26 of 281 (9.25 percent) colorectal cancers had positive cytology for cancer cells on the peritoneal surface of the bowel. Poorly differentiated tumors were significantly associated with positive cytology. Tumor penetration, presence of vascular or neural invasion, mucinous characteristics, lymph node status, and operative procedure performed were not statistically significant predictors of positive cytology. Overall, 43 of the 281 patients (15.3 percent) died during the mean follow-up period of 49.2 months from cancer-related deaths. Of these patients, 8 had positive cytology and 35 had negative cytology results. Cancer-specific survival assessed with the log-rank test was significantly associated with positive cytology in univariate (P = 0.008) and multivariate analysis (P < 0.001).

CONCLUSION

In this study, the presence of free surface colorectal cancer cells has been shown to be predictive of survival and is independent of direct peritoneal invasion and lymph node status. Thus, further assessment of this simple prognostic variable is warranted and selection of patients with positive cytology for possible adjuvant therapies may be beneficial.

Risk factors for peritoneal dissemination of colorectal cancer

BACKGROUND AND OBJECTIVES

The aim of this study was to clarify the risk factors associated with positive peritoneal dissemination (PPD) of colorectal cancer (CRC).

METHODS

From June 2000 to September 2002, 143 CRC patients who underwent elective curative (79.0%) or non-curative (21.0%) open laparotomy were prospectively studied. Clinical evaluations including classical factors, colonoscopic evaluation, intraoperative evaluation, and pathological features were recorded. PPD was diagnosed when macro- (MAPD) or microscopic peritoneal dissemination (MIPD) was evident. Positive peritoneal cytology from initially existing ascites or washing lavage indicated MIPD. Various factors were analyzed with univariate (Chi-square test) and then multivariate analyses (logistic regression test) to search for the risk factors of PPD.

RESULTS

Overall, MIPD, MAPD, and PPD were found in 2.8%, 6.3%, and 9.1%, respectively. Univariate analysis identified age (< or =59 years), CA19-9 (> or = 34.6 U/ml), poor differentiation, circumferential involvement (> or = 3 quadrants), ascites volume (>80 ml), pN+, and pT4 as risk factors of PPD. PPD did not occur in patients with well-differentiated tumors, less circumferential involvement (< 2 quadrants), or no lymph node metastasis. After multivariate analysis, CA19-9 (Odds ratio (95% CI), 8.6 (1.7-43.1)), pT4 (9.0 (1.3-61.0)), and age (5.26 (1.1-25.0)) remained significant risk factors.

CONCLUSION

CA19-9 (> or = 34.6 U/ml), pT4, and age (< or =59 years) were significant risk factors of PPD.

Experimental radioimmunotherapy of small peritoneal metastases of colorectal origin

Radioimmunotherapy using radiolabeled monoclonal antibodies (MoAbs) directed against tumor-associated antigens might be an effective treatment modality for small volume disease. Our aim was to optimize an experimental model of radioimmunotherapy for small peritoneal metastases of colorectal origin using the anti-CEA MoAb MN-14. In nude mice with intraperitoneal (i.p.) LS174T tumors, a protein dose-escalation study was carried out to determine the maximal dose of radioiodinated MN-14 to be used in radioimmunotherapy. The biodistribution of radioiodinated MN-14 was determined after intravenous (i.v.) and i.p. administration. Finally, the therapeutic efficacy of escalating activity doses of (131)I-labeled MN-14 (62.5-500 microCi) was assessed and compared to that of unlabeled MN-14 or 500 microCi of (131)I-labeled irrelevant control antibody. At protein doses higher than 25 microg, uptake in tumor was reduced, presumably due to saturation of tumor antigen. During the first 24 hours i.p. administration led to higher tumor uptake and higher tumor:blood ratios than i.v. administration. Median survival of the control groups was 38 days (unlabeled MN-14) and 52 days ((131)I-labeled nonspecific antibody). Median survival of the groups treated with increasing activity doses of (131)I-labeled MN-14 was 42 days (62.5 microCi), 49 days (125 microCi), 63 days (250 microCi) and 101 days (500 microCi), respectively (p < 0.0001 compared to unlabeled MN-14). The present study shows that the anti-CEA-antibody MN-14 preferentially accumulates in i.p. LS174T tumor xenografts after both i.p. and i.v. administration. Intraperitoneal radioimmunotherapy using (131)I-labeled MN-14 delays significantly the outgrowth of peritoneal LS174T metastases, even at relatively low activity doses.

Long-term prognostic value of conventional peritoneal cytology after curative resection for colorectal carcinoma

BACKGROUND

This study was undertaken to evaluate the long-term prognostic significance of conventional peritoneal cytology in patients with advanced colorectal carcinoma after curative resection.

METHODS

A review was performed of 189 patients who underwent curative resection for pT3/T4 carcinoma of the colon and upper/middle rectum between March 1987 and December 1991. Patient outcomes were reviewed retrospectively. Peritoneal cytology was performed before manipulation of the tumor. Intraoperatively, 50 ml of saline were instilled and 20 ml were reaspirated for cytology. In all patients, Papanicolaou and Giemsa stainings were performed to detect intraperitoneal free tumor cells.

RESULTS

The median follow-up was 103 months. Malignant cells were identified in peritoneal washings from 11 patients (5.8%). Of the 11 patients with positive cytology, six (54.5%) developed recurrence and peritoneal recurrence was observed in four (36.4%). In contrast, of the 178 patients with negative cytology, 46 (25.8%) developed recurrence and peritoneal recurrence was observed in four (2.2%). The peritoneal recurrence rate was significantly increased (P = 0.0004) in the patients with positive cytology. The cancer-specific 10-year survival rates for the patients with positive and negative cytology were 45.5 and 80.3%, respectively (P = 0.0051). Multivariate analysis (Cox proportional hazard model) revealed that peritoneal cytology (positive: P = 0.0256) and lymph node metastasis (pN2: P = 0.0004) were independent predictors of cancer-specific survival.

CONCLUSION

Conventional peritoneal cytology serves as a new prognostic marker after curative resection in patients with advanced colorectal carcinoma. It appears to be a useful diagnostic procedure for predicting recurrence, especially peritoneal recurrence.

The Incidence of Positive Peritoneal Cytology in Colon Cancer: A Prospective Randomized Blinded Trial

Many investigators have attempted to explain the suspected increased incidence of port site metastasis in patients undergoing laparoscopic colorectal resections for cancer with animal models in which cancer is simulated by injection of a tumor slurry into the peritoneal cavity. This approach makes the basic assumption that all patients with colorectal malignancies have viable cancer cells freely circulating within the peritoneal cavity. Recent reports in open colorectal resections have conflicting results. Some suggest that the true incidence is negligible and related to advanced-stage cancers whereas others implicate a much higher incidence. We initiated a prospective blinded trial to establish the true incidence of malignant peritoneal cytology in colorectal cancer. One hundred eight consecutive colon resections underwent conventional peritoneal cytologic evaluation. The patients included those with inflammatory conditions of the colon as well as malignant disease. The cytopathologist was blinded as to the indications for surgery as well as the final pathology result. In only one case—stage IV rectal cancer with peritoneal carcinomatosis—was the cytologic specimen positive. Malignant cytology appears to be an infrequent occurrence and is restricted to advanced-stage cancer.

Efficacy of surgical measures in preventing port-site recurrences in a porcine model

BACKGROUND

Port-site recurrences are serious complications of laparoscopy performed for cancer. Incidences reported in the literature vary between 0% and 21%, suggesting an influence of the surgeon.

METHODS

The aim of this experimental, prospective, randomized, single-blind study was to investigate the influence that the quality surgery has on the incidence of port-site recurrences. After a 12-mmHg carbon dioxide (CO2) pneumoperitoneum was created, 10(7) human HeLa cell were injected into the peritoneal cavity of 18 pigs, creating a xenogeneic tumor. Laparoscopic sigmoid resections then were performed using four trocars and a transanal double-stapling technique. The following protective measures were applied in nine animals: trocar fixation, prevention of gas leaks, rinsing of instruments with povidone-iodine, minilaparotomy protection, rinsing of trocars before removal, peritoneal closure, and rinsing of all wounds with povidoneiodine. Surgeons and type of procedures were randomized. After 4 weeks, the animals were killed and all portsites excised. Blinded immunohistologic analysis with antihuman pancytokeratin antibody was performed.

RESULTS

Tumor recurrence was present in 23 of 36 port sites (63.8%) in the control group, but only in 5 of 36 port sites (13.8%) in the group that received protective measures (p = 0.002; Fisher's exact test). No peritoneal carcinosis nor anastomotic recurrences were observed.

CONCLUSION

These results strongly suggest that the quality of surgical technique has an influence on the incidence of port-site recurrences. From now on, we propose to use these protective measures routinely in cancer laparoscopy.

Review of investigations regarding the etiology of port site tumor recurrence

The animal and human studies presented, at first glance, present a confusing and conflicting story. In regards to the animal studies, much of this confusion can be traced to the use of a variety of different models, none of which truly reproduces the human situation. Nonetheless, there is much to be gleaned from these efforts. The authors present conceptualization of the port wound tumor dilemma follows. In order for wound tumors to develop, viable tumor cells must be liberated from the primary tumor and find transport to a wound. Rarely, patients with colon tumors will present with or will develop widespread intraabdominal carcinomatosis. These tumors have the ability to spontaneously shed considerable numbers of viable cells which have the ability to implant on uninjured peritoneal surfaces. Unfortunately, the surgeon has little chance for success in these patients with either open or minimally invasive methods. Fortunately, most colon adenocarcinomas do not spread in this manner. Differences in the clinical behavior and manifestations of colon tumors most likely reflect the genetic makeup of individual tumors. Colonic neoplasm's ability to invade and metastasize varies considerably from tumor to tumor. Thankfully, as mentioned, the vast majority of colon tumors are not prone to cause carcinomatosis. Despite this fact, the human data available suggests that tumor cells can be found in the peritoneal cavity using sophisticated methods in about half of the patients after colectomy. If this is the case, then why aren't more wound tumors seen? Logic dictates that there must be a critical number of free intraabdominal cells above which successful wound seeding is likely. It makes sense that traumatization of the tumor will result in increased numbers of liberated cells. Therefore, surgical approach and technique should impact considerably on outcome. For the majority of colon tumors, if the lesion is assiduously avoided during mobilization and resection, it is unlikely that enough tumor cells will be shed to result in port site tumors. The recent interim results of the Cleveland Clinic's and the Barcelona randomized trials certainly support such a hypothesis. With over 300 patients enrolled (combined series) and with an average follow up of over 2 years, in neither trial has a port site tumor been noted. Similarly, with an average follow up of just under 3 years, Franklin et al noted that there were no port site tumors in their prospective trial of 191 consecutive laparoscopic colectomies for cancer. In the clinical setting, experience and surgical expertise seem to be the best predictor of outcome, in regards to wound tumors. The few animal studies that allow assessment of the impact of technique (i.e. those that utilize an intraabdominal solid tumor model which allows tumor excision) indeed support this hypothesis. In these studies poor technique resulted in significantly more wound tumors. Furthermore, it has been shown that for laparoscopic procedures, there is a definite learning period during which the incidence of wound tumors is considerably higher than that of open resection. With experience the laparoscopic incidence falls to that of open resection. Furthermore, a number of recent studies suggest that is possible to lower the incidence of wound tumors via peritoneal and wound irrigation with a variety of agents. These animal study results are in keeping with the recent clinical results. Both would suggest that given proper and adequate training and with sufficient attention being paid to avoid tumor handling that the incidence of wound tumors will be as low as that following open colectomy. How large a part, if any, does the CO2 pneumoperitoneum play in the port wound tumor story? Certainly, the results of the bulk of the animal studies performed, to date, have suggested that the CO2 pneumoperitoneum plays a critical role in the development of port wound tumors. With few exceptions, these studies have utilized tumor cel