Can intra-operative intraperitoneal free cancer cell detection techniques identify patients at higher recurrence risk following curative colorectal cancer resection: a meta-analysis

Long noncoding RNA small nucleolar RNA host gene 1 as a potential novel biomarker for intraperitoneal free cancer cells in colorectal cancer

Colorectal cancer (CRC) is a prevalent cancer with intraperitoneal free cancer cells (IFCCs) playing a significant role in prognosis, especially during surgeries. The identification of IFCCs is crucial for determining the stage and treatment of patients with CRC. Existing methods for IFCC detection, such as conventional cytology, immunocytochemistry (ICC), and polymerase chain reaction (PCR), have limitations in sensitivity and specificity. This study investigates the potential of long noncoding RNA (lncRNA) SNHG1 as a biomarker for detecting IFCCs in patients with CRC. Testing on a cohort of 91 patients with CRC and 26 patients with gastrointestinal benign disease showed that SNHG1 outperformed CEA in distinguishing CRC cells and detecting IFCCs across different disease stages. SNHG1 demonstrated higher sensitivity (76.1% vs. 43.1%) and specificity (68.4% vs. 52.3%) than CEA for IFCC detection in patients with CRC, suggesting its promising role as a clinical method for identifying IFCCs in CRC.

Phase 1 trial of same day cytology to guide the use of HIPEC

Background

Peritoneal metastases from gastrointestinal or gynecologic malignancy are a prominent part of the natural history of these diseases. Peritoneal metastases, if not effectively treated, will result in a decreased survival and cause an impaired quality of life. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment specifically designed to combat peritoneal metastases. A group of patients who, from a theoretical perspective, may benefit from HIPEC are those patients with a positive peritoneal cytology. In order to identify these patients at the time of a surgical intervention, a same day cytology is to be performed.

Materials and methods

The result of this test is to be available at or before the completion of the cancer resection. If the cytology is positive, the patient immediately becomes a candidate for HIPEC. The HIPEC will be of maximal value if a complete cytoreduction, as judged by the surgeon, has been possible. This phase 1 trial is to demonstrate that the Surgical Oncology Service, the Department of Pathology, the Pharmacy and the Operating Room personnel can co-ordinate a phase 1 protocol to successfully complete the same day cytology with an efficient delivery of HIPEC. A standardized plan for consent, cytology collection, preparation of the specimen, reading of the specimen, reporting the results in a timely manner facilitates the administration of HIPEC in peritoneal cytology positive patients.

Dissemination

Successful completion of these requirements is a positive result for this study and allows for future protocols to be generated. Successful completion of the same day cytology phase 1 protocol will allow the efficacy, safety, and efficiency of this plan of patient management to be evaluated.

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

PCR-based quantitative detection of intraperitoneal free cancer cells for predicting locoregional recurrence after rectal cancer resection

INTRODUCTION

Locoregional recurrence after curative resection remains an important issue in the treatment of colorectal cancer (CRC). The aim of the present study was to investigate the clinical significance of quantitative detection of intraperitoneal free cancer cells by a PCR-based method for predicting locoregional recurrence after CRC resection.

METHOD

A total of 114 patients with CRC were enrolled between March 2017 and December 2018, and 95 patients with Stage I-III CRC were analyzed. Peritoneal lavage fluid was collected before and after tumour resection and subjected to cytology and quantitative reverse transcription-PCR (qRT-PCR) with carcinoembryonic antigen (CEA) as a genetic marker.

RESULTS

2.1% of patients had positive cytology after resection, whereas 9.5% had positive CEA qRT-PCR (PCR+) after resection. Eight of nine PCR+ patients after resection had tumours in the rectum. Fifteen (15.8%) patients developed recurrence during the follow-up period, including three with locoregional recurrence. One of 86 (1.2%) PCR- patients and 2 of 9 (22.2%) PCR+ patients after resection developed locoregional recurrence. Overall and in rectal cancer patients, the 3-year cumulative risk of locoregional recurrence was 25.0% and 28.6% for PCR+ patients, which is significantly higher than PCR- patients (1.3% and 0%, P < 0.001 and P = 0.001, respectively).

CONCLUSION

Intraperitoneal free cancer cells can serve as a sensitive predictor of locoregional recurrence after rectal cancer resection. qRT-PCR for CEA can be a suitable method for detecting intraperitoneal free cancer cells in peritoneal lavage fluid.

Factors Affecting Positive Peritoneal Lavage Cytology in Patients with Stage II and III Colorectal Cancer with R0 Resection: A Multi-institutional, Prospective Study

Objectives:

This study aimed to explore the risk factors associated with cancer cell exfoliation in Stage II and III colorectal cancer (CRC).

Methods:

This multicenter, prospective, observational study targeted 1,698 patients with cStage II and III CRC who underwent R0 resection between 2013 and 2017. Clinicopathological variables were analyzed for correlations with positive peritoneal lavage cytology (PLC).

Results:

The positive PLC rate was 2.7% (46/1,694 cases) at laparotomy and 1.6% (25/1,590 cases) after tumor resection. Logistic regression analyses identified that undifferentiated histologies diagnosed by preoperative biopsy specimen, cT4, and pN+ were independent factors that affected the positive PLC at laparotomy. The positive PLC rate at laparotomy was 4.5% (33/736 cases) among the patients with undifferentiated histology and/or cT4. Logistic regression analyses revealed that the presence of ascites and undifferentiated histology by biopsy independently affected positive PLC after tumor resection.

Conclusions:

The undifferentiated histology and/or T4 indicated by preoperative diagnosis were identified as factors affecting PLC at laparotomy. Furthermore, ascites and preoperative histological type were identified as factors affecting positive PLC after tumor resection. As factors affecting positive PLC, these preoperative findings were found to be equivalent to pathological findings.

Peritoneal cytology as an indicator of peritoneal metastases in colorectal cancer

BACKGROUND

In the management of peritoneal metastases from colon and rectal cancer, the most favorable results are reported with an aggressive combined treatment on patients who have a small extent of the disease. A test to detect occult peritoneal metastases would greatly facilitate the management of this component of colorectal dissemination.

METHODS

Currently, the standard test by which to confirm the diagnosis of the peritoneal spread of colorectal cancer is peritoneal cytology. To study the utility of this test, we gathered information from patients with biopsy-proven peritoneal metastases. The clinical, histologic, and treatment-related features of these patients at the time of a cytoreductive surgery were statistically correlated with the results of the peritoneal cytology test.

RESULTS

Forty-nine patients with colorectal cancer peritoneal metastases and a peritoneal cytology determination at the time of a cytoreductive surgery were available for analysis. Twenty-eight patients (55.1%) had a positive test. Patients with a high peritoneal cancer index and mucinous histology were most likely to have positive peritoneal cytology.

CONCLUSION

Peritoneal cytology identified patients with mucinous histology and a large extent of disease but was consistently negative in patients who had a small extent of disease compatible with a favorable response to treatment.

Site of Recurrence and Survival After Surgery for Colorectal Peritoneal Metastasis

BACKGROUND

Multimodal treatment, including systemic treatment and surgery, improved the prognosis of peritoneal metastasis (PM). Despite all efforts, recurrence rates remain high, and little data are available about clinical behavior or molecular patterns of PM in comparison to hematogenous metastasis. Here, we aimed to analyze recurrence patterns after multimodal treatment for PM from colorectal cancer.

METHODS

Patients with colorectal PM undergoing multimodal treatment including systemic chemotherapy and cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) between 2005 and 2017 at 4 centers were analyzed retrospectively.

RESULTS

A total of 505 patients undergoing CRS/HIPEC were analyzed. Of the patients, 82.1% received preoperative chemotherapy. Median peritoneal cancer index was 6 (interquartile range = 3-11). Median disease-free and overall survival was 12 (95% confidence interval [CI] = 11 to 14) months and 51 (95% CI = 43 to 62) months, respectively. Disease recurred in 361 (71.5%) patients, presenting as isolated peritoneal recurrence in 24.6%, isolated hematogenous recurrence in 28.3%, and mixed recurrence in 13.9% of patients. Recurrence to the peritoneum was associated with an impaired time from recurrence to death of 21 (95% CI = 18 to 31) months for isolated peritoneal and 22 (95% CI = 16 to 30) months for mixed recurrence, compared with 43 (95% CI = 31 to >121) months for hematogenous recurrence (hazard ratio [HR] = 1.79, 95% CI = 1.27 to 2.53; P = .001; and HR = 2.44, 95% CI = 1.61 to 3.79; P < .001). On multiple logistic regression analysis, RAS mutational status (odds ratio [OR] = 2.42, 95% CI = 1.11 to 5.47; P = .03) and positive nodal stage of the primary (OR = 3.88, 95% CI = 1.40 to 11.86; P = .01) were identified as predictive factors for peritoneal recurrence.

CONCLUSIONS

This study highlights the heterogeneity of peritoneal metastasis in patients with colorectal cancer. Recurrent peritoneal metastasis after radical treatment represents a more aggressive subset of metastatic colorectal cancer.

Risk factors and risk prediction models for colorectal cancer metastasis and recurrence: an umbrella review of systematic reviews and meta-analyses of observational studies

BACKGROUND

There is a clear need for systematic appraisal of models/factors predicting colorectal cancer (CRC) metastasis and recurrence because clinical decisions about adjuvant treatment are taken on the basis of such variables.

METHODS

We conducted an umbrella review of all systematic reviews of observational studies (with/without meta-analysis) that evaluated risk factors of CRC metastasis and recurrence. We also generated an updated synthesis of risk prediction models for CRC metastasis and recurrence. We cross-assessed individual risk factors and risk prediction models.

RESULTS

Thirty-four risk factors for CRC metastasis and 17 for recurrence were investigated. Twelve of 34 and 4/17 risk factors with p < 0.05 were estimated to change the odds of the outcome at least 3-fold. Only one risk factor (vascular invasion for lymph node metastasis [LNM] in pT1 CRC) presented convincing evidence. We identified 24 CRC risk prediction models. Across 12 metastasis models, six out of 27 unique predictors were assessed in the umbrella review and four of them changed the odds of the outcome at least 3-fold. Across 12 recurrence models, five out of 25 unique predictors were assessed in the umbrella review and only one changed the odds of the outcome at least 3-fold.

CONCLUSIONS

This study provides an in-depth evaluation and cross-assessment of 51 risk factors and 24 prediction models. Our findings suggest that a minority of influential risk factors are employed in prediction models, which indicates the need for a more rigorous and systematic model construction process following evidence-based methods.

Patient selection for cytoreductive surgery and HIPEC for the treatment of peritoneal metastases from colorectal cancer

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a viable option for selected patients with peritoneal metastases (PM) from colorectal origin, resulting in long-term survival and even cure in some cases. However, adequate patient selection for this treatment is currently one of the major challenges. The aim of this review is to provide a comprehensive overview of clinically relevant factors associated with overall survival. This may help to guide clinicians through the complex interplay of patient, tumor, and treatment characteristics to adequately select patients who benefit the most from this extensive surgical treatment. First, basic principles of colorectal PM and the CRS and HIPEC treatment will be discussed. According to available literature, especially extent of peritoneal disease, completeness of cytoreduction, and signet ring cell histology have great influence on the outcome after CRS and HIPEC. Other factors that seem to have a negative prognostic value are the presence of liver metastases and the absence of treatment with neo-adjuvant systemic therapy. Prognostic models combining the above-mentioned factors, such as the Colorectal Peritoneal Metastases Prognostic Surgical Score nomogram, may provide clinically relevant tools to use in everyday practice.

Strategies to prevent peritoneal carcinomatosis arising from colorectal cancer

In the last decades, cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy became a curative option for peritoneal metastases in selected patients, otherwise considered for palliative therapy alone. Better knowledge of physiopathology of peritoneal spread and identification of predictive factors for peritoneal relapse prompted specialized centers to investigate the role of a 'proactive approach' in order to early detect peritoneal metastasis. These encouraging data could justify an active attitude in selected patients at high risk of peritoneal recurrence after curative resection of primary tumor. Selection criteria and the timing of complementary hyperthermic intraperitoneal chemotherapy remain important points of discussion. In this article, we will discuss treatment principles and future perspectives to early treat and, if possible, to prevent peritoneal dissemination after curative treatment of colorectal cancer.

Intraperitoneal-Free Cancer Cells Represent a Major Prognostic Factor in Colorectal Peritoneal Carcinomatosis

BACKGROUND

Intraperitoneal-free cancer cells are considered as an important prognostic tool in gastric and ovarian cancer. However, their significance in colorectal cancer remains more controversial.

OBJECTIVE

This study aimed to determine the role of intraperitoneal-free cancer cells as a prognostic tool in the outcome in colorectal peritoneal carcinomatosis treated with curative intent by complete cytoreductive surgery.

DESIGN

This study is an analysis of a prospectively maintained database.

PATIENTS

Between 1991 and 2012, all patients treated in a single institution for colorectal peritoneal carcinomatosis by complete cytoreductive surgery with peritoneal cytology available were evaluated. Peritoneal cytology was stained in the conventional way (May Grumwald Giemsa).

RESULTS

Among a population of 162 patients treated for colorectal peritoneal carcinomatosis by complete cytoreductive surgery, 38 presented positive intraperitoneal-free cancer cells (23.5%). Systemic chemotherapy was administered to 135 patients (85%) during the preoperative course. Median follow-up was 34.5 months. Median overall survival was 19 and 44 months for positive and negative intraperitoneal-free cancer cells (p = 0.018). In multivariate analysis, Peritoneal Carcinomatosis Index and positive intraperitoneal-free cancer cells were significant prognostic factors of overall survival (HR, 2.3 (1.18-4.52), p = 0.014; HR, 1.9 (1.08-3.38), p = 0.027).

LIMITATIONS

Retrospective analysis and the long period were limitations of study.

CONCLUSION

Along with the Peritoneal Carcinomatosis Index, intraperitoneal-free cancer cells are a strong prognostic factor for patients treated with curative intent for colorectal peritoneal carcinomatosis by complete cytoreductive surgery. The presence of intraperitoneal-free cancer cells should lead to the consideration of different treatment strategies such as extensive intraperitoneal lavage, targeted intraperitoneal therapies, or repeated intraperitoneal chemotherapy.

Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with colon cancer at high risk of peritoneal carcinomatosis; the COLOPEC randomized multicentre trial

Background

The peritoneum is the second most common site of recurrence in colorectal cancer. Early detection of peritoneal carcinomatosis (PC) by imaging is difficult. Patients eventually presenting with clinically apparent PC have a poor prognosis. Median survival is only about five months if untreated and the benefit of palliative systemic chemotherapy is limited. Only a quarter of patients are eligible for curative treatment, consisting of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CR/HIPEC). However, the effectiveness depends highly on the extent of disease and the treatment is associated with a considerable complication rate.

These clinical problems underline the need for effective adjuvant therapy in high-risk patients to minimize the risk of outgrowth of peritoneal micro metastases. Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) seems to be suitable for this purpose. Without the need for cytoreductive surgery, adjuvant HIPEC can be performed with a low complication rate and short hospital stay.

Methods/Design

The aim of this study is to determine the effectiveness of adjuvant HIPEC in preventing the development of PC in patients with colon cancer at high risk of peritoneal recurrence. This study will be performed in the nine Dutch HIPEC centres, starting in April 2015. Eligible for inclusion are patients who underwent curative resection for T4 or intra-abdominally perforated cM0 stage colon cancer. After resection of the primary tumour, 176 patients will be randomized to adjuvant HIPEC followed by routine adjuvant systemic chemotherapy in the experimental arm, or to systemic chemotherapy only in the control arm. Adjuvant HIPEC will be performed simultaneously or shortly after the primary resection. Oxaliplatin will be used as chemotherapeutic agent, for 30 min at 42-43 °C. Just before HIPEC, 5-fluorouracil and leucovorin will be administered intravenously. Primary endpoint is peritoneal disease-free survival at 18 months. Diagnostic laparoscopy will be performed routinely after 18 months postoperatively in both arms of the study in patients without evidence of disease based on routine follow-up using CT imaging and CEA.

Discussion

Adjuvant HIPEC is assumed to reduce the expected 25 % absolute risk of PC in patients with T4 or perforated colon cancer to a risk of 10 %. This reduction is likely to translate into a prolonged overall survival.

Trial registration number

NCT02231086 (Clinicaltrials.gov)

Intraperitoneal chemotherapy as adjuvant treatment to prevent peritoneal carcinomatosis of colorectal cancer origin: a systematic review

Background:

Peritoneal carcinomatosis (PC) of colorectal cancer (CRC) origin is associated with poor outcome. This systematic review evaluates the available evidence about adjuvant (hyperthermic) intraperitoneal chemotherapy ((H)IPEC) to prevent the development of PC.

Methods:

A systematic search of literature was conducted in August 2013 in PubMed, Embase, and the Cochrane database for studies on (H)IPEC to prevent PC in patients who underwent curative surgery for primary CRC.

Results:

Seven comparative studies and five cohort studies were selected. Treatment schedules varied between repeated fluoropyrimidine-based IPEC administration in the ambulatory setting to intra-operative (H)IPEC procedures using mitomycin-C or oxaliplatin. The reported rates of major complications related to adjuvant (H)IPEC was low. Four out of five evaluable comparative studies reported a significant difference in the incidence of PC in favour of (H)IPEC. All three comparative studies reporting on survival after intra-operative (H)IPEC showed a significant survival benefit in favour of the experimental arm. Substantial heterogeneity in patient selection, treatment protocols, and treatment effect evaluation among studies was observed.

Conclusions:

The currently available evidence about adjuvant (H)IPEC in high-risk CRC is limited and subject to bias, but points towards improved oncological outcome and supports further randomised studies.

Intra-operative peritoneal lavage for colorectal cancer

Free cancer cells can be detected in peritoneal fluid at the time of colorectal surgery. Peritoneal lavage in colorectal surgery for cancer is not used in routine, and the prognostic significance of intraperitoneal free cancer cells (IPCC) remains unclear. Data concerning the technique of peritoneal lavage to detect IPCC and its timing regarding colorectal resection are scarce. However, positive IPCC might be the first step of peritoneal spread in colorectal cancers, which could lead to early specific treatments. Because of the important heterogeneity of IPCC determination in reported studies, no treatment have been proposed to patients with positive IPCC. Herein, we provide an overview of IPCC detection and its impact on recurrence and survival, and we suggest further multi-institutional studies to evaluate new treatment strategies.

Peritoneal carcinomatosis

Several gastrointestinal and gynecological malignancies have the potential to disseminate and grow in the peritoneal cavity. The occurrence of peritoneal carcinomatosis (PC) has been shown to significantly decrease overall survival in patients with liver and/or extraperitoneal metastases from gastrointestinal cancer. During the last three decades, the understanding of the biology and pathways of dissemination of tumors with intraperitoneal spread, and the understanding of the protective function of the peritoneal barrier against tumoral seeding, has prompted the concept that PC is a loco-regional disease: in absence of other systemic metastases, multimodal approaches combining aggressive cytoreductive surgery, intraperitoneal hyperthermic chemotherapy and systemic chemotherapy have been proposed and are actually considered promising methods to improve loco-regional control of the disease, and ultimately to increase survival. The aim of this review article is to present the evidence on treatment of PC in different tumors, in order to provide patients with a proper surgical and multidisciplinary treatment focused on optimal control of their locoregional disease.

Lack of prognostic significance of conventional peritoneal cytology in colorectal and gastric cancers: results of EVOCAPE 2 multicentre prospective study

AIM

In digestive cancers, the prognostic significance of intraperitoneal free cancer cells remains unclear (IPCC). The main objective of this study was to assess the prognostic significance of IPCC in colorectal and gastric adenocarcinoma. The secondary objectives were to evaluate the predictive significance of IPCC for the development of peritoneal carcinomatosis (PC) and to evaluate the prevalence of synchronous PC and IPCC.

METHODS

This was a prospective multicentre study. All patients undergoing surgery for a digestive tract cancer had peritoneal cytology taken. Patients with gastric and colorectal cancer with no residual tumour after surgery and no evidence of PC were followed-up for 2 years. The primary end point was overall survival.

RESULTS

Between 2002 and 2007, 1364 patients were enrolled and 956 were followed-up over 2 years. Prevalence of IPCC was 5.7% in colon cancer, 0.6% in rectal cancer and 19.5% in gastric cancer. The overall 2-year survival rate for patients with IPCC was 34.7% versus 86.8% for patients with negative cytology (p<0.0001). By multivariate analysis, IPCC was not an independent prognostic factor. No relationship between cytology and recurrence was found.

CONCLUSION

The presence of IPCC was not an independent prognostic and didn't add any additional prognostic information to the usual prognostic factors related to the tumour (pTNM and differentiation). Moreover the presence of IPCC detected with this method didn't appear to predict development of PC. Peritoneal cytology using conventional staining doesn't seem to be a useful tool for the staging of colorectal and gastric cancers.

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.

Early intervention for treatment and prevention of colorectal carcinomatosis: a plan for individualized care

The benefits that are reported in patients who have carcinomatosis from colorectal cancer increase as the extent of disease within the abdomen and pelvis decreases. To optimize treatments that involve cytoreductive surgery and perioperative chemotherapy, early intervention is necessary. Strategies to improve the results of carcinomatosis treatments include second-look surgery and hyperthermic intraperitoneal chemotherapy in patients at high risk for recurrence. Alternatively, the use of hyperthermic intraperitoneal chemotherapy can be used to treat or prevent carcinomatosis at the time of primary colorectal cancer resection in selected patients.

HIPEC in T4a colon cancer: a defendable treatment to improve oncologic outcome?

BACKGROUND

Adequate estimation of the potential benefits of 'adjuvant' hyperthermia and intraperitoneal chemotherapy (HIPEC) in T4 patients through assessment of the burden of peritoneal carcinomatosis (PC) in T4 tumors and the risk of PC as the only metastatic site.

PATIENTS AND METHODS

Analysis of prospectively collected data on patients who underwent surgery for colon cancer (Jan 2004-Jan 2007).

RESULTS

About 379 patients (M/F = 204/175) were included, with a median age of 71.8 years (range 35.4-95.0): 39 stage I, 126 stage II, 89 stage III, 116 stage IV disease (+9 with unknown stage). The median follow-up was 34.8months [range 0.0-79.4]. The 3- and 5-year overall survival rates (OS) were 68.4% (95% confidence interval (CI) 63.9%-72.4%) and 60.3% (95%CI 55.6%-64.7%). Relapse analysis was restricted to stages II-III T3 (N = 154) and T4 tumors (N = 19) with complete relapse data, of which 13.2% developed PC. PC has a detrimental effect on OS [HR 6.3 (95%CI: 3.1-13.0, P < 0.0001)]. 50% of T4a and 20% of T4b developed PC. The 1- and 3-year PC percentage was significantly lower for T3 (4.5% and 9.3%) than T4 tumors (15.6% and 36.7%) (P = 0.008). PC was the only metastatic site in 3/15 T3 [proportion 0.20, 95%CI (0.043-0.481)] and 5/8 T4 tumors with PC [proportion 0.625, 95%CI (0.245-0.915)] (P = 0.071).

CONCLUSIONS

T4a colon tumors have a significantly higher risk of developing PC. Twenty-five percent (5/19) of stages II-III T4 tumors develop PC as the only metastatic site. This could define the possible window of opportunity for adjuvant HIPEC to prevent PC.

Proactive management of peritoneal metastases from colorectal cancer: the next logical step toward optimal locoregional control

SUMMARY Although surgery for colorectal cancer has improved over the last decade, locoregional recurrence and peritoneal metastases continue as a mechanism of surgical treatment failure in 10–20% of patients. These patients have a dismal prognosis. Clinical information is available in order to identify patients who are at high risk for locoregional recurrence and peritoneal metastases. These patients, once identified, should be offered new treatment options shown to be of benefit in selected patients. Using perioperative chemotherapy at the time of colorectal cancer resection improves locoregional control and diminishes peritoneal metastases. Also, in patients at high risk, a proactive second-look surgery utilizing peritonectomy and hyperthermic intraperitoneal chemotherapy is of benefit, with reasonable morbidity and mortality.

Lack of prognostic role of pre- and postoperative peritoneal cytology and cytokeratin PCR-expression on local recurrence after curative anterior resection for mid-low rectal cancer

Local recurrence continues to be a major problem in rectal cancer. After cancer removal, detection of viable cancer cells could be useful to identify patients at risk for local recurrence. Thus, aim of the study was the detection of residual peritoneal cancer cells with a possible prognostic role for local recurrence. Twenty-nine patients were operated (R0) for low (extraperitoneal) rectal cancer, without neoadjuvant radiochemotherapy. Before and immediately after cancer removal, a peritoneal lavage was done to evaluate by RT-PCR the cytokeratin 20 mRNA on isolated cells and in order to detect cancer cells by the Thin-prep test. After a median follow-up of 39 months, 5 patients died (17%), one for non-cancer-related disease, two (7%) for local recurrence and peritoneal carcinosis, and two for distant metastases. Preoperative cytology with Thin-prep test was positive in 4 patients (14%), while postoperative peritoneal cytology was positive only in 1 patient, different from the previous. No patient developed local or distal recurrence and all were disease-free at the end of the follow-up. RT-PCR analysis was positive on the peritoneal lavage after cancer removal in 11 patients. One died for unrelated cause and no one developed local recurrences. Local recurrence occurred in only 1 of the 2 patients with positive RT-PCR analysis on the first lavage and negative on the second lavage. Our study demonstrates a not important prognostic role of Thin-prep test and RT-PCR of cytokeratin 20 mRNA on the detection of patients at risk for local recurrence after curative resection of rectal cancer.

Revised guidelines for second-look surgery in patients with colon and rectal cancer

Proper indications for a second surgical intervention in patients with colorectal cancer have always been a controversial subject. Surgeons find benefit in a second-look operation where a limited extent of cancer is discovered and resected with negative margins. However, a negative exploratory laparotomy or an intervention that is unable to achieve an R0 resection provides little or no benefit. Unfortunately, this type of intervention may place the patient in a worse condition, leading to morbidity or mortality. This manuscript attempts to define clinical parameters of primary colorectal cancer that are associated with a pattern of recurrence and that can be definitively addressed by second-look surgery. Also, new surgical technologies that may assist in achieving a potentially curative resection of local-regional recurrence are described. Cytoreductive surgery with peritonectomy and perioperative intraperitoneal chemotherapy with hyperthermia is presented as a new treatment option for reoperative surgery. A new management plan utilized in patients at high risk for local-regional recurrence may result in a high likelihood of conversion of a second-look cancer-positive patient to a long-term survivor.

Assessment of Serosal Invasion and Criteria for the Classification of Pathological (p) T4 Staging in Colorectal Carcinoma: Confusions, Controversies and Criticisms

Transmural spread by colorectal carcinoma can result in tumor invasion of the serosal surface and, hence, more likely dissemination within the peritoneal cavity and potentially to additional metastatic sites. The adverse prognostic significance of serosal invasion is widely accepted and its presence may be considered an indication for chemotherapy in patients with node negative disease. However, controversy persists regarding the most appropriate criteria for diagnosis and there are also practical difficulties associated with histological assessment in some cases. Therefore, serosal invasion may be under-diagnosed in a significant proportion of tumors, potentially leading to sub-optimal treatment of high-risk patients. The examination of multiple microscopic sections combined with ancillary studies such as cytology preparations, elastin stains, and immunohistochemistry may prove beneficial in selected problematic cases, but these are not used routinely. The relative prognostic significance of serosal invasion and of direct tumor spread to other organs, both of which are incorporated within the pT4 category of the AJCC/UICC TNM staging system, remains unclear. Further studies are required to demonstrate whether recent adjustments to the TNM staging of pT4 tumors are appropriate.

Second-look surgery for colorectal cancer: revised selection factors and new treatment options for greater success

Proper indications for second-look surgery in patients with colorectal cancer have always been a controversial subject. The surgical literature suggests benefit in a reoperation, where a limited extent of cancer is discovered and then resected with negative margins. However, patients are often subjected to a negative exploratory laparotomy or an intervention that is unable to achieve an R-0 resection; in these circumstances, little or no benefit occurs. Unfortunately, an unsuccessful repeat intervention may place the patient in a worse condition, especially if morbidity occurs. This paper seeks to identify the clinical parameters of a primary colorectal cancer and a followup plan that are associated with cancer recurrence that can be definitively addressed by the second look surgery. New surgical technologies, including cytoreductive surgery with peritonectomy and perioperative intraperitoneal chemotherapy with hyperthermia, are suggested for use in this group of patients. This new management strategy used in patients with local-regional recurrence may result in a high proportion of patients converted from a second-look positive patient to a long-term survivor.

Effects of intraperitoneal chemotherapy with mitomycin C on the prevention of peritoneal recurrence in colorectal cancer patients with positive peritoneal lavage cytology findings

BACKGROUND

The detection of intraperitoneal free cancer cells in colorectal cancer (CRC) patients is associated with a poorer prognosis. The aim of this study was to investigate the effects of intraperitoneal chemotherapy (IPC) with mitomycin C (MMC) on preventing peritoneal recurrence in CRC patients with positive peritoneal lavage cytology findings.

METHODS

A total of 52 CRC patients who had no clinically confirmed peritoneal dissemination and whose status of peritoneal lavage cytology was positive were investigated. Conventional peritoneal lavage cytology was performed. Overall, 31 of the 52 patients (59.6%) were administered IPC with MMC. Before closure of the abdomen, 4 silicon catheters were inserted into peritoneal cavity. After closure, the perfusate (diluting 20 mg MMC with 500 ml saline) was instilled from the catheter, and all catheters were clumped. All catheters were opened 1 h later.

RESULTS

The mean follow-up period was 83.1 months. According to univariate analyses of all 52 patients and the subgroup of 36 patients with stage II or III tumors, patients with IPC had a significantly better peritoneal recurrence-free survival and cancer-specific survival than patients who did not receive IPC (P < 0.005). In multivariate analysis, IPC remained an independent prognostic factor for peritoneal recurrence-free survival in all patients.

CONCLUSIONS

It appears that IPC with MMC is an effective treatment to prevent peritoneal recurrence and prolong the cancer-specific survival in CRC patients without peritoneal dissemination, but who have positive peritoneal lavage cytology. It is necessary to verify the effectiveness of IPC with MMC in a prospective trial.

Evaluation of intraperitoneal lavage cytology before colorectal cancer resection

PURPOSE

The aim of this study was to assess the usefulness of intraperitoneal lavage cytology (lavage Cy) status before the resection of colorectal cancer as a predictive factor of peritoneal recurrence.

MATERIALS AND METHODS

The lavage Cy-positive [lavage Cy (+)] rate, peritoneal recurrence rate, and 5-year survival rate were examined in 298 cases of colorectal cancer in relation to various clinicopathological factors.

RESULTS

The overall lavage Cy (+) rate was 6.0%. The lavage Cy (+) rate within the group with peritoneal and hepatic metastases was significantly higher than that in the group without metastases (46.7% vs. 3.9% and 26.9% vs. 4.0%, respectively). The lavage Cy (+) rate was not significantly associated with any of the clinicopathological factors examined. The peritoneal recurrence rate was higher in the lavage Cy (+) group than in the lavage Cy-negative [lavage Cy (-)] group, although the difference was not statistically significant. There was no significant difference in survival, regardless of the lavage Cy status, among the 263 patients who underwent curative resection.

CONCLUSION

The lavage Cy status before resection was not a useful predictive factor of peritoneal recurrence in cases of colorectal cancer.

Long-term prognostic value of conventional peritoneal lavage cytology in patients undergoing curative colorectal cancer resection

PURPOSE

Free malignant cells in the peritoneal cavity might play a role in the metastasis process. However, this phenomenon needs further elucidation. The aims of this study were to investigate the frequency of free cancer cells detected on cytologic examination of lavage fluid after peritoneal washing in patients undergoing curative surgery for colorectal cancer, to explore risk factors for exfoliation of cancer cells into the peritoneal cavity, and to evaluate the influence peritoneal lavage cytology as a prognostic tool.

METHODS

Peritoneal lavage was performed in 697 patients undergoing curative resection of colorectal cancer. Before the manipulation of the tumor, 100 mL of physiologic saline solution was administered into the abdominal cavity and the fluid was collected for cytologic examination. Specimens were classified as positive if at least one cancer cell was detected.

RESULTS

The mean follow-up period was 90.5 months. Overall, 15 (2.2%) of the 697 patients had positive results. Four characteristics were identified as risk factors for exfoliation of cancer cells into the peritoneal cavity: 1) depth of invasion, 2) regional lymph nodes, 3) lymphatic invasion, and 4) venous invasion. In univariate analyses of all 697 patients and the subgroup of 374 patients with pT3 or T4 tumors, patients with positive cytology findings had significantly worse disease-free and cancer-specific survival than patients with negative cytology findings (P < 0.001). On multivariate analysis, peritoneal cytology remained an independent predictor of cancer-specific survival in all patients and in patients with pT3 or pT4 tumors. Only peritoneal cytology was a significant prognostic factor for peritoneal recurrence (P < 0.0001).

CONCLUSION

Conventional peritoneal cytology is a useful prognostic tool in patients undergoing curative surgery for colorectal cancer and may be helpful in making decisions whether to select intraperitoneal or systemic chemotherapy.

Peritoneal minimal residual disease in colorectal cancer: mechanisms, prevention, and treatment

Roughly one in five patients with colorectal cancer develops peritoneal minimal residual disease after surgical resection, and about one in seven patients develops peritoneal carcinomatosis. By contrast with the vast body of research addressing haematogenous metastasis, little is known about the biology of peritoneal spread of colorectal cancer. The development of peritoneal carcinomatosis involves well-defined steps including cell shedding and transport, adhesion to the mesothelial layer, invasion of and proliferation into the submesothelial stroma, and potential access to the systemic circulation. In this Review, we summarise the molecular mechanisms and potential preventive measures associated with each step of the peritoneal metastatic cascade.