Peritoneal cytology in the determination of free tumour cells within the abdomen in colon cancer

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.

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.

Incidence and Prognostic Value of Lavage Cytology in Colorectal Cancer

BACKGROUND

Lavage cytology is a method to detect cancer cells released within the abdominal cavity. It has been widely utilized, in particular, for gastric cancer. However, its clinical significance has not yet been determined in colorectal cancer.

OBJECTIVE

This study aimed to investigate the frequency of lavage cytology positivity and its influence on the prognosis of patients with colorectal cancer.

DESIGN

This is a single-institution retrospective observational study.

SETTING

This study was conducted at a comprehensive cancer center.

PATIENTS

We retrospectively analyzed 3135 colorectal cancer cases from 2007 to 2013 at our institution. Intraoperative peritoneal washing cytology was performed just after the start of the operation. Fluids were centrifuged for 5 minutes at 2500 rotations per minute, cell pellets were smeared on microscope glass slides, and Papanicolaou staining was performed.

MAIN OUTCOME MEASURES

The primary outcome was the 5-year overall survival rate. The secondary outcome was the 5-year recurrence rate.

RESULTS

Lavage cytology positivity was detected in 19 (2.0%) and 86 (16.9%) cases of stage III and IV colorectal cancer; however, no positive cases were found in stage I and II colorectal cancer. Lavage cytology positivity was an independent prognostic factor in stage III and IV colorectal cancer in the multivariate analysis (5-year mortality HR 3.59 [1.69-7.64] in stage III, 2.23 [1.15-4.31] in stage IV). The prognosis of the 5-year survival rate was significantly worse in the lavage cytology-positive group in stages III and IV. In terms of recurrence, the results of the lavage cytology-positive group in stage III were similar to those of the lavage cytology-positive/negative group in stage IV (73.7%, 70.0%, and 75.0%).

LIMITATIONS

This study was limited by its retrospective study design.

CONCLUSIONS

Lavage cytology positivity is an independent prognostic and regulatory factor of stage IV colorectal cancer. See Video Abstract at http://links.lww.com/DCR/B770.INCIDENCIA Y VALOR PRONÓSTICO EN LA CITOLOGÍA DEL LAVADO PERITONEAL EN CÁNCER COLORECTALANTECEDENTES:La citología del lavado peritoneal es un método para detectar células cancerosas liberadas dentro de la cavidad abdominal. Se ha utilizado ampliamente, en particular para el cáncer gástrico. Sin embargo, aún no se ha determinado su importancia clínica en el cáncer colorrectal.OBJETIVO:Este estudio tuvo como objetivo investigar la frecuencia de positividad de la citología del lavado y su influencia en el pronóstico de los pacientes con cáncer colorrectal.DISEÑO:Este fue un estudio observacional retrospectivo de una sola institución.DISENTORNO CLÍNICO:El estudio se llevó a cabo en un centro oncológico integral.PACIENTES:Analizamos retrospectivamente 3.135 casos de cáncer colorrectal desde 2007 hasta 2013 en nuestra institución. La citología de lavado peritoneal intraoperatorio se realizó inmediatamente después del inicio de la operación. Los fluidos se centrifugaron durante 5 min a 2.500 rpm, los sedimentos celulares se extendieron sobre portaobjetos de vidrio de microscopio y se realizó la tinción con Papanicolaou.DISPRINCIPALES MEDIDAS DE VALORACIÓN:El primer resultado fueron las tasas de supervivencia general a 5 años. El segundo resultado las tasas de recurrencia a los 5 años.RESULTADOS:Se detectó positividad en la citología de lavado en 19 (2,0%) y 86 (16,9%) casos de cáncer colorrectal en estadio III y IV, respectivamente; sin embargo, no se encontraron casos positivos en el cáncer colorrectal en estadio I y II. La positividad de la citología de lavado fue un factor pronóstico independiente en el cáncer colorrectal en estadio III y IV en el análisis multivariado [cociente de riesgo de mortalidad a 5 años 3,59 (1,69-7,64), en estadio III, 2,23 (1,15-4,31), en estadio IV]. El pronóstico de la tasa de supervivencia a 5 años fue significativamente peor en el grupo con citología de lavado positiva en los estadios III y IV. En cuanto a la recurrencia, los resultados del grupo de lavado con citología positiva en el estadio III fueron similares a los del grupo de lavado con citología positiva / negativa en el estadio IV (73,7%, 70,0% y 75,0%).LIMITACIONES:Este estudio estuvo limitado por su diseño de estudio retrospectivo.CONCLUSIONES:La positividad de la citología de lavado es un factor pronóstico y regulador independiente del cáncer colorrectal en estadio IV. Consulte Video Resumen en http://links.lww.com/DCR/B770. (Traducción- Dr. Ingrid Melo).

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.

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.

Prognostic significance of positive peritoneal cytology in resectable pancreatic cancer: a systemic review and meta-analysis

Although peritoneal cytology has been used to determine pancreatic cancer staging for more than three decades, its prognostic significance in potentially resectable pancreatic cancer is inconclusive. We therefore conducted this meta-analysis to investigate the impact of peritoneal cytology status on the clinicopathological features and survival outcomes in potentially resectable pancreatic cancer. Ten studies were identified for this meta-analysis after searching the PubMed, Web of Science and China National Knowledge Infrastructure (CNKI) electronic databases. Our results showed that positive peritoneal cytology was associated with tumor size (OR 11.65, P = 0.001), tumor location (OR 0.37, P = 0.000), serosal invasion (OR 3.89, P = 0.000), portal vein invasion (OR 1.82, P = 0.016), lymph vessel invasion (OR 2.71, P = 0.026), T stage (OR 2.65, P = 0.037) and N stage (OR 2.34, P = 0.001) in resectable pancreatic cancer. Patients with positive peritoneal cytology demonstrated poor overall survival (OS; HR 3.18, P = 0.000) and disease-free survival (DFS; HR 2.88, P = 0.000) times. Based on our meta-analysis, we conclude that positive peritoneal cytology is an indicator of advanced stage pancreatic cancer with a poor prognosis; hence, radical resection should not be performed on these patients.

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.

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.

Prognostic significance of detection of microscopic peritoneal disease in colorectal cancer: a systematic review

BACKGROUND

Free intraperitoneal tumour cells are an independent indicator of poor prognosis, and are encorporated in current staging systems in upper gastrointestinal cancers, but not colorectal cancer. This systematic review aimed to evaluate the role and prognostic significance of positive peritoneal lavage in colorectal cancer.

METHODS

A search was undertaken of PUBMED/Medline and Cochrane databases for English language articles from 1990 to 2012 using a predefined search strategy. Both detection of free tumour cells and/or detection of tumour-associated antigens in peritoneal lavage fluid were considered a positive lavage. Primary endpoints were rates of positive lavage, recurrence and survival.

RESULTS

Of 3805 articles identified by title, 18 met inclusion criteria (n = 3197 patients, 59.5% colon, 40.5% rectal cancer). There was heterogeneity across studies in method of detection of peritoneal disease with 7 studies using more than one method (conventional cytology (14 studies), immunological techniques (6 studies), molecular techniques (4 studies)). The rate of positive lavage varied from 2.1% to 52% across studies, with a weighted mean rate of positive lavage of 13.17% overall (95% CI 12.74-13.59). In 10 studies (n = 2017) positive peritoneal lavage was associated with worse survival, and with increased recurrence in 12 (n = 2371). Clinicopathological factors frequently associated with positive lavage included macroscopic peritoneal disease, increasing tumour stage and nodal disease.

CONCLUSION

Positive peritoneal lavage is a negative prognostic factor in colorectal cancer. However, its utility in staging colorectal cancer is currently limited by wide variation in rates of positive lavage between studies due to differences in methods of peritoneal lavage fluid analysis.

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.

Prognostic significance of peritoneal tumour cells identified at surgery for colorectal cancer

BACKGROUND

The prognostic significance of intraperitoneal tumour cells (IPCs) in colorectal cancer is not clear. This study aimed to determine whether detection of IPCs could be used a prognostic marker for selecting patients at high risk of recurrence.

METHODS

The study included 226 patients with colorectal cancer who underwent elective resection. Clinical variables, including the presence of IPCs, were analysed for their prognostic significance.

RESULTS

Thirty-three patients (14.6 per cent) were positive for IPCs. Univariable analysis indicated that the presence of IPCs was a significant prognostic factor in patients with stage III colorectal cancer; the 5-year disease-specific survival rate was 14 per cent in IPC-positive patients versus 79 per cent in those without IPCs (P < 0.001). Multivariable analysis showed that IPC positivity was the most robust prognostic factor in stage III disease (hazard ratio 2.2; P = 0.003), whereas nodal category (N1 or N2) showed no significant association with prognosis. In addition, IPCs were associated with haematogenous recurrence (P = 0.004) rather than peritoneal or local recurrence (P = 0.077) in patients with stage III disease.

CONCLUSION

The presence of IPCs is a significant prognostic factor in patients with stage III colorectal cancer.

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

BACKGROUND

Accurate staging of colorectal cancer is important for predicting prognosis and guiding treatment. This study uses meta-analysis to investigate if the pre- or post-resection detection of intraperitoneal free cancer cells can predict recurrence in patients undergoing curative colorectal cancer surgery.

METHODS

A literature search was performed on all studies between January 1990 and July 2007 comparing the detection of intraperitoneal free cancer cells either pre- or post-resection with prognosis in colorectal cancer. The following prognostic outcomes were meta-analyzed: overall recurrence rate and local recurrence rate. A random-effect model was used and heterogeneity was assessed.

RESULTS

Nine studies reporting on a total of 1182 subjects matched the selection criteria. Free cancer cells were detected prior to tumor resection in 125/822 (15.2%) of patients and following resection in 64/533 (12%) of patients. Preresection, the absence of tumor cells was associated with a lower overall recurrence (25.2%) compared to the presence of tumor cells [46.4%, odds ratio (OR) = 0.41, confidence interval (CI) 0.19-0.88]; as well as a significantly lower local recurrence (12.2% versus 21.1%, OR = 0.42, CI 0.21-0.82). Postresection, the absence of tumor cells also resulted in significantly lower overall recurrence (17.3%) when compared to the presence of tumor cells (52.6%, OR = 0.07, CI 0.03-0.18).

CONCLUSIONS

The detection of intraperitoneal free cancer cells is associated with higher recurrence and poorer prognosis. Use of these techniques can identify patients at higher recurrence risk. This could be particularly valuable in stage II disease to identify patients who may benefit from adjuvant chemotherapy.

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.

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.

TNM residual tumor classification revisited

BACKGROUND

For cancer patients, prognosis is strongly influenced by the completeness of tumor removal at the time of cancer-directed surgery or disease remission after nonsurgical treatment with curative intent. These parameters define the relative success of definitive treatment and can be codified by an additional subclassification within the TNM system, the residual tumor (R) classification. Despite the importance of residual tumor status in designing clinical management after treatment, misinterpretation and inconsistent application of the R classification frequently occur that diminish or abrogate its clinical utility.

METHODS

An analysis of the relevant literature regarding the use and prognostic importance of the R classification was undertaken.

RESULTS

In the current study, the prognostic importance of the R classification for different kinds of tumors is discussed. Problems that arise in using the R classification are described. Special issues regarding the use of the R classification are addressed.

CONCLUSIONS

The R classification is a strong indicator of prognosis and facilitates the comparison of treatment results if applied in a consistent manner. Uniform use and interpretation of this classification is essential for the standardization of posttreatment data collection.

Cytology of peritoneal lavage performed during staging laparoscopy for gastrointestinal malignancies: is it useful?

OBJECTIVE

To evaluate the potential benefit of cytology of the peritoneal lavage obtained during diagnostic laparoscopy for staging gastrointestinal (GI) malignancies.

SUMMARY BACKGROUND DATA

Peritoneal lavage is a simple procedure that can be performed during laparotomy for GI tumors. Tumor cells in the lavage fluid are thought to indicate intraperitoneal tumor seeding and to have a negative effect on survival. For this reason, peritoneal lavage is frequently added to diagnostic laparoscopy for staging GI malignancies.

METHODS

Patients who underwent peritoneal lavage during laparoscopic staging for GI malignancies between June 1992 and September 1997 were included. Lavage fluids were stained using Giemsa and Papanicolaou methods. Cytology results were correlated with the presence of metastases and tumor ingrowth found during laparoscopy and with survival.

RESULTS

Cytology of peritoneal lavage was performed in 449 patients. Tumor cells were found in 28 patients (6%): 8/87 with an esophageal tumor, 2/32 with liver metastases, 11/72 with a proximal bile duct tumor, 7/236 with a periampullary tumor, and none in 7 and 15 patients with a primary liver tumor or pancreatic body or tail tumor, respectively. In 19 of the 28 patients (68%) in whom tumor cells were found, metastatic disease was detected during laparoscopy, and 3 of the 28 patients had a false-positive (n = 1) or a misleading positive (n = 2) lavage result. Therefore, lavage was beneficial in only 6/449 patients (1.3%); in these patients, the lavage result changed the assessment of tumor stage and adequately predicted irresectable disease. Univariate analysis showed a significant survival difference between patients in whom lavage detected tumor cells and those in whom it did not, but multivariate analysis revealed that these survival differences were caused by metastatic or ingrowing disease.

CONCLUSION

Cytology of peritoneal lavage with conventional staining should no longer be performed during laparoscopic staging of GI malignancies because it provides an additional benefit in only 1.3% of patients and has limited prognostic value for survival in this group of patients.