Prognostic factors for peritoneal carcinomatosis originating from colorectal cancer: an analysis of 921 patients from a multi-institutional database

Factors Affecting the Prognosis after Primary Tumor Resection for Patients with Metastatic Colorectal Cancer with Synchronous Peritoneal Metastasis: A Multi-center, Prospective, Observational Study

Objectives

To clarify the risk factors affecting prognosis after primary tumor resection (PTR) in patients with metastatic colorectal cancer with synchronous peritoneal metastasis (mCRC-SPM).

Methods

Patients were enrolled prospectively in the JSCCR project "Grading of Peritoneal Seeding in Colorectal Cancer." Factors that may influence overall survival-age, sex, location of the primary tumor, lymph node metastasis, presence of liver metastasis, degree of peritoneal metastasis, peritoneal cancer index (PCI), cancer cure, and postoperative chemotherapy-in the PTR group were examined using multivariate analysis.

Results

Of the 133 enrolled patients with mCRC-SPM, 112 patients underwent PTR. Among them, 26 (23.2%) had mCRC-SPM of grade P1, 47 (42.0%) of P2, and 39 (34.8%) of P3. The median PCI was 4 (range, 1-28); no surgery-related deaths occurred. Postoperative complications of Clavien-Dindo classification ≥grade 2 were observed in 20 (17.9%) patients. R0 surgery became more difficult as the degree of dissemination increased, and the PTR group had a significantly better prognosis than the non-PTR group. In the multivariate analysis, age ≥75 years, rectal cancer, presence of liver metastasis, higher PCI, non-curative resection, and non-treatment with systemic chemotherapy were associated with poor prognosis in patients after PTR.

Conclusions

In patients with mCRC-SPM, postoperative complications are infrequent for P1 with localized peritoneal dissemination, and PTR may be considered as aggressive treatment. Factors including age ≥75 years, rectal cancer, presence of liver metastasis, increased PCI, non-curative resection, and non-treatment with systemic chemotherapy are associated with a reduced survival benefit from PTR.

Prognostic Impact of Potentially Curative Resection for Synchronous Peritoneal Carcinomatosis with Lavage Cytology Positivity in Colorectal Cancer: A Retrospective Observational Study

Objectives

Although curative resection for synchronous peritoneal carcinomatosis has been reported to improve prognosis, cases with positive intraoperative lavage cytology have not been reported. In this study, we investigated the prognostic value of potentially curative resection based on colorectal cancer and lavage cytology positivity in patients with synchronous peritoneal carcinomatosis.

Methods

We retrospectively evaluated 72 patients who underwent intraoperative lavage cytology and one-stage potentially curative resection of primary and metastatic lesions (lavage cytology-positive, n = 21; lavage cytology-negative, n = 51) between July 2004 and December 2019. We compared the 5-year overall survival and 3-year recurrence rates between the lavage cytology-positive and lavage cytology-negative groups.

Results

No significant differences were observed in the 5-year overall survival (48.2% vs. 45.5%, P = 0.924) or 3-year recurrence rates (74.5% vs. 62%, P = 0.143) between the two groups. Univariate analysis for 3-year recurrence revealed that lavage cytology-positive status was not an explanatory variable (hazard ratio: 1.552, 95% confidence interval: 0.83-2.902, P = 0.169). Multivariate analysis identified colon cancer as an independent risk factor of recurrence.

Conclusions

In resectable cases, the resection of synchronous peritoneal carcinomatosis from colorectal cancer can be considered even if intraoperative lavage cytology is positive.

RAS mutant transverse colon cancer with multiple liver metastases achieving long-term disease-free survival with postoperative maintenance therapy with aflibercept + FOLFIRI and four repeated radical resections: a case report

BACKGROUND

Management of patients with colorectal liver metastases (CRLMs) requires a multidisciplinary approach. For patients with progression of RAS mutant tumors, the choice of angiogenesis inhibitors can be controversial. Here, we report a patient with RAS mutant CRLMs achieving long-term disease-free survival with repeated R0 resections and perioperative treatment, especially aflibercept + FOLFIRI (5-fluorouracil, levofolinate, irinotecan), which may have prevented long-term recurrence.

CASE PRESENTATION

The patient was a 37 year-old woman diagnosed with RAS mutant transverse colon cancer with 19 LMs. As the metastases were limited to the liver, we introduced systemic chemotherapy aiming at conversion surgery. After six cycles of bevacizumab + FOLFOXIRI (5-fluorouracil, levofolinate, oxaliplatin, irinotecan), we performed partial hepatectomy for all LMs, and left hemicolectomy for the primary tumor after another four cycles of bevacizumab + FOLFIRI. Three months after surgery, the patient presented with massive ovarian metastases with carcinomatous ascites. We conducted bilateral oophorectomy, and initiated aflibercept + FOLFIRI therapy considering the possibility of resistance to bevacizumab. The patient was recurrence-free for 2 years during aflibercept + FOLFIRI treatment. After its discontinuation, two distant metastases developed. Both were resectable and the patient achieved recurrence-free survival of 2 years and 3 months after the last operation (6 years since initiation of treatment), without additional chemotherapy.

CONCLUSIONS

We believe that multidisciplinary treatment aimed at complete resection could lead to long-term survival even in patients with repeated recurrence of CRLMs. Aflibercept + FOLFIRI could be effective in controlling metastasis of RAS mutant colon cancer even after treatment with bevacizumab.

Cytoreductive surgery without intra-peritoneal chemotherapy for metachronous colorectal peritoneal metastases

BACKGROUND

Cytoreductive surgery and chemotherapy reportedly improve the prognosis of patients with metachronous peritoneal metastases. However, the types of peritoneal metastases indicated for cytoreductive surgery remains unclear. Therefore, we aimed to clarify the category of cases for which cytoreductive surgery would be effective and report the prognosis associated with cytoreductive surgery for metachronous peritoneal metastases.

METHODS

This study included 52 consecutive patients who underwent cytoreductive surgery for metachronous peritoneal metastases caused by colorectal cancer between January 2005 and December 2018 and fulfilled the selection criteria. The median follow-up period was 54.9 months. Relapse-free survival was calculated as the time from cytoreductive surgery of metachronous peritoneal metastases to recurrence. Overall survival was defined as the time from cytoreductive surgery of metachronous peritoneal metastases to death or the end of the follow-up period.

RESULTS

The 5-year relapse-free survival rate was 30.0% and the 5-year overall survival rate was 72.3%. None of the patients underwent hyperthermic intraperitoneal chemotherapy. The analysis indicated no potential risk factors for 5-year relapse-free survival. However, for 5-year overall survival, the multivariate analysis revealed that time to diagnosis of metachronous peritoneal metastases of < 2 years after primary surgery (hazard ratio = 4.1, 95% confidence interval = 2.0-8.6, p = 0.0002) and number of metachronous peritoneal metastases ≥ 3 (hazard ratio = 9.8, 95% confidence interval = 2.3-42.3, p = 0.002) as independent factors associated with a poor prognosis.

CONCLUSIONS

Long intervals of more than 2 years after primary surgery and 2 or less metachronous peritoneal metastases were good selection criteria for cytoreductive surgery for metachronous peritoneal metastases from colorectal cancer.

Effect of adjuvant chemotherapy after curative resection of colorectal cancer peritoneal metastasis

PURPOSE

Several guidelines have recommended surgical resection for localized peritoneal metastases, but the prognosis remains poor. In addition, the efficacy of adjuvant chemotherapy (AC) after curative resection is under debate. The present study compared long-term outcomes between curative and non-curative resection and evaluated the effects of AC after curative resection.

METHODS

Using a multicenter database, we retrospectively reviewed 123 colorectal cancer patients with peritoneal metastases between April 2016 and December 2021. Of these patients, 49 underwent curative resection, and 74 underwent non-curative resection.

RESULTS

The frequency of broad metastases was lower in the curative resection group (8.2%) than in the non-curative resection group (43.2%, p < 0.001). Among all patients, 5-year overall survival rate was higher in the curative resection group (43.0%) than in the non-curative resection group (7.3%, p = 0.004). Among patients who underwent curative resection, 5-year overall survival rate was significantly higher in the AC group (48.2%) than in the non-AC group (38.1%, p = 0.037). Multivariate analysis of all patients revealed pathological N status and non-curative resection as independent predictors of overall survival. In patients who underwent curative resection, advanced age was an independent predictor of relapse-free survival, and AC was an independent predictor of overall survival.

CONCLUSION

This multicenter study of colorectal cancer patients with peritoneal metastases revealed that prognosis was more favorable for curable cases than for non-curable cases. Prognosis was more favorable in the AC group than in the non-AC group after curative resection.

Clinical outcomes of curative surgical resection of peritoneal metastasis in patients with colorectal cancer: A long-term follow-up study

INTRODUCTION

Colorectal cancer with peritoneal metastasis (PM) has been considered a non-curative disease. PM is associated with reduced overall survival (OS) and worse prognosis compared with metastasis at other sites. We aimed to investigate the treatment outcome and recurrence after curative resection of colorectal PM during a long-term follow-up.

METHODS

Patients who were diagnosed with colorectal PM and underwent surgery between December 2001 and December 2019 were included (n = 309). Curative resection was defined as PM resection without residual disease after surgery (complete macroscopic resection).

RESULTS

Of 309 patients, 208 (67.8%) had PM as an initially metastatic disease. Curative (R0/1) resection was achieved in 155 (50.2%) patients, while non-curative operation (R2 resection or palliative operation including colostomy) was performed in 154 (49.8%) patients. Compared with patients who underwent non-curative operation, those with curative resection more often had a single PM on preoperative imaging (34.2% vs. 20.8%, p = 0.011) and postoperative results (59.4% vs. 22.7%, p < 0.001) and less often had concurrent metastasis (distant lymph node, liver, or lung) at the time of surgery (p < 0.001). During a median follow-up of 90.4 months, 80.6% (125/155) patients had recurrence in the curative resection group; the peritoneum was the most common site (56.0%). The median OS was 47.7 months (95% CI, 39.2-56.2) in the curative resection group and 24.8 months (95% CI, 20.8-28.9) in the non-curative resection group, respectively (p < 0.001). In particular, twenty-six patients without recurrence showed long-term survival after curative resection (median OS, 87.1 months; range, 40.1-127.5).

CONCLUSION

Surgical resection can be considered for selected patients with colorectal PM because a significant number of them could seize the cure changes during their treatment continuum.

Treatment Outcome of Resection of Disseminated Peritoneal Metastases from Colorectal Cancer

AIM

To show the treatment outcomes of disseminated nodule resection for peritoneal metastasis of colorectal cancer and describe the details of cured cases.

PATIENTS AND METHODS

From January 2001 to December 2016, patients who underwent disseminated nodule resection of colorectal adenocarcinoma with no macroscopic residual tumor in our institution were retrospectively analyzed for clinicopathological factors associated with prognosis.

RESULTS

Forty-one cases were included in this study. The 3-year relapse-free survival was 12.5%, and the 5-year overall survival was 38.4%. In a multivariate analysis, lack of post-operative adjuvant chemotherapy and pre-operative carbohydrate antigen 19-9 over 100 IU/l were extracted as independent factors associated with short relapse-free survival, respectively. Among 41 cases, 32 were followed-up 5 years after surgery and five (15.6%) survived without relapse and were regarded as 'cured'.

CONCLUSION

More than a few cases of colorectal peritoneal metastasis, which is thought to be difficult to cure, were cured by resection of disseminated nodules without resorting to highly invasive treatment.

Prognostic Impact of Curative Resection for Peritoneal Recurrence of Colorectal Cancer

BACKGROUND

Peritoneal recurrence (PR) of colorectal cancer is a poor prognostic factor but may be treatable by curative resection. We investigated the efficacy of this treatment and identified risk factors for postoperative recurrence.

METHODS

The subjects were patients who underwent radical surgery for colorectal cancer between January 2006 and March 2014. Those with PR were retrospectively reviewed. Prognostic factors for overall survival (OS) and risk factors for postoperative recurrence were identified.

RESULTS

Among 2256 patients, 66 had PR (2.9%). Surgical resection of PR was performed in 41 patients. Curative resection was achieved macroscopically in 38 cases without diffuse metastases in the peritoneum distant from the primary tumor and with a peritoneal cancer index < 10. In multivariate analysis, curative resection was a significant prognostic factor [hazard ratio (HR) 0.198] for better 5-year OS compared with cases without curative resection (68.7% vs. 6.3%, P < 0.001). In 28 cases with concurrent metastasis, curative resection significantly improved 5-year OS compared with no curative resection (78.7% vs. 0%, P = 0.008). In the 38 patients with curative resection, the 3-year recurrence-free survival rate was 21.4%. In multivariate analysis, concurrent metastasis was a significant risk factor [HR 3.394] for postoperative recurrence, and cases with concurrent metastasis more frequently had recurrence within 2 years after curative resection.

CONCLUSIONS

Curative resection improved the prognosis in patients with limited and resectable PR of colorectal cancer with or without concurrent metastasis. However, recurrence after curative resection was common and concurrent metastasis was a risk factor for this recurrence.

Verifying the M1c category of CRC: analysis of the data from a Japanese multi-institutional database

BACKGROUND/AIMS

In the TNM classification 8th edition, colorectal cancer (CRC) with peritoneal metastasis, one of the most poor prognostic factors, is classified as M1c (stage IVC), regardless of the presence/absence of other distant metastasis. Several cases with peritoneal metastasis have been successfully managed by surgical treatment; therefore, there is need to give more consideration for uniform differentiation of peritoneal metastasis. This study was aimed at verifying the classification of M1c in CRC.

MATERIALS AND METHODS

Data from a multi-institutional retrospective cohort of 2929 CRC patients who were diagnosed as having stage IV CRC from 1997 to 2007 were analyzed. Peritoneal metastasis alone was defined as M1c1 and peritoneal metastasis with other organ metastasis was defined as M1c2.

RESULTS

The 3-year OS of patients with M1c1 was significantly higher than that of patients with M1b (25.6% vs. 18.1%; HR 0.77; 95% confidence interval (CI) 0.65-0.92; p = 0.005); in particular, the prognosis of patients with M1c1 with localized peritoneal metastasis and R0 resection was equivalent to that of patients with M1a (3-year OS 40.5% vs. 39.2%, p = 0.41). On the other hand, among the stage IV cases, patients with M1c2 had a low R0 resection rate (5.9%) and the worst prognosis (3-year OS, 9.1%).

CONCLUSIONS

The prognosis of M1c1 with localized peritoneal metastasis is relatively good, and can be further improved by surgical intervention. Combined evaluation of the M1c1/2 classification with the peritoneal metastasis grade may help in establishing more individualized treatment strategies.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer

The number of deaths from colorectal cancer in Japan continues to increase. Colorectal cancer deaths exceeded 50,000 in 2016. In the 2019 edition, revision of all aspects of treatments was performed, with corrections and additions made based on knowledge acquired since the 2016 version (drug therapy) and the 2014 version (other treatments). The Japanese Society for Cancer of the Colon and Rectum guidelines 2019 for the treatment of colorectal cancer (JSCCR guidelines 2019) have been prepared to show standard treatment strategies for colorectal cancer, to eliminate disparities among institutions in terms of treatment, to eliminate unnecessary treatment and insufficient treatment and to deepen mutual understanding between healthcare professionals and patients by making these guidelines available to the general public. These guidelines have been prepared by consensuses reached by the JSCCR Guideline Committee, based on a careful review of the evidence retrieved by literature searches and in view of the medical health insurance system and actual clinical practice settings in Japan. Therefore, these guidelines can be used as a tool for treating colorectal cancer in actual clinical practice settings. More specifically, they can be used as a guide to obtaining informed consent from patients and choosing the method of treatment for each patient. Controversial issues were selected as clinical questions, and recommendations were made. Each recommendation is accompanied by a classification of the evidence and a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSCCR guidelines 2019.

Prognostic predictions based on pathological findings of peritoneal dissemination in patients with stage IV colorectal cancer without residual disease (R0 status)

PURPOSE

This study aimed to clarify the prognosis of patients after resection of stage IV colorectal cancer and synchronous peritoneal metastasis (no residual disease: R0 status) based on histopathologic findings.

METHODS

The subjects of this study were 26 patients who underwent radical resection of synchronous peritoneal metastases of stage IV colorectal cancer. Only patients with one synchronous peritoneal metastasis were included in this study. The peritoneal lesions were initially classified into two categories based on the presence or absence of adenocarcinoma on their surface: RM-negative or RM-positive. The lesions were subsequently classified as being of massive or diffuse type and of small (< 6 mm) or large (≥ 6 mm) type according to the maximum metastatic tumor dimension.

RESULTS

Multivariate analysis revealed that massive type metastatic tumors were associated with a better disease-free survival (DFS; p = 0.047) and overall survival (OS; p = 0.033), than diffuse type tumors.

CONCLUSION

A detailed stratification of pathological findings could contribute remarkably to prognostic predictions for patients with synchronous peritoneal metastases.

Colorectal Peritoneal Metastases: A Systematic Review of Current and Emerging Trends in Clinical and Translational Research

Colorectal peritoneal metastases (CPM) are associated with abbreviated survival and significantly impaired quality of life. In patients with CPM, radical multimodality treatment consisting of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has demonstrated oncological superiority over systemic chemotherapy alone. In highly selected patients undergoing CRS + HIPEC, overall survival of over 60% has been reported in some series. These are patients in whom the disease burden is limited and where the diagnosis is made at an early stage in the disease course. Early diagnosis and a deeper understanding of the biological mechanisms that regulate CPM are critical to refining patient selection for radical treatment, personalising therapeutic approaches, enhancing prognostication, and ultimately improving long-term survivorship. In the present study, we outline three broad themes which represent critical future research targets in CPM: (1) enhanced radiological strategies for early detection and staging; (2) identification and validation of translational biomarkers for diagnostic, prognostic, and therapeutic deployment; and (3) development of optimized approaches for surgical cytoreduction as well as more precise strategies for intraperitoneal drug selection and delivery. Herein, we provide a contemporary narrative review of the state of the art in these three areas. A systematic review in accordance with PRISMA guidelines was undertaken on all English language studies published between 2007 and 2017. In vitro and animal model studies were deemed eligible for inclusion in the sections pertaining to biomarkers and therapeutic optimisation, as these areas of research currently remain in the early stages of development. Acquired data were then divided into hierarchical thematic categories (imaging modalities, translational biomarkers (diagnostic/prognostic/therapeutic), and delivery techniques) and subcategories. An interactive sunburst figure is provided for intuitive interrogation of the CPM research landscape.

Predictive factors of synchronous colorectal peritoneal metastases: Development of a nomogram and study of its utilities using decision curve analysis

BACKGROUND

The objective of this study was to summarize the clinicopathological and molecular features of synchronous colorectal peritoneal metastases (CPM). We then combined clinical and pathological variables associated with synchronous CPM into a nomogram and confirmed its utilities using decision curve analysis.

MATERIALS AND METHODS

Synchronous metastatic colorectal cancer (mCRC) patients who received primary tumor resection and underwent KRAS, NRAS, and BRAF gene mutation detection at our center from January 2014 to September 2015 were included in this retrospective study. An analysis was performed to investigate the clinicopathological and molecular features for independent risk factors of synchronous CPM and to subsequently develop a nomogram for synchronous CPM based on multivariate logistic regression. Model performance was quantified in terms of calibration and discrimination. We studied the utility of the nomogram using decision curve analysis.

RESULTS

In total, 226 patients were diagnosed with synchronous mCRC, of whom 50 patients (22.1%) presented with CPM. After uni- and multivariate analysis, a nomogram was built based on tumor site, histological type, age, and T4 status. The model had good discrimination with an area under the curve (AUC) at 0.777 (95% CI 0.703-0.850) and adequate calibration. By decision curve analysis, the model was shown to be relevant between thresholds of 0.10 and 0.66.

CONCLUSION

Synchronous CPM is more likely to happen to patients with age ≤60, right-sided primary lesions, signet ring cell cancer or T4 stage. This is the first nomogram to predict synchronous CPM. To ensure generalizability, this model needs to be externally validated.

LMR predicts outcome in patients after preoperative chemoradiotherapy for stage II-III rectal cancer

BACKGROUND

Recently, lymphocyte-to-monocyte ratio (LMR) has attracted attention as a new marker of the chronic systemic inflammatory response and has been associated with patient prognosis in those who underwent chemoradiotherapy (CRT) for several solid cancers. This study aimed to evaluate the association between LMR and the prognosis of patients with rectal cancer.

METHODS

A total of 183 stage II-III rectal cancer patients who underwent preoperative CRT followed by surgical R0 resection were retrospectively reviewed. The LMR was calculated from pre- and post-CRT blood samples. To determine the optimal cutoff value for pre- and post-CRT LMR for predicting relapse-free survival (RFS) and overall survival (OS), a receiver operator characteristic curve was used. Cox's proportional hazard models were applied to identify risk factors for recurrence and overall mortality.

RESULTS

Low LMR was observed in 54 patients (pre-CRT <4.0) and 29 patients (post-CRT <1.5). Although pre-CRT LMR correlated with tumor size and ypT stage, post-CRT LMR showed no correlation to any pathologic features. Median follow-up term was 66.3 months; the 5-year RFS and OS of all patients were 72.5% and 88.7%, respectively. We found that a low pre-CRT LMR was an independent risk factor for OS (hazard ratio, 2.83; 95% confidence interval 1.03-8.13; P = 0.043).

CONCLUSIONS

In rectal cancer patients who have undergone preoperative CRT, a low pre-CRT LMR is a poor prognostic factor for OS.

Long-Term Outcomes After R0 Resection of Synchronous Peritoneal Metastasis from Colorectal Cancer Without Cytoreductive Surgery or Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

The National Comprehensive Cancer Network (NCCN) guidelines for colon cancer recently added the following footnote regarding the therapeutic strategy for peritoneal metastases: "If R0 resection can be achieved, surgical resection of isolated peritoneal disease may be considered at experienced centers." This study investigated the efficacy of R0 resection of peritoneal metastasis from colorectal cancer without cytoreductive surgery or hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

This retrospective cohort study was conducted at a single-institution tertiary care cancer center. Among 496 consecutive M1c colorectal cancer patients, R0 resection was achieved for 94 patients (19%). The subjects were 78 consecutive patients with colorectal cancer and simultaneous peritoneal metastasis but no other distant metastases who underwent R0 resection at the National Cancer Center Hospital from 1971 to 2016 (16% of all M1c patients). Overall survival (OS) was investigated, and clinicopathologic variables were analyzed for prognostic significance.

RESULTS

No perioperative mortality was noted. The 3-year OS rate was 45%, and the 5-year OS rate was 28.7%. The median survival time was 33.4 months. Notably, 17 patients survived for more than 5 years, and 9 of these patients did not receive any chemotherapy. Multivariate analysis showed cancer location in the colon and harvesting of 12 or more lymph nodes to be independent factors associated with a better prognosis.

CONCLUSIONS

From the perspective of long-term outcomes and no perioperative mortality, R0 resection of peritoneal metastasis from colorectal cancer, without complete peritonectomy or HIPEC, appeared to be an acceptable therapeutic option for some patients with peritoneal metastasis.

Clinical Analysis of Primary Colorectal Signet-Ring Cell Carcinoma

The objective of the study was to investigate the clinicopathological features of primary colorectal signet-ring cell carcinoma. We retrospectively analyzed the clinical and survival data of 37 patients with primary colorectal signet-ring cell carcinoma. The mean survival time of patients in stage II, III, and IV were estimated using Student t test and the cumulative survival rates were estimated according to the method of Kaplan-Meier. The significance of the differences in survival rates were calculated using the log rank test. The incidence of primary colorectal signet-ring cell carcinoma was 1.40%, the median age of 37 patients was 50 years, the male to female ratio was 1.47:1, and 21 patients (56.8%) received a radical resection. Most patients 33 (89.2%) had an advanced tumor stage at the time of diagnosis (17 patients 45.9% stage III and 16 patients 43.2% stage IV), 34 (94.5%) patients showed a tumor depth of >T3, lymph node involvement occurred in 26 patients (70.3%), patients had a high incidence of peritoneal metastasis (16 patients 43.2% at presentation, 30 patients 81.1% at presentation and recurrence) and a low incidence of liver metastases (1 patients 2.7% at presentation, 5 patients 13.5% at presentation and recurrence). The 5-year survival rate after the initial surgery was 10.8%, the mean survival time of 37 patients was 27.1 ± 3.3 months, the mean survival time of patients in stage II, III, and IV were 47.0 ± 12.8 months, 37.1 ± 3.9 months, and 10.5 ± 1.4 months, respectively (P < .000). Colorectal signet-ring cell carcinoma is a rare neoplasm with a predominance in men. Its characteristic features were the advanced stage at the time of diagnosis, a high incidence of peritoneal metastases, a low incidence of liver metastasis, and a poor prognosis.

Aggressive resection of frequent peritoneal recurrences in colorectal cancer contributes to long-term survival

We report a long-term survivor of colorectal cancer who underwent aggressive, frequent resection for peritoneal recurrences. A 58-year-old woman was diagnosed with descending colon cancer. Resection of the descending colon along with lymph node dissection was performed in September 2006. The pathological findings revealed Stage IIA colorectal cancer. The following peritoneal recurrences were removed: two in July 2007, two in the omental fat and two in the pouch of Douglas in June 2008 resected by low anterior resection of the rectum, one in the uterus and right ovarian recurrence resected via bilateral adnexectomy and Hartmann’s procedure in May 2011, and one in the ascending colon by partial resection of the colon wall in December 2011. Postoperative adjuvant chemotherapy (uracil and tegafur/leucovorin, fluorouracil/levofolinate/oxaliplatin/bevacizumab, 5-fluorouracil/leucovorin/bevacizumab, irinotecan/bevacizumab, and irinotecan/panitumumab) was administered. The patient did not desire postoperative adjuvant chemotherapy after the fourth operation. The long-term survival was 6 years and 7 months.

Survival and Prognostic Factors for Metachronous Peritoneal Metastasis in Patients with Colon Cancer

BACKGROUND

The clinical course of metachronous peritoneal metastasis of colorectal origin is poorly understood. In this retrospective study, we aimed to elucidate survival and prognostic factors for metachronous peritoneal metastasis.

METHODS

Patients with metachronous peritoneal metastasis after curative resection for stage I-III colon cancer were retrospectively reviewed, and the incidence and prognosis of metachronous peritoneal metastasis were investigated. Prognostic factors were identified by univariate and multivariate analyses.

RESULTS

Among 1582 surgically resected stage I-III colon cancer patients, 65 developed metachronous peritoneal metastasis. The 5-year cumulative incidence rate was 4.5%, and the median survival after diagnosis of peritoneal metastasis was 29.6 months. None of the patients underwent peritonectomy or intraperitoneal chemotherapy. Independent prognostic factors included right colon cancer [hazard ratio (HR) 2.69, 95% confidence interval (CI) 1.26-5.64; p = 0.011], time to metachronous peritoneal metastasis of <1 year (HR 2.02, 95% CI 1.04-3.87; p = 0.040), Peritoneal Cancer Index (PCI) >10 (HR 3.68, 95% CI 1.37-8.99; p = 0.012), concurrent metastases (HR 4.09, 95% CI 2.02-8.23; p < 0.001), and peritoneal nodule resection (HR 0.31, 95% CI 0.13-0.65; p = 0.002).

CONCLUSIONS

A proportion of colon cancer patients with metachronous peritoneal metastasis may benefit from combined peritoneal nodule resection and systemic chemotherapy. Right colon cancer, early peritoneal metastasis, a high PCI, and concurrent metastases negatively affected prognosis in patients with metachronous peritoneal metastasis.

Palliative surgery for colorectal cancer with peritoneal metastasis: a propensity-score matching analysis

PURPOSE

Peritoneal metastasis (PM) in patients with colorectal cancer (CRC) is associated with poor prognosis. We conducted this study to assess whether palliative resection (PR) of the primary tumor improved the overall survival (OS) of patients with PM-CRC.

METHODS

We analyzed retrospectively, data collected prospectively from patients with CRC. PM was categorized into three subgroups according to the Japanese classification of PM. A propensity-score model was used to compare the outcomes of patients who underwent PR (PR group) and those who did not [non-resection (NR) group].

RESULTS

Among 1909 patients with metastatic CRC, 309 (16 %) had only peritoneal metastases and 255 of these patients who underwent palliative surgery (R2) were the subjects of our analysis: 161 in the PR group and 94 in the NR group. Median OS was significantly longer in the PR group than in the NR group (23 vs. 11 months, P < 0.001). Patients in the PR group had less extensive PM and a higher rate of receiving palliative chemotherapy than those in the NR group (P < 0.001). In a Cox multivariate analysis of 69 propensity-score matched pairs, PR resulted in significantly longer OS than NR (hazard ratio 0.496, 95 % confidence interval 0.268-0.919, P = 0.025).

CONCLUSIONS

Our results show that PR resulted in better OS than NR for patients with PM-CRC, when their overall condition permitted a more aggressive approach.

Characterization of cancer stem cells from different grades of human colorectal cancer

Colorectal cancer (CRC) is one of the most common solid tumors worldwide. Recent evidence suggests that a population of cancer cells, called cancer stem cells (CSCs), is responsible for tumor heterogeneity, invasion, metastasis, therapeutic resistance, and recurrence of CRC. The isolation and characterization of CSCs using cell surface markers have been reported previously with varying results. In this study, we investigated a panel of four putative CSC markers, CD44, CD24, CD166, and EpCAM, to define CRC-CSC. Paraffin embedded tissue samples from different grades of primary, untreated CRC were analyzed for the expression of four CSC markers CD44, CD326, CD24, and CD166, using immunohistochemistry. Flow cytometric analysis of CRC-CSC from HT29 (low grade) and HCT116 (high grade) human colorectal cancer cell lines was done. Marker-based isolation of CSC and non-CSC-bulk-tumor cells from HT29 was done using FACS, and tumor sphere assay was performed. There was a statistically significant difference (p < 0.05) in the expression of CD44, CD326, and CD166 between cases and controls. A novel cutoff distribution of CD44 and CD166 was suggested to help for better immunohistochemical analysis of CRC. Higher prevalence of CSC was seen in high-grade CRC as compared to low-grade CRC. Sorted and cultured CD44 + CD166+ cells formed tumor spheres, suggesting that these cells, having properties of self renewal and anchorage independent proliferation, were in fact CSC. Hence, CD44 and CD166 may serve as good CRC-CSC markers when used together with novel cutoff immunohistochemistry (IHC) expression levels.

Prognostic impact of carcinoembryonic antigen and carbohydrate antigen 19-9 in stage IV colorectal cancer patients after R0 resection

BACKGROUND

Although preoperative carcinoembryonic antigen (pre-CEA) and carbohydrate antigen 19-9 (pre-CA 19-9) are reportedly prognostic indicators for colorectal cancer (CRC), the prognostic roles of postoperative CEA (post-CEA) and CA 19-9 (post-CA 19-9) shortly after surgery have not been clarified in patients with curatively resected stage IV CRC. The aim of this study was to evaluate the predictive abilities of post-CEA and post-CA 19-9.

METHODS

A total of 129 consecutive patients who had stage IV CRC and underwent R0 resection were retrospectively analyzed. Pre-CEA and post-CEA and CA 19-9 levels were measured within 1 mo before and 3 mo after surgery, respectively. Relapse-free survival (RFS) and overall survival were estimated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox proportional hazards model.

RESULTS

Pre-CEA was elevated (≥5.0 ng/mL) in 73.6% of the patients and remained elevated after surgery in 32.7% of the patients. Elevated post-CA 19-9 (≥50 U/mL) was observed in 9.5% of the patients. Neither elevated pre-CEA nor elevated pre-CA 19-9 was significantly associated with RFS but both elevated post-CEA and elevated post-CA 19-9 were associated with markedly reduced RFS (P = 0.0002 and P = 0.0004, respectively). When considered in combination, post-CEA and post-CA 19-9 significantly stratified RFS and was an independent predictive factor for recurrence (P = 0.0035), as was lymphatic invasion (P = 0.0015). Post-CA 19-9 was the only evident independent predictive factor for overall survival (P = 0.0336).

CONCLUSIONS

In patients with stage IV CRC who underwent curative resection, the combination of post-CEA and post-CA 19-9 at 3 mo after surgery was a potent prognostic indicator for recurrence.

Factors affecting recurrence and prognosis after R0 resection for colorectal cancer with peritoneal metastasis

BACKGROUND

Peritoneal metastases (PM) are a well-known poor prognostic factor. The aim of this study was to investigate the factors affecting recurrence and prognosis after R0 resection for colorectal cancer with synchronous peritoneal metastases.

METHODS

We conducted a multi-institutional retrospective analysis of 72 patients without distant metastases who underwent R0 surgery between 1991 and 2007 for colorectal cancer with PM localized to the adjacent peritoneum. Clinicopathological variables were analyzed for their significance to recurrence and prognosis.

RESULTS

Recurrence was found in 51 patients (70.8%) after R0 surgery. In logistic regression analyses, lymph node metastasis was shown to be an independent factor affecting recurrence. Non-intensive or no postoperative chemotherapy and eight or fewer dissected lymph nodes were identified as independent poor prognostic factors using the Cox proportional hazards model. Among patients who received postoperative chemotherapy, prognosis was significantly better in those who received intensive adjuvant chemotherapy using camptothecin-11 or oxaliplatin after R0 surgery than in those who received non-intensive chemotherapy. Among 47 patients whose recurrence date was known, 33 patients (70.2%) experienced recurrence within 18 months after R0 surgery for peritoneal metastases, and hematogenous recurrence was observed significantly more often than peritoneal recurrence.

CONCLUSIONS

Harvesting of more than eight lymph nodes and administration of intense adjuvant chemotherapy after R0 surgery are recommended for greater prediction accuracy and improved prognosis. Intensive follow-up should be performed within 18 months after R0 surgery for colorectal cancer with synchronous peritoneal metastases.

Prognoses and treatment strategies for synchronous peritoneal dissemination of colorectal carcinoma

PURPOSE

We devised a simple dichotomous classification system and showed sufficient reproducibility to indicate treatment strategies for peritoneal metastasis of colorectal cancer.

METHODS

We included 67 patients with peritoneal metastasis of colorectal cancer and classified them according to the largest lesion size, number of lesions and number of regional peritoneal metastases. The oncological data were recorded and compared.

RESULTS

According to the univariate analyses, the prognoses were significantly better in patients with ≤3 disseminated lesions than in those with ≥4, and in patients with disseminated lesions in only one region than in those with ≥2 lesions. A multivariate analysis showed that primary tumor resection and the presence of peritoneal metastases in only one region were favorable factors for the patient survival. Patients with disseminated lesions in only one region (localized group) and those with nonlocalized lesions had three-year survival rates of 45.6 and 12.2 %, respectively. Finally, primary tumor resection improved the prognoses in both the localized and nonlocalized groups.

CONCLUSIONS

Colorectal cancer patients were categorized into localized and nonlocalized groups according to the number of regions with peritoneal metastasis, and significant prognostic associations were demonstrated. Subsequent analyses of the oncological data suggested that primary tumor resection contributes to an improved prognosis in all patients with synchronous peritoneal metastases.

Evaluation of the efficacy of peritoneal lavage with distilled water in colorectal cancer surgery: in vitro and in vivo study

BACKGROUND

Peritoneal lavage with distilled water has been performed during colorectal cancer surgery. This study investigated the cytocidal effects of hypotonic shock in vitro and in vivo in colorectal cancer cells.

METHODS

Three human colorectal cancer cell lines, DLD1, HT29, and CACO2, were exposed to distilled water, and morphological changes were observed under a differential interference contrast microscope connected to a high-speed digital video camera. Cell volume changes were assessed using a high-resolution flow cytometer. Re-incubation experiments were performed to investigate the cytocidal effects of distilled water. In the in vivo experiment, cancer cells after hypotonic shock were injected intraperitoneally into mice and the degree of established peritoneal metastasis was subsequently evaluated. The effects of the blockade of Cl(-) channels on these cells during hypotonic shock were also analyzed.

RESULTS

Morphological observations revealed a rapid cell swelling followed by cell rupture. Measurements of cell volume changes showed that mild hypotonic shock induced regulatory volume decrease (RVD) while severe hypotonic shock broke cells into fragments. Re-incubation experiments demonstrated the cytocidal effects of hypotonicity. In vivo experiments revealed the absence of peritoneal dissemination in mice in the distilled water group, and its presence in all mice in the control group. The blockade of Cl(-) channels increased cell volume by inhibiting RVD and enhanced cytocidal effects during mild hypotonic shock.

CONCLUSIONS

These results clearly support the efficacy of peritoneal lavage with distilled water during colorectal cancer surgery and suggest that regulating of Cl(-) transport may enhance the cytocidal effects of hypotonic shock.