Prognostic Impact of R0 Resection and Targeted Therapy for Colorectal Cancer with Synchronous Peritoneal Metastasis

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.

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy versus R0 resection for resectable colorectal cancer with peritoneal metastases and low peritoneal cancer index scores: a collaborative observational study from Korea and Japan

BACKGROUND

The benefits of hyperthermic intraperitoneal chemotherapy (HIPEC) after cytoreductive surgery (CRS) for colorectal cancer with peritoneal metastasis (CPM) remain controversial. R0 resection without peritoneal stripping might be as effective as CRS plus HIPEC. The authors aimed to compare the long-term oncological outcomes of patients with CPM and peritoneal cancer index (PCI) scores less than or equal to 6 who underwent R0 resection in Japan with those who underwent CRS plus HIPEC in Korea.

MATERIALS AND METHODS

This international, retrospective cohort study was conducted in Korea and Japan using a prospectively collected clinical database. Patients who underwent surgery from July 2014 to December 2021 for CPM with a PCI score of less than or equal to 6 and completeness of the cytoreduction score-0 were included. The primary outcome was relapse-free survival (RFS), and the secondary outcomes were overall survival, peritoneal RFS (PRFS), and postoperative outcomes.

RESULTS

The 3-year RFS was significantly longer in the CRS+HIPEC group than in the R0 resection group: 35.9% versus 6.9% ( P <0.001); 31.0% versus 6.7% ( P =0.040) after propensity score matching. The median PRFS was significantly longer in the CRS+HIPEC group than in the R0 resection group: 24.5 months versus 17.2 months ( P =0.017). The 3-year overall survival and postoperative complications did not significantly differ between the two groups.

CONCLUSIONS

RFS and PRFS rates were significantly prolonged after CRS plus HIPEC, whereas postoperative complications and length of hospital stay were not increased. Therefore, curative CRS plus HIPEC may be considered a treatment strategy for selected patients with resectable CPM and low PCI scores.

Peritoneal Metastasis: A Dilemma and Challenge in the Treatment of Metastatic Colorectal Cancer

Peritoneal metastasis (PM) is a common mode of distant metastasis in colorectal cancer (CRC) and has a poorer prognosis compared to other metastatic sites. The formation of PM foci depends on the synergistic effect of multiple molecules and the modulation of various components of the tumor microenvironment. The current treatment of CRC-PM is based on systemic chemotherapy. However, recent developments in local therapeutic modalities, such as cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC), have improved the survival of these patients. This article reviews the research progress on the mechanism, characteristics, diagnosis, and treatment strategies of CRC-PM, and discusses the current challenges, so as to deepen the understanding of CRC-PM among clinicians.

Hyperthermic intraperitoneal chemotherapy following up-front cytoreductive surgery versus cytoreductive surgery alone for isolated synchronous colorectal peritoneal metastases: A retrospective, observational study

Background

To date, the value of hyperthermic intraperitoneal chemotherapy (HIPEC) following up-front resection for isolated synchronous colorectal peritoneal metastases seems controversial.

Patients and Methods

This retrospective cohort study was conducted from September 1, 2012, to September 1, 2019, at a tertiary medical center in China. Patients with isolated synchronous colorectal peritoneal metastases were included in CRS plus HIPEC group or CRS alone group based on the treatment history. Overall survival and relapse-free survival were estimated using Cox proportional hazards regression analysis and Kaplan–Meier method.

Results

78 patients with isolated synchronous colorectal peritoneal metastases were identified among 396 patients with synchronous colorectal peritoneal metastases. 43 were in the cytoreductive surgery plus HIPEC group and 35 were in the cytoreductive surgery alone group. Among them, 61 patients had relapse-free survival data. The median peritoneal cancer index was 4 in all patients. After a median follow-up of 46.0 months, 5-year overall survival was 66.8% and the median relapse-free survival was 36.0 (95% CI, 6.8-65.1) months in the CRS plus HIPEC group. 5-year overall survival was 31.2% and the median relapse-free survival was 12.0 (95% CI, 9.0-15.0) months in the CRS alone group. Cox regression analyses showed that HIPEC was the independent prognostic factor for overall survival (P = 0.004) and relapse-free survival (P = 0.049).

Conclusion

Findings of the present study suggest that HIPEC following up-front CRS could improve overall survival and relapse-free survival in patients with isolated synchronous colorectal peritoneal metastases.

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.

Lymphocyte-to-C-Reactive Protein Ratio Is the Most Sensitive Inflammation-Based Prognostic Score in Patients With Unresectable Metastatic Colorectal Cancer

BACKGROUND

Systemic inflammation contributes to the progression of malignancies. The preoperative lymphocyte-to-C-reactive protein ratio has recently been shown to predict survival of patients with colorectal cancer who undergo surgery, but its prognostic value remains unclear in patients with unresectable metastatic colorectal cancer.

OBJECTIVE

This study aimed to examine the prognostic values of inflammation-based prognostic scores in patients with metastatic colorectal cancer, focusing on the lymphocyte-to-C-reactive protein ratio.

DESIGN

This is a retrospective study from a prospectively collected database.

SETTINGS

This study was conducted at a high-volume multidisciplinary tertiary cancer center in Japan.

PATIENTS

The subjects were 756 consecutive patients with unresectable metastatic colorectal cancer who received systemic chemotherapy from 2000 to 2015. The prognostic value of the lymphocyte-to-C-reactive protein ratio was evaluated by univariable and multivariable analyses. Time-dependent receiver operating characteristics curve analysis was conducted to compare the prognostic impact of the lymphocyte-to-C-reactive protein ratio with the impact of the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, or the modified Glasgow Prognostic Score.

MAIN OUTCOME MEASURES

The primary outcomes measured were the correlations of prognostic scores with overall survival.

RESULTS

Median survival times of patients with high, intermediate, and low lymphocyte-to-C-reactive protein ratios were 29.4, 19.3, and 13.1 months (p < 0.001). In all subgroups according to key prognostic factors (performance status, use of targeted agents, pretreatment CEA levels, tumor sidedness, M category, and primary tumor resection), patient prognosis could be clearly stratified into 3 groups by the lymphocyte-to-C-reactive protein ratio. Multivariable analysis revealed that decreased lymphocyte-to-C-reactive protein ratio was independently associated with reduced survival (low vs high: HR 1.96, p < 0.001; intermediate vs high: HR 1.44, p < 0.001). The time-dependent receiver operating characteristics curve analysis revealed that the lymphocyte-to-C-reactive protein ratio was the most sensitive predictor of survival among all inflammation-based prognostic scores on a continuous basis.

LIMITATIONS

This study was retrospective in nature.

CONCLUSIONS

The lymphocyte-to-C-reactive protein ratio is a useful prognostic biomarker for unresectable metastatic colorectal cancer and could contribute to accurate prognostication and therapeutic decision making. See Video Abstract at http://links.lww.com/DCR/B600.

RELACIN ENTRE LINFOCITOS Y PROTENA C ES EL SCORE PRONOSTICO INFLAMATORIO MAS SENSIBLE EN PACIENTES CON CNCER COLORRECTAL METASTSICO IRRESECABLE

ANTECEDENTES:La inflamación sistémica contribuye en la progresión de neoplasias malignas. Recientemente se ha demostrado que la proporción preoperatoria de linfocitos -proteína C reactiva predice la supervivencia de los pacientes con cáncer colorrectal que se sometieron a cirugía, pero su valor pronóstico sigue sin estar claro en pacientes con cáncer colorrectal metastásico irresecable.OBJETIVO:Evaluar el valor pronostico de los scores inflamtorios centrandose en linfocito- proteina c reactiva en pacientes con cáncer colorrectal metastásico.DISEÑO:Estudio retrospective evaluando una base de datos.AJUSTE:Este estudio se llevó a cabo en un centro oncológico terciario multidisciplinario de gran volumen en Japón.PACIENTES:Se incluyeron 756 pacientes consecutivos todos con cáncer colorrectal metastásico irresecable que recibieron quimioterapia sistémica de 2000 a 2015. El valor pronóstico de la proteína C reactiva se evaluó mediante análisis univariables y multivariables. Se realizó análisis de la curva de características operativas del receptor dependiente del tiempo para comparar el impacto pronóstico de la proteína linfocito-C-reactiva con el de la proporción de neutrófilos a linfocitos, la proporción de plaquetas a linfocitos, la proporción de linfocitos a monocitos o la proporción de puntuación pronóstica segun escala de Glasgow modificada.PRINCIPALES MEDIDAS DE RESULTADO:Correlacion de las puntuaciones pronósticas con la supervivencia global.RESULTADOS:La mediana de supervivencia de los pacientes con niveles altos, intermedios y bajos de proteína C reactiva de linfocitos fue de 29,4, 19,3 y 13,1 meses, respectivamente (p <0,001). En todos los subgrupos de acuerdo con los factores pronósticos clave (estado funcional, uso de agentes dirigidos, niveles de antígeno carcinoembrionario antes del tratamiento, lado del tumor, categoría M y resección del tumor primario), el pronóstico del paciente podría estratificarse claramente en tres grupos por linfocito a C- proteína reactiva. El análisis multivariable reveló que la disminución de linfocitos a proteína C reactiva se asoció de forma independiente con una supervivencia reducida (baja frente a alta: cociente de riesgo 1,96, p <0,001; intermedio frente a alto: cociente de riesgo 1,44, p <0,001). El análisis de la curva de características operativas del receptor dependiente del tiempo reveló que de linfocito a proteína C reactiva era el predictor de supervivencia más sensible entre todas las puntuaciones de pronóstico basadas en inflamación de forma continua.LIMITACIONES:Este estudio fue de naturaleza retrospectiva.CONCLUSIONES:La proteína C reactiva de linfocitos a C es un biomarcador pronóstico útil para el cáncer colorrectal metastásico irresecable y podría contribuir a un pronóstico preciso y a la toma de decisiones terapéuticas. Consulte Video Resumen en http://links.lww.com/DCR/B600.

Comparison of model fit and discriminatory ability of M category as defined by the 7th and 8th editions of the tumor-node-metastasis classification of colorectal cancer and the 9th edition of the Japanese classification

Background

In transitioning from the 7th edition of the tumor‐node‐metastasis classification (TNM‐7) to the 8th edition (TNM‐8), colorectal cancer with peritoneal metastasis was newly categorized as M1c. In the 9th edition of the Japanese Classification of colorectal, appendiceal, and anal carcinoma (JPC‐9), M1c is further subdivided into M1c1 (without other organ involvement) and M1c2 (with other organ involvement). This study aimed to compare the model fit and discriminatory ability of the M category of these three classification systems, as no study to date has made this comparison.

Methods

The study population consisted of stage IV colorectal cancer patients who were referred to the National Cancer Center Hospital from 2000 to 2017. The Akaike information criterion (AIC), Harrell's concordance index (C‐index), and time‐dependent receiver operating characteristic (ROC) curves were used to compare the three classification systems. Subgroup analyses, stratified by initial treatment year, were also performed.

Results

According to TNM‐8, 670 (55%) patients had M1a, 273 (22%) had M1b, and 279 (23%) had M1c (87 M1c1 and 192 M1c2 using JPC‐9) tumors. Among the three classification systems, JPC‐9 had the lowest AIC value (JPC‐9: 10546.3; TNM‐7: 10555.9; TNM‐8: 10585.5), highest C‐index (JPC‐9: 0.608; TNM‐7: 0.598; TNM‐8: 0.599), and superior time‐dependent ROC curves throughout the observation period. Subgroup analyses were consistent with these results.

Conclusions

While the revised M category definition did not improve model fit and discriminatory ability from TNM‐7 to TNM‐8, further subdivision of M1c in JPC‐9 improved these parameters. These results support further revisions to M1 subcategories in future editions of the TNM classification system.

Thirty-three long-term survivors after cytoreductive surgery in patients with peritoneal metastases from colorectal cancer: a retrospective descriptive study

BACKGROUND

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival in selected patients with peritoneal metastasis (PM) from colorectal cancer (CRC). However, little has been reported on characteristics and clinical course of long-term survivors with CRC-PM beyond 5 years. The objective of this study was to identify the clinical and oncological features affecting long-term survival of CRC-PM after comprehensive treatment.

METHODS

Between January 1990 and April 2015, CRC-PM patients who underwent CRS with or without HIPEC in two Japanese tertiary hospitals were analyzed. Clinicopathological parameters and therapeutic details for long-term survivors (patients surviving ≥ 5 years after CRS) were described and compared with those for non-survivors (patients surviving < 5 years).

RESULTS

The study identified 236 patients with CRC-PM who underwent CRS, with a median follow-up period of 2.5 years. Thirty-three patients (14.0%) were considered as long-term survivors. Compared with non-survivors, long-term survivors had a lower median peritoneal cancer index (PCI) [4 (1-27) vs 9 (0-39), p < 0.001]. Complete cytoreduction (CCR-0) was achieved in all long-term survivors, with a significantly higher rate [33/33 (100%) vs 141/203 (69.8%), p < 0.001]. Metachronous onsets of PM were more frequently observed in the long-term survivor group [26/33 (78.8%) vs 103/203 (50.3%), p = 0.018]. Regarding histopathology, long-term survivors more frequently had mucinous adenocarcinoma than non-survivors [8/33 (24.2%) vs 27/203 (13.3%)] and less likely exhibited poorly differentiated or signet ring cell carcinoma [2/33 (6.1%) vs 48/203 (23.7%)] (p < 0.001).

CONCLUSIONS

One in seven patients with CRC-PM achieved the long-term milestone after CRS. A long-term survival was associated with the presence of low PCI, CCR-0, metachronous onset, and mucinous histology.

Exosomal miR-193a and let-7g accelerate cancer progression on primary colorectal cancer and paired peritoneal metastatic cancer

A metastasis of colorectal cancer is difficult to diagnose, and has a poor prognosis. Therefore, we tried to elucidate the possibility of a diagnostic and prognostic marker. Exosomal miR-193a and let-7g were sorted by miRNA microarray. The expression of miR-193a in the PTM group was lower than that of the primary CRC group, and the expression of let-7g was higher than that of the primary CRC. MMP16 and CDKN1A expression was confirmed respectively for target genes of two miRNAs. When the mimics of these miRNAs were treated with cell lines, both MMP16 and CDKN1A decreased intracellular expression. Cell invasiveness and proliferation were decreased by miR-193a and increased by let-7g. The differences in expression of exosomal miR-193a and let-7g extracted from the plasma of patients were classified as cancer progression indicators. Furthermore, the survival rate decreased in the group with low miR-193a expression and high let-7g expression. Our study confirmed the possibility of using this as a diagnostic and prognostic marker for colorectal cancer by measuring the expression levels of exosomal miR-193a and let-7g in blood.

Nutritional and inflammatory measures predict survival of patients with stage IV colorectal cancer

Background

This study aimed to evaluate the prognostic impact of nutritional and inflammatory measures (controlling nutritional status (CONUT) score, prognostic nutritional index (PNI), and modified Glasgow prognostic score (mGPS)) on overall survival (OS) in patients with stage IV colorectal cancer (CRC).

Methods

Subjects were 996 patients with stage IV CRC who were referred to the National Cancer Center Hospital between 2001 and 2015. We retrospectively investigated correlations between OS and CONUT score, PNI, and mGPS. Multivariate analyses were performed using Cox proportional hazards regression models.

Results

After adjusting for known factors (age, gender, BMI, ECOG performance status, location of primary tumor, CEA levels, histological type, M category, and prior surgical treatment), all three measures were found to be independent prognostic factors for OS in patients with stage (CONUT score, p < 0.001; PNI, p < 0.001; mGPS, p < 0.001). Significant differences in OS were found between low CONUT score (0/1) (n = 614; 61%) and intermediate CONUT score (2/3) (n = 276; 28%) (hazard ratio (HR) = 1.20, 95% confidence interval (CI): 1.02–1.42, p = 0.032), and intermediate CONUT score and high CONUT score (≥4) (n = 106; 11%) (HR = 1.30, 95% CI: 1.01–1.67, p = 0.045). Significant differences in OS were found between mGPS = 0 (n = 633; 64%) and mGPS = 1 (n = 234; 23%) (HR = 1.84, 95% CI: 1.54–2.19, p < 0.001), but not between mGPS = 1 and mGPS = 2 (n = 129; 13%) (HR = 1.12, 95% CI: 0.88–1.41, p = 0.349). Patients with low PNI (< 48.0) (n = 443; 44%) showed a significantly lower OS rate than those with high PNI (≥48.0) (n = 553; 56%) (HR = 1.39, 95% CI: 1.19–1.62, p < 0.001).

Conclusions

CONUT score, PNI, and mGPS were found to be independent prognostic factors for OS in patients with stage IV CRC, suggesting that nutritional and inflammatory status is a useful host-related prognostic indicator in stage IV CRC.

Impact of Surgical Resection on Metachronous Metastases of Colorectal Cancer According to Tumor Doubling Time

BACKGROUND/AIM

We aimed to elucidate the prognostic impact of tumor doubling time (DT) and radical surgery when classified by DT in patients with metachronous liver, lung, or peritoneal metastases of colorectal cancer (CRC).

PATIENTS AND METHODS

We reviewed the data of 1941 patients who underwent curative surgery for CRC and calculated DT for recurrences using computed tomography.

RESULTS

Short DT was an independent prognostic risk factor in liver (p<0.001) and peritoneal (p=0.03) metastases. Survival was significantly better in patients who underwent surgery than in those who did not, both in short and long DT groups in any metastatic organ (p<0.01). Patients with long DT gained significantly better prognostic benefit from surgery than those with short DT in liver (p=0.01) and peritoneal (p=0.04) metastases.

CONCLUSION

Surgery is recommended for resectable metastases, especially in patients with liver and peritoneal metastases with long DT.

Prognostic impact of primary tumor location in Stage III colorectal cancer-right-sided colon versus left-sided colon versus rectum: a nationwide multicenter retrospective study

BACKGROUND

Previous studies investigating the impact of tumor location on colorectal cancer prognosis only compared two groups by location, e.g., 'right-sided colon vs. left-sided colon,' 'colon vs. rectum,' and 'right-sided (right-sided colon) vs. left-sided (left-sided colon and rectum).' This nationwide multicenter retrospective study aimed to clarify the prognostic impact of tumor location in patients with stage III colorectal cancer by classifying tumors into three groups: right-sided colon, left-sided colon, and rectum.

METHODS

Subjects were 9194 patients with stage III colorectal cancer who underwent curative surgery from 1997 to 2012. Relapse-free survival (RFS) after primary surgery and overall survival (OS) after recurrence were examined.

RESULTS

Rectal cancer (n = 2922) was associated with worse RFS compared to right-sided colon cancer (n = 2362) (hazard ratio (HR) 0.65; 95% CI 0.59-0.72; p < 0.001) and left-sided colon cancer (n = 3910) (HR 0.72; 95% CI 0.66-0.78; p < 0.001) after adjusting for key clinical factors (i.e., sex, age, histological type, CEA, adjuvant therapy, T category, and N category). Among patients with recurrence (n = 2823), rectal cancer was associated with better OS compared to right-sided colon cancer (HR 1.23; 95% CI 1.08-1.40; p = 0.002) and worse OS compared to left-sided colon cancer (HR 0.88; 95% CI 0.79-0.99; p = 0.029). Twenty percent of right-sided colon cancer recurrences exhibited peritoneal dissemination, 42% of left-sided colon cancer recurrences were liver metastases, and 33% of rectal cancer recurrences were local recurrences.

CONCLUSIONS

The three tumor locations (right-sided colon, left-sided colon, rectum) had different prognostic implications for recurrence after curative resection and overall mortality, suggesting that tumor location serves as a prognostic biomarker in stage III colorectal cancer.

Diagnostic and therapeutic algorithm for colorectal peritoneal metastases. A consensus of the peritoneal surface malignancies onco-team of the Italian society of surgical oncology

AIM

the surgical workup for colorectal cancer peritoneal metastases (CRCPM) is complex and should be managed in specialized centers. Diagnostic and therapeutic algorithms (DTA) have been proposed to balance optimal patients management and correct use of resources. Aim of this study was to establish a consensus on DTA for CRCPM patients in Italy.

METHOD

a panel of 18 delegated members of centers afferent to Peritoneal Surface Malignancies Onco-team of the Italian Society of Surgical Oncology was established. A list of statements regarding the DTA of patients with CRCPM was prepared according to different activities and decision-making nodes with a defined entry and exit point. Consensus was obtained through RAND UCLA methodology.

RESULTS

two different DTA were defined and approved according to the modality of presentation of CRCPM (synchronous and metachronous). A consensus was also obtained on 17 of the 19 statements related to DTA.

CONCLUSION

a shared model of DTA is now available for healthcare providers to monitor appropriateness in diagnosis and treatment of patients with isolated peritoneal metastases from CRC.

Less intensive surveillance after radical surgery for stage I-III colorectal cancer by focusing on the doubling time of recurrence

PURPOSE

To propose a new and improved surveillance schedule for colorectal cancer (CRC) patients by focusing on the recurrence rate, resectability, and especially, the tumor doubling time (DT) of recurrent tumors.

METHODS

The subjects of this retrospective review were 1774 consecutive patients who underwent radical surgery for stage I-III CRC between January, 2004 and December, 2015. We calculated the DT by measuring the tumor diameter using computed tomography (CT).

RESULTS

The median DT for recurrences in the liver, lung, peritoneum, and other locations were 35, 72, 85, and 36 days, respectively, (p < 0.001) and tumor growth rates differed according to the organs where recurrence developed. Multiple linear regression analysis showed that the DT was strongly associated with the relapse-free interval from primary surgery (p < 0.001), and that the DT in patients with recurrence detected ≥ 3 years after primary surgery was longer by 151.1 days than that in patients with recurrence detected within 1 year after primary surgery. We proposed a less intensive surveillance, which achieved an average cost reduction of 32.5% compared with conventional surveillance in Japan.

CONCLUSION

We propose a new and more cost-efficient surveillance schedule for CRC surgery patients in the clinical setting.

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.

Bevacizumab improves survival in metastatic colorectal cancer patients with primary tumor resection: A meta-analysis

It is not well determined whether primary tumor resection is associated with better outcomes in metastatic colorectal cancer (mCRC) patients treated with bevacizumab. In this meta-analysis, we aimed to assess the prognostic role of primary tumor resection in mCRC treated with bevacizumab. Electronic databases including the Cochrane library, Embase, and Pubmed were searched until April 2018. Clinical studies assessing the influence of primary tumor resection on the efficacy of bevacizumab in patients with mCRC were identified. The primary endpoint was overall survival (OS), and the secondary endpoint was progression-free survival (PFS). Seven studies including 2760 mCRC patients were finally included. The results of the meta-analysis were in favor of bevacizumab to patients with resected primary tumor in terms of OS (HR = 0.50, 95%CI: 0.39–0.64; p < 0.01), and PFS (HR = 0.65, 95%CI: 0.51–0.81; p < 0.01). Administration of bevacizumab in mCRC patients with resected primary tumor had a better OS (HR = 0.65, 95%CI: 0.56–0.74; p < 0.01), when compared to chemotherapy(CT). Adding bevacizumab to mCRC patients without resection of primary tumor also had a better OS (HR = 0.78, 95%CI: 0.65–0.94; p < 0.01) and PFS (HR = 0.71, 95%CI: 0.57–0.88; p < 0.01) compared to chemotherapy alone. In conclusion, mCRC patients with resected primary tumor have better survival than those without surgery of primary tumor when treated with bevacizumab. Primary tumor resection status should be taken into consideration when using bevacizumab in mCRC.

Factors affecting R0 resection of colorectal cancer with synchronous peritoneal metastases: a multicenter prospective observational study by the Japanese Society for Cancer of the Colon and Rectum

BACKGROUND

In Japan, R0 resection has been recommended for colorectal cancer patients with peritoneal metastases confined to the adjacent peritoneum and those with a few metastases to the distant peritoneum. R0 resection for M1c disease has drawn attention in Western countries and is currently considered an acceptable therapeutic option in the US National Comprehensive Cancer Network guidelines. However, clinical factors that affect the choice of R0 resection are unknown.

METHODS

This multicenter, prospective, observational study was conducted by the Japanese Society for Cancer of the Colon and Rectum. Colorectal cancer patients with synchronous peritoneal metastases were enrolled at 28 institutions in Japan from October 2012 to December 2016. To determine factors affecting R0 resection and R1 resection with intended R0 resection, stepwise logistic regression analyses were performed on clinical factors including age, sex, performance status (PS), body mass index, peritoneal cancer index (PCI) score, presence of ascites, presence of distant metastases, and primary tumor site.

RESULTS

R0/R1 resection was performed in 36 (31/5; 25%) of 146 patients. No distant metastases [odds ratio (OR) 52.9; 95% confidence interval (CI) 13.3-210.1; p < 0.0001], low PCI score (1-6) (OR 20.0; 95% CI 4.8-83.4; p < 0.0001), and high PS (0) (OR 2.40; 95% CI 0.66-8.68; p = 0.18) were independent factors affecting R0/R1 resection. PCI score and PS were also independent factors affecting R0/R1 resection in M1c patients without non-peritoneal distant metastases (n = 59).

CONCLUSION

Distant metastases, PCI score, and PS are three factors which affect R0 resection for M1c disease.

Primary Tumor Resection for Stage IV Colorectal Cancer in the Era of Targeted Chemotherapy

BACKGROUND

In the current era of targeted therapies, the benefits of resection of primary tumors in patients with unresectable stage IV colorectal cancer, specifically with regard to overall survival, are unknown.

METHODS

Our study population comprised 208 consecutive patients with unresectable stage IV colorectal cancer who received chemotherapy containing at least one molecular target agent, bevacizumab, cetuximab, and panitumumab, at the National Cancer Center Hospital from 2006 to 2013. To lessen the effects of confounding factors between two treatment groups (resection versus non-resection) such as performance status, presence of severe symptoms, M subcategories (M1a versus M1b, M1c) according to the TNM classification, primary tumor site, and CEA value, we conducted three different propensity score analyses (regression adjustment, stratification, and matching).

RESULTS

Of the 208 patients, 108 (52%) underwent resection of the primary tumor, while 100 (48%) did not. Regression adjustment revealed that resection was not associated with longer overall survival (hazard ratio of 0.70 (95% CI [0.49-1.00]; p = 0.051)). Stratification analysis of five strata revealed inconsistent results (hazard ratios ranged from 0.50 to 1.58); specifically, resection was associated with longer overall survival in four strata, but with shorter survival in one stratum. The propensity score-matched cohort (64 matched pairs) yielded a hazard ratio of 0.76 (95% CI [0.51-1.15]; p = 0.197).

CONCLUSIONS

All three analyses revealed that, in the current era of chemotherapy with target agents, primary tumor resection was only marginally influential and did not significantly improve overall survival over chemotherapy alone.

Prognostic factors of brain metastases from colorectal cancer

Background

For brain metastases from non-specific primary tumors, the most frequently used and validated clinical prognostic assessment tool is Karnofsky performance status (KPS). Given the lack of prognostic factors of brain metastases from colorectal cancer (CRC) other than KPS, this study aimed to identify new prognostic factors.

Methods

This retrospective cohort study was conducted at a tertiary care cancer center. Subjects were patients with brain metastases from CRC among all patients who received initial treatment for CRC at the National Cancer Center Hospital from 1997 to 2015 (n = 7147). Prognostic clinicopathological variables for overall survival (OS) were investigated.

Results

There were 68 consecutive patients with brain metastases from CRC, corresponding to 1.0% of all patients with CRC during the study period. Median survival time was 6.8 months. One-year and 3-year OS rates were 28.0 and 10.1%, respectively. Among the six covariates tested (age, KPS, presence of extracranial metastases, control of primary lesion, number of brain metastases, and history of chemotherapy), multivariate analysis revealed KPS (score ≥ 70), number of brain metastases (1–3), and no history of chemotherapy to be independent factors associated with better prognosis.

Conclusions

In addition to KPS, the number of brain lesions and history of chemotherapy were independent prognostic factors for OS in patients with brain metastases from CRC. An awareness of these factors may help gastrointestinal surgeons make appropriate choices in the treatment of these patients.

Long-term outcomes after surgical dissection of inguinal lymph node metastasis from rectal or anal canal adenocarcinoma

Background

The 8th edition of the tumor-node-metastasis (TNM) classification classifies inguinal lymph nodes as regional lymph nodes for anal canal carcinoma but non-regional lymph nodes for rectal carcinoma. This difference might reflect the different prognosis of inguinal lymph node metastasis from anal canal carcinoma and rectal carcinoma. However, long-term outcomes of inguinal lymph node metastasis from rectal or anal canal adenocarcinoma are unclear, which we aimed to investigate in this study.

Methods

The study population included 31 consecutive patients with rectal or anal canal adenocarcinoma who underwent inguinal lymph node dissection with curative intent at the National Cancer Center Hospital from 1986 to 2017. Long-term outcomes were assessed and clinicopathologic variables analyzed for prognostic significance.

Results

Of the 31 patients, 12 patients had rectal adenocarcinoma and 19 patients had anal canal adenocarcinoma. Synchronous metastasis were observed in 14 patients and metachronous metastasis in 17 patients. After dissection of inguinal lymph node metastasis with curative intent, the 5-year overall survival rate was 55.2%, with 12 patients surviving for more than 5 years. Median survival time was 66.6 months. Multivariate analyses revealed that location of primary tumor (rectum versus anal canal) was not a prognostic factor, whereas lateral lymph node metastasis and histological findings were independent prognostic factors.

Conclusion

Given the good prognosis, inguinal lymph node metastasis in patients with rectal or anal canal adenocarcinoma appears to be regional rather than distant. If R0 resection can be achieved, inguinal lymph node dissection may be indicated for these patients.

Colorectal peritoneal metastases: Optimal management review

The peritoneum is a common site of dissemination for colorrectal cancer, with a poorer prognosis than other sites of metastases. In the last two decades, it has been considered as a locoregional disease progression and treated as such with curative intention treatments. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is the actual reference treatment for these patients as better survival results have been reached as compared to systemic chemotherapy alone, but its therapeutic efficacy is still under debate. Actual guidelines recommend that the management of colorectal cancer with peritoneal metastases should be led by a multidisciplinary team carried out in experienced centers and consider CRS + HIPEC for selected patients. Accumulative evidence in the last three years suggests that this is a curative treatment that may improve patients disease-free survival, decrease the risk of recurrence, and does not increase the risk of treatment-related mortality. In this review we aim to gather the latest results from referral centers and opinions from experts about the effectiveness and feasibility of CRS + HIPEC for treating peritoneal disease from colorectal malignancies.

Introducing the eighth edition of the tumor-node-metastasis classification as relevant to colorectal cancer, anal cancer and appendiceal cancer: a comparison study with the seventh edition of the tumor-node-metastasis and the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma

BACKGROUND

The eighth edition of the tumor-node-metastasis classification of malignant tumors updates cancer staging according to the evidence accumulated in the last 8 years since the release of the tumor-node-metastasis seventh edition. This review focuses on the new staging system.

METHODS

The eight edition was compared with the seventh edition as well as the Japanese Classification of Colorcetal, Appendiceal, and Anal carcinoma ninth edition.

RESULTS

Of colon and rectum, the tumor-node-metastasis eighth edition expands the M category. Specifically, colorectal cancer with peritoneal metastasis is newly categorized as M1c, distinguishing it from M1a (metastasis to one organ) and M1b (metastasis to more than one organ). In the ninth edition of Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma, M1c is further subdivided into M1c1 (metastasis to the peritoneum without other organ involvement) and M1c2 (metastasis to the peritoneum with other organ involvement). In the T category, the tumor-node-metastasis eighth edition excludes high-grade dysplasia (intraepithelial carcinoma) from Tis; this differs from both the tumor-node-metastasis seventh edition and the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma ninth edition. In the N category, the tumor-node-metastasis eighth edition does not add the number of tumor deposits to the number of positive regional lymph nodes, whereas this number is added in the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma ninth edition. The definition of anal cancer is also modified considerably in the tumor-node-metastasis eighth edition; specifically, tumors of perianal skin defined as within 5 cm of the anal margin are also classified as anal canal carcinoma, external iliac lymph nodes become regional lymph nodes, and both N2 and N3 are abolished in the N category. With regard to appendix, Tis (low-grade appendiceal mucinous neoplasma) and tumor deposit(s) are newly introduced. Finally, the tumor-node-metastasis eighth edition offers a new structure, labeled a 'prognostic factors grid', which consists of prognostic factors for survival in both colorectal and anal cancer.

CONCLUSIONS

Staging classification is updated regularly, which clinicians should always catch up with.

Prognostic significance of doubling time in patients undergoing radical surgery for metachronous peritoneal metastases of colorectal cancer

PURPOSE

The doubling times of tumor volume and tumor markers are associated with the prognosis of liver or lung metastases from colorectal cancer (CRC). However, no studies have assessed peritoneal metastases. Therefore, we aimed to elucidate the association between doubling time and the prognosis of patients who underwent radical surgery for metachronous peritoneal metastases of CRC.

METHODS

We calculated the tumor doubling times (TDT) of peritoneal metastases and serum carcinoembryonic antigen-doubling times (CEA-DT) in 33 consecutive patients who underwent radical surgery for metachronous peritoneal metastases between January 2006 and April 2017. The impact of short TDT and CEA-DT on overall survival (OS) and relapse-free survival (RFS) was retrospectively reviewed.

RESULTS

In long TDT (> 137 days) group, the 5-year OS rate was 74.1% and median OS time was 6.6 years. In long CEA-DT (> 102 days) group, the 5-year OS rate was 50.0% and median OS time was 5.6 years. Conversely, in short TDT (≤ 137 days) and CEA-DT (≤ 102 days) group, the 5-year OS rates and median OS times were both 0.0% and 3.2 years, respectively. In the multivariate analysis, short TDT was an independent risk factor for poor RFS (P = 0.006) and OS (P = 0.010). Similarly, short CEA-DT was also a poor risk factor for RFS (P < 0.001) and OS (P = 0.012).

CONCLUSIONS

Short TDT and CEA-DT are independent risk factors for poor OS and RFS after surgery for metachronous peritoneal metastases of CRC. TDT and CEA-DT should be considered when selecting candidates for surgical resection.