The Prognostic Relevance of Histological Subtype in Patients With Peritoneal Metastases From Colorectal Cancer: A Nationwide Population-Based Study

INDEPSO-ISPSM Consensus on Peritoneal Malignancies: Management of Colorectal Peritoneal Metastases

PURPOSE

This manuscript reports the results of the Indian Network for Development of Peritoneal Surface Oncology and Indian Society of Peritoneal Surface Malignancies (INDEPSO-ISPSM) consensus that aimed to provide recommendations for some important aspects management of patients with colorectal peritoneal metastases (CPM) and address some issues unique to India.

METHODS

The modified Delphi technique was used with two rounds of voting. There were 29 questions on nine main topics-the role of cytoreductive surgery (CRS), patient selection for CRS, preoperative workup, role of systemic chemotherapy (SC), CPM with other visceral metastases, molecular profile, hyperthermic intraperitoneal chemotherapy (HIPEC) and other modalities of intraperitoneal chemotherapy (IPC), prophylactic/preventive strategies, and surveillances after CRS. A consensus was achieved if anyone option received >70 votes (strong consensus >90%).

RESULTS

Forty-eight surgical (n = 41) and gastrointestinal (n = 7) oncologists were invited; 44 agreed to participate. The response rate was 95.4% (42/44) in round 1 and 93.1% (41/44) in round 2. Overall, a consensus was achieved on 23/29 (79.3%) questions (strong consensus on 6/29 [20.6%]). The panel strongly recommended considering surgery for limited CPM with limited liver metastases (92.5%), not altering the surgical approach in patients with KRAS mutations (91.67%), and limiting the use of IPC for unresectable CPM outside clinical trials (95%). Adjuvant SC was recommended for all patients undergoing CRS (89.47%). CRS is a therapeutic option for selected patients with CPM including those with metachronous CPM (79.49) and signet ring cell cancers (76.92%). HIPEC was recommended outside clinical trials only for patients with peritoneal cancer index 11-15(80%).

CONCLUSION

The panel recommended CRS for most indications but was very selective in recommending HIPEC and IPC outside clinical trials. These recommendations should be a useful resource in clinical decision making for clinicians treating CPM in India and regions with a similar sociodemographic background.

Non-curative surgical oncology: postoperative needs and preferences

OBJECTIVE

When intended curative cancer surgery is not completed, the postoperative transition to palliative care represents a prognostic landmark to patients and their families. In patients referred for highly specialised surgery for peritoneal metastases from the intestinal tract and ovaries, surgery is not performed in approximately 25%. Still, little is known of their postoperative needs and preferences.

METHODS

We performed 14 qualitative research interviews with 12 patients (four men and eight women, aged 41-85 years) undergoing surgery for peritoneal metastases; five of these were together with a relative. Five of the participants had ovarian, and seven had colorectal cancer (four men and seven women). The interviews followed a semistructured interview guide, were audio recorded, transcribed verbatim and analysed using meaning condensation.

RESULTS

Patients accepted the surgeon's decision of refraining from the intended surgery. During the postoperative period, when realising the prognostic consequences, their needs changed rapidly, in some cases from day to day, and gradually they developed a reoriented focus on their lives. The findings were framed by two themes dealing with 'Change in treatment strategy' and 'Physical and psychosocial aspects of not undergoing curative surgery'.

CONCLUSION

When curative cancer surgery is not completed as intended, patient-centred communication is essential for patients' psychosocial reorientation and quality of life. Further, to support their well-being and action competences, patients have a need for basic supportive care and physical restitution. Finally, high-quality postoperative palliative care needs to be coordinated, which requires staff training and reorganisation of pathways.

Systematic review of risk factors, prognosis, and management of colorectal signet-ring cell carcinoma

BACKGROUND

Colorectal signet-ring cell carcinoma (CSRCC) is a rare clinical entity which accounts for approximately 1% of all colorectal cancers. Although multiple studies concerning this specific topic have been published in the past decades, the pathogenesis, associated risk factors, and potential implications on treatment are still poorly understood. Besides the low incidence, historically confusing histological criteria have resulted in confusing data. Nevertheless, the rising incidence of CSRCC along with relatively young age at presentation and associated dismal prognosis, highlight the actual interest to synthesize the known literature regarding CSRCC.

AIM

To provide an updated overview of risk factors, prognosis, and management of CSRCC.

METHODS

A literature search in the MEDLINE/PubMed database was conducted with the following search terms used: 'Signet ring cell carcinoma' and 'colorectal'. Studies in English language, published after January 1980, were included. Studies included in the qualitative synthesis were evaluated for content concerning epidemiology, risk factors, and clinical, diagnostic, histological, and molecular features, as well as metastatic pattern and therapeutic management. If possible, presented data was extracted in order to present a more detailed overview of the literature.

RESULTS

In total, 67 articles were included for qualitative analysis, of which 54 were eligible for detailed data extraction. CSRCC has a reported incidence between 0.1%-2.4% and frequently presents with advanced disease stage at the time of diagnosis. CSRCC is associated with an impaired overall survival (5-year OS: 0%-46%) and a worse stage-corrected outcome compared to mucinous and not otherwise specified adenocarcinoma. The systematic use of exploratory laparoscopy to determine the presence of peritoneal metastases has been advised. Surgery is the mainstay of treatment, although the rates of curative resection in CSRCC (21%-82%) are lower compared to those in other histological types. In case of peritoneal metastasis, cytoreductive surgery with hyperthermic intraperitoneal chemotherapy should only be proposed in selected patients.

CONCLUSION

CSRCC is a rare clinical entity most often characterized by young age and advanced disease at presentation. As such, diagnostic modalities and therapeutic approach should be tailored accordingly.

Clinical and Histopathologic Features of 35 Patients Treated for Colorectal Peritoneal Metastases Who Survived 5 Years

BACKGROUND

Currently, patients with a limited extent of peritoneal metastases from colon and rectal cancer are treated by cytoreductive surgery combined with perioperative chemotherapy performed at experienced centers.

OBJECTIVE

To statistically evaluate features that may impact survival of ≥5 years. These data are used in the risk/benefit analyses performed by the multidisciplinary team.

DESIGN

This was a retrospective review of a prospective database.

SETTINGS

This single-institution study was conducted at an academic center.

PATIENTS

All patients who had biopsy-proven colon or rectal peritoneal metastases treated by systemic chemotherapy, complete cytoreductive surgery, and perioperative surgery were included.

MAIN OUTCOME MEASURES

The primary outcomes measured were the clinical-, histologic-, and treatment-related features that had an impact on 5-year survival.

RESULTS

From 131 patients who had complete cytoreduction, 35 patients (26.7%) were identified as 5-year survivors. The median survival time was 27 months. The median age was 50.5 (range, 25-80) years. By univariant analysis, an absence of lymph node involvement at the time of primary colorectal cancer resection (HR 1.899 [95% CI, 1.064-3.388]; p = 0.03), complete or near-complete response to neoadjuvant chemotherapy (HR 0.251 [95% CI, 0.092-0.684]; p = 0.007), peritoneal cancer index ≤17 (HR 0.509 [95% CI, 0.329-0.788]; p = 0.002), complete visible resection of disease indicated by the completeness of cytoreduction score of 0 (HR 0.412 [95% CI, 0.224-0.756]; p = 0.004), and well-differentiated tumor (HR 0.34 [95% CI, 0.157-0.737]; p = 0.006) were significantly associated with ≥5 years survival.

LIMITATIONS

Limitations include its retrospective nature, unmeasured confounders, and data from a single institution.

CONCLUSIONS

The tumor biology as revealed by lymph node status and tumor differentiation plus extent of disease as measured by the response to neoadjuvant chemotherapy, peritoneal cancer index, and no visible residual disease indicated a favorable outcome. See Video Abstract at http://links.lww.com/DCR/C62 .

CARACTERSTICAS CLNICAS E HISTOPATOLGICAS EN PACIENTES TRATADOS POR METASTASIS PERITONEALES DE ORGEN COLORECTAL Y QUE SOBREVIVIERON AOS

ANTECEDENTES:Actualmente, los pacientes con extensión limitada de metástasis peritoneales de orígen colorectal son tratados mediante cirugía citorreductora asociada con una quimioterapia peri-peratoria realizadas en centros experimentados.OBJETIVO:Estúdio y evaluación estadística de las características que puedan impactar en la sobrevida de los pacientes a 5 años o más. Se utilizaron estos datos en el análisis de riesgo /beneficio realizados por un equipo multidisciplinario.DISEÑO:Revisión retrospectiva de una base de datos prospectiva.AJUSTES:Estudio realizado en una sola institución académica.PACIENTES:Todos aquellos que presentaban metástasis peritoneales de orígen colorectal, comprobadas por biopsia y tratadas con quimioterapia sistémica, cirugía peri-operatoria y citorreductora completas.MEDIDAS DE RESULTADO PRINCIPALES:Las medidads de resultados primarios fueron las características clínicas, histológicas y relacionadas con el tratamiento que tuvieron un impacto en la sobrevida a 5 años.RESULTADOS:De 131 pacientes que tuvieron una cirugía de citorreducción completa, 35 pacientes (26, 7%) fueron identificados como sobrevivientes a 5 años. La mediana de sobrevida fué de 27 meses. Se identificarion 16 varones. La mediana de edad fue de 50, 5 años con un rango de 25 a 80 años. Según análisis univariante, la ausencia de compromiso de los ganglios linfáticos en el momento de la resección del cáncer colorrectal primario (HR 1,899 (1,064, 3,388) p = 0,03), la respuesta completa o casi completa al tratamiento neoadyuvante con quimioterapia (HR 0,251 (0,092, 0,684) p = 0,007), el índice de cáncer peritoneal ≤17 (HR 0,509 (0,329, 0,788) p = 0,002), la resección completa y visible de la enfermedad indicada por la puntuación de citorreducción de 0 (HR 0,412 (0,224), 0,756) p = 0,004) y los tumores bien diferenciados (HR 0,34 (0,157, 0,737) p = 0,006) se asociaron significativamente con 5 o más años de sobrevida.LIMITACIONES:El estudio se encontró limitado por su naturaleza retrospectiva, por la no medida de factores de confusión y por los datos provenientes de una sola institución.CONCLUSIONES:La biología tumoral demostrada según el estado de los ganglios linfáticos y la diferenciación tumoral, agregada a la extensión de la enfermedad medida por la respuesta a la quimioterapia neoadyuvante, el índice de cáncer peritoneal y la ausencia visible de enfermedad residual, demostraron un resultado favorable. Consulte Video Resumen en http://links.lww.com/DCR/C62(Traducción-Dr. Xavier Delgadillo ).

The molecular biology of peritoneal metastatic disease

Peritoneal metastases are a common form of tumor cell dissemination in gastrointestinal malignancies. Peritoneal metastatic disease (PMD) is associated with severe morbidity and resistance to currently employed therapies. Given the distinct route of dissemination compared with distant organ metastases, and the unique microenvironment of the peritoneal cavity, specific tumor cell characteristics are needed for the development of PMD. In this review, we provide an overview of the known histopathological, genomic, and transcriptomic features of PMD. We find that cancers representing the mesenchymal subtype are strongly associated with PMD in various malignancies. Furthermore, we discuss the peritoneal niche in which the metastatic cancer cells reside, including the critical role of the peritoneal immune system. Altogether, we show that PMD should be regarded as a distinct disease entity, that requires tailored treatment strategies.

Microsatellite and RAS/RAF Mutational Status as Prognostic Factors in Colorectal Peritoneal Metastases Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) leads to prolonged survival for selected patients with colorectal (CRC) peritoneal metastases (PM). This study aimed to analyze the prognostic role of micro-satellite (MS) status and RAS/RAF mutations for patients treated with CRS.

METHODS

Data were collected from 13 Italian centers with PM expertise within a collaborative group of the Italian Society of Surgical Oncology. Clinical and pathologic variables and KRAS/NRAS/BRAF mutational and MS status were correlated with overall survival (OS) and disease-free survival (DFS).

RESULTS

The study enrolled 437 patients treated with CRS-HIPEC. The median OS was 42.3 months [95% confidence interval (CI), 33.4-51.2 months], and the median DFS was 13.6 months (95% CI, 12.3-14.9 months). The local (peritoneal) DFS was 20.5 months (95% CI, 16.4-24.6 months). In addition to the known clinical factors, KRAS mutations (p = 0.005), BRAF mutations (p = 0.01), and MS status (p = 0.04) were related to survival. The KRAS- and BRAF-mutated patients had a shorter survival than the wild-type (WT) patients (5-year OS, 29.4% and 26.8% vs 51.5%, respectively). The patients with micro-satellite instability (MSI) had a longer survival than the patients with micro-satellite stability (MSS) (5-year OS, 58.3% vs 36.7%). The MSI/WT patients had the best prognosis. The MSS/WT and MSI/mutated patients had similar survivals, whereas the MSS/mutated patients showed the worst prognosis (5-year OS, 70.6%, 48.1%, 23.4%; p = 0.0001). In the multivariable analysis, OS was related to the Peritoneal Cancer Index [hazard ratio (HR), 1.05 per point], completeness of cytoreduction (CC) score (HR, 2.8), N status (HR, 1.6), signet-ring (HR, 2.4), MSI/WT (HR, 0.5), and MSS/WT-MSI/mutation (HR, 0.4). Similar results were obtained for DFS.

CONCLUSION

For patients affected by CRC-PM who are eligible for CRS, clinical and pathologic criteria need to be integrated with molecular features (KRAS/BRAF mutation). Micro-satellite status should be strongly considered because MSI confers a survival advantage over MSS, even for mutated patients.

Clinicopathological Features and Survival of Signet-Ring Cell Carcinoma and Mucinous Adenocarcinoma of Right Colon, Left Colon, and Rectum

Histological subtype plays an important role in the different clinical characteristics and survival outcomes of patients with colorectal carcinoma (CRC). However, in previous studies, the influences of tumor locations and tumor stages have not been strictly controlled. This study focused on the assessment of the prognostic value of each histological subtype in different tumor locations and tumor stages of CRC. We used the Surveillance, Epidemiology, and End Results (SEER) database (1973-2011) to analyze 818,229 CRC patients with different clinical and pathological features, and analyzed the prognostic value of each histological subtype. Under the condition of stratification by tumor stage, signet-ring cell carcinoma (SRCC) presented the worst survival in each stage of right colon cancer (stage I, log-rank, p = 0.002, stages II, III, and IV, log-rank, p < 0.001), rectal cancer (RC) (log-rank, p < 0.001), and in stages II, III, and IV of left colon cancer (log-rank, p < 0.001). Multivariate survival analysis suggested SRCC subtype, male gender, age ≥ 70 years, tumor size ≥ 5 cm, stage progression, and poor differentiation were all significant factors worsening survival in CRC (p < 0.001, respectively). Mucinous adenocarcinoma (MC) histological subtype proved to be an independent protective factor for the prognosis of right colon cancer (p = 0.003). Overall, in our study, the results suggested SRCC had the worst survival among the three histological subtypes of CRC. MC was associated with favorable prognosis in right colon cancer but not with other tumor locations.

Impact of surgical staging for aggressive histology rectal cancers: a retrospective review

BACKGROUND

Poorly differentiated adenocarcinomas and signet ring adenocarcinomas are aggressive histological subtypes of rectal cancer with a high incidence of occult peritoneal metastasis.

METHODS

This was a retrospective review of aggressive histology of rectal cancer patients who underwent pre-treatment surgical staging as part of ovarian transposition or ostomy creation for diversion at a single tertiary cancer centre between January 2014 and December 2019.

RESULTS

A total of 117 patients underwent surgical staging and were deemed non-metastatic on imaging. Surgical staging led to the detection of metastasis in 29.9% of patients. This led to modification in treatment protocol in 20.5% and change in intent of therapy in 15.4%. The majority (80%) was found to have peritoneal disease with peritoneal carcinomatosis index <17. Only T4 disease predicted the presence of metastasis on surgical staging with an odds ratio of 2.69 (P = 0.035).

CONCLUSIONS

A significant proportion of patients with aggressive histology rectal cancers are upstaged after surgical staging. Further investigation of this tool for staging is warranted.

Clinicopathological factors and survival outcomes of signet-ring cell and mucinous carcinoma versus adenocarcinoma of the colon and rectum: a systematic review and meta-analysis

BACKGROUND

Histological subtypes of colorectal cancer may be associated with varied prognostic features. This systematic review and meta-analysis aimed to compare clinicopathological characteristics, recurrence and overall survival between colorectal signet-ring cell (SC) and mucinous carcinoma (MC) to conventional adenocarcinoma (AC).

METHODS

A literature search of MEDLINE, EMBASE, Ovid and Cochrane Library was performed for studies that reported data on clinicopathological and survival outcomes on SC and/or MC versus AC from January 1985 to May 2020. Meta-analysis was performed using random-effect models and between-study heterogeneity was assessed.

RESULTS

Thirty studies of 1,087,055 patients were included: 11,510 (1.06%) with SC, 110,179 (10.13%) with MC and 965,366 (88.81%) with AC. Patients with SC were younger than patients with AC (WMD - 0.47; 95% CI - 0.84 to -0.10; I2 88.6%; p = 0.014) and more likely to have right-sided disease (OR 2.12; 95% CI 1.72-2.60; I2 82.9%; p < 0.001). Locoregional recurrence at 5 years was more frequent in patients with SC (OR 2.81; 95% CI 1.40-5.65; I2 0.0%; p = 0.004) and MC (OR 1.92; 95% CI 1.18-3.15; I2 74.0%; p = 0.009). 5-year overall survival was significantly reduced when comparing SC and MC to AC (HR 2.54; 95% CI 1.98-3.27; I2 99.1%; p < 0.001 and HR 1.38; 95% CI 1.19-1.61; I2 98.6%; p < 0.001, respectively).

CONCLUSION

SC and MC are associated with right-sided lesions, advanced stage at presentation, higher rates of recurrence and poorer overall survival. This has strong implications towards surgical and oncological management and surveillance of colorectal cancer.

Status of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in patients with peritoneal carcinomatosis from colorectal cancer

Peritoneal carcinomatosis (PC) was previously considered an incurable disease with a poor survival outcome. As our understanding of its biology evolved, the paradigm of the management of PC from colorectal cancer (CRC) has changed, including the combination of macroscopic disease control, cytoreductive surgery (CRS), maximal regional chemotherapy to treat residual microscopic disease, and hyperthermic intraperitoneal chemotherapy (HIPEC). As with many surgical innovations, CRS with HIPEC has evolved faster than data to support it, leaving many skeptics and critics. This review highlights the recent evidence of current practice and outcome of CRS with HIPEC. Furthermore, it also summarizes the ongoing clinical trials and potential future progress of this treatment modality.

The Amount of Bifidobacterium Genus in Colorectal Carcinoma Tissue in Relation to Tumor Characteristics and Clinical Outcome

Evidence indicates a complex link between microbiota, tumor characteristics, and host immunity in the tumor microenvironment. In experimental studies, bifidobacteria appear to modulate intestinal epithelial cell differentiation. Accumulating evidence suggests that bifidobacteria may enhance the antitumor immunity and efficacy of immunotherapy. We hypothesized that the amount of bifidobacteria in colorectal carcinoma tissue might be associated with tumor differentiation and higher immune response to colorectal cancer. Using a molecular pathologic epidemiology database of 1313 rectal and colon cancers, we measured the amount of Bifidobacterium DNA in carcinoma tissue by a quantitative PCR assay. The multivariable regression model was used to adjust for potential confounders, including microsatellite instability status, CpG island methylator phenotype, long-interspersed nucleotide element-1 methylation, and KRAS, BRAF, and PIK3CA mutations. Intratumor bifidobacteria were detected in 393 cases (30%). The amount of bifidobacteria was associated with the extent of signet ring cells (P = 0.002). Compared with Bifidobacterium-negative cases, multivariable odd ratios for the extent of signet ring cells were 1.29 (95% CI, 0.74-2.24) for Bifidobacterium-low cases and 1.87 (95% CI, 1.16-3.02) for Bifidobacterium-high cases (Ptrend = 0.01). The association between intratumor bifidobacteria and signet ring cells suggests a possible role of bifidobacteria in determining distinct tumor characteristics or as an indicator of dysfunctional mucosal barrier in colorectal cancer.

Clinicopathologic Significance of CXCL12 and CXCR4 Expressions in Patients with Colorectal Cancer

Background

Colorectal cancer (CRC) is both a global and national burden, being the third most common malignancy in men and the second in women, worldwide. The prognosis of CRC is affected by various factors like the histological grade, angiolymphatic invasion, and distant metastases. Metastasis is an intricate process; one of the possible mechanisms is through the interaction of the chemokines CXCL12 and CXCR4. This study aims to reveal the expression patterns of CXCL12 and CXCR4 in CRC.

Methods

The quantitative expressions of CXCL12 and CXCR4 messenger RNA (mRNA) were evaluated in 32 patients with adenocarcinoma-type CRC. Real-time polymerase chain reaction (qRT-PCR) was performed on formalin-fixed tissues. CXCL12 and CXCR4's expressions, clinicopathologic features, and the treatment response to the CRC were analysed.

Results

All tumour tissues showed higher levels of both chemokines compared to normal colonic tissue. The expression of CXCL12 mRNA was higher in rectal location (p = 0.04) with a tendency to be higher in later stages (p = 0.15), while the expression of CXCR4 was lower in tumours with a lymphatic invasion (p = 0.02), compared to their counterparts. There was no difference in the expression of CXCL12 and CXCR4 according to the patients' ages, gender, tumour differentiation, or response to chemotherapy.

Conclusion

Our study demonstrated that the mRNA expression of CXCL12 was significantly correlated with rectal location. CXCR4 mRNA expression was inversely correlated in tumours with a lymphatic invasion.

Predictive value of peritoneal cancer index for survival in patients with mucinous peritoneal malignancies treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: a single centre experience

OBJECTIVES

This study investigated the correlation between the peritoneal carcinomatosis index (PCI) and patient outcome depending on the tumour type.

BACKGROUND

Peritoneal surface malignancy (PSM) treatment depends on tumour type. Mucinous PSM (m-PSM) is associated with a better prognosis than non-mucinous PSM (nm-PSM). The PCI's predictive ability has not yet been evaluated.

METHODS

We analysed 123 patients with PSM treated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) between 2008 and 2015. The m-PSM group (n = 75) included patients with appendiceal cancer (n = 15), colorectal cancer (n = 21), or low-grade appendiceal mucinous neoplasm (n = 39); the nm-PSM group (n = 48) included patients with gastric (n = 18) or colorectal (n = 30) cancer. The PCI's predictive ability was evaluated by multiple Cox-proportional hazard regression analysis and Kaplan-Meier curves.

RESULTS

The 5-year survival and PCI were higher in m-PSM patients (67.0%; 20.5 ± 12.1) than in nm-PSM patients (32.6%; p = 0.013; 8.9 ± 6.0; p < 0.001). Colorectal nm-PSM patients with PCI ≥16 had a worse 2-year survival (25.0%) vs. patients with PCI <16 (79.1%; log rank = 0.009), but no significant effect was observed in patients with m-PSM (66.7% vs. 68.1%; p = 0.935). Underlying disease (HR 5.666-16.240), BMI (HR 1.109), and PCI (HR 1.068) significantly influenced overall survival in all patients.

CONCLUSIONS

PCI is prognostic in nm-PSM, but not in m-PSM. CRS and HIPEC may benefit not only patients with low PCI, but also those with high PCI and m-PSM.

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

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

Cytoreduction and hyperthermic intraperitoneal chemotherapy (CS/HIPEC) in colorectal cancer: Evidence-based review of patient selection and treatment algorithms

Cytoreduction and heated intraperitoneal chemotherapy (CS/HIPEC) is increasingly utilized as a treatment strategy for patients with peritoneal metastases from various primary tumor sites. For this heterogenous procedure, related to patient characteristics, patient selection, and the extent of surgical completeness of cytoreduction, high level evidence (ex: multiple randomized controlled trials) is not available to support efficacy. This review of the available literature supporting application of the procedure, focusing on colorectal cancer, provides a summary of current evidence for patient selection and treatment algorithms based on patient presentation.

Oligometastatic Disease in the Peritoneal Space with Gastrointestinal Cancer

OBJECTIVES

Treatment options for patients with gastrointestinal cancer and oligometastastic disease remain the domain of the medical oncologist. However, in selected cases, attempts to remove or destroy the tumor burden seem appropriate.

BACKGROUND DATA

During the last decade, the treatment of localized and isolated tumor nodules, such as lung, liver or peritoneal metastasis, has changed. Previously, these patients with metastatic disease only received palliative chemotherapy. Combined treatment approaches and new techniques demonstrate that additional surgery to destroy or remove the metastases seem to be of major benefit to patients.

METHODS

The recently published important literature regarding peritoneal metastases and oligometastases in gastrointestinal cancer was analyzed.

RESULTS

The most important factor in the treatment of peritoneal metastases and in cytoreductive surgery is patient selection. Resection of peritoneal metastases should be considered. Hyperthermic intraperitoneal chemotherapy is feasible. However, further results of randomized trials are necessary. Several randomized trials are on the way and will be available in 1-2 years. Systemic chemotherapy alone as an adequate management plan for all sites of metastatic disease is not compatible with a high standard of care. Formulating an optimal plan combining re-operative surgery with regional plus systemic chemotherapy is a necessary task of the multidisciplinary team.

CONCLUSIONS

In oligometastastic disease of gastrointestinal cancer origin, the selection process is the most important factor for survival. Further studies are needed to determine optimal treatment options.

Histological subtype and systemic metastases strongly influence treatment and survival in patients with synchronous colorectal peritoneal metastases

BACKGROUND

Treatment possibilities for colorectal peritoneal metastases (PM) are increasing. It is however unclear how treatment choice and outcome are influenced by histological subtype and the presence of systemic metastases. Therefore, this study assessed the impact of histological subtype and systemic metastases on treatment choice and survival in patients with colorectal PM.

METHODS

This population-based study included patients with synchronous PM originating from colorectal adenocarcinoma (AC), mucinous adenocarcinoma (MC), or signet ring cell carcinoma (SRCC). Data of patients diagnosed between 2005 and 2014 were extracted from the National Cancer Registry (IKNL) of the Netherlands. Treatment strategy and survival were analyzed with logistic regression and cox proportional hazard analyses.

RESULTS

In total, 5516 patients were included, of whom 71.8% had an AC, 21.2% an MC, and 7.0% had an SRCC. The use of cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) was dependent on histological subtype and the presence of systemic metastases, and increased over time, especially in AC and MC patients. The relative survival gain of CRS + HIPEC, corrected for systemic metastases, was comparable in AC, MC, and SRCC patients (hazard ratio: 0.17, 0.21, and 0.13, respectively). Compared to supportive care only, the absolute survival gain was 30, 35, and 18 months, respectively. Systemic therapy improved survival in all histological subtypes.

CONCLUSIONS

Histological subtype and the presence of systemic metastases strongly influenced treatment choice and survival in patients with synchronous colorectal PM. These results can be used to optimize treatment strategy for patients with synchronous colorectal PM.