There is no standard surgical management for rectal cancer with synchronous resectable liver metastases. The aim of this study was to assess the oncologic outcomes of an adaptative and individualized strategy considering the extension of both tumoral sites in the management of rectal cancer with synchronous resectable liver metastases.

From 2011 to 2020, all consecutive patients treated for low/midrectal cancer with resectable synchronous resectable liver metastases in 4 French centers were included. The choice of strategy was not systematic but tailored on a case-by-case basis to the extension of rectal cancer and liver metastases, prioritizing the most advanced site. The success of the strategy was defined as complete resection of both tumor sites.

Among 83 included patients, most had locally advanced rectal cancer (cT3T4 = 96%) and a median of 3 liver metastases. Forty patients underwent a rectum-first strategy, 31 a liver-first strategy, and 12 a simultaneous resection strategy. Complete resection rate of both sites was 82%. After a 43-month follow-up, median overall survival was 58 months. One- and 3-year survival rates were 94% and 73%, with no difference between strategies (P = .650). In multivariate analysis, the only prognostic factor for overall survival was complete resection of both sites (P = .011, hazard ratio, 0.321; 95% confidence interval, 0.135-0.768), with a median overall survival of 72 months in these patients.

Extent-based tailored strategy for rectal cancer with synchronous resectable liver metastases, on the basis of disease extension, allows high rates of complete resection and favorable long-term survival outcomes. This individualized approach maximizes potential for curative outcomes in patients with metastatic rectal cancer.

The optimal approach to the treatment of colorectal carcinoma and synchronous liver metastases remains controversial. The objective of this review was to analyze the outcomes of adopting the liver-first approach for the treatment of patients with colorectal cancer with synchronous hepatic metastases who initially underwent systemic chemotherapy and/or resection of the metastatic lesions and primary colorectal carcinoma.

This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The MEDLINE, EMBASE, LILACS, and Cochrane Central Register of Controlled Trials databases were searched for the identification and retrieval of eligible studies. Studies that included details of using the liver-first approach for the treatment of synchronous liver metastases of colorectal cancer and its outcomes, including the patients' survival data, were included. Proportional meta-analysis was performed using the random-effects restricted maximum likelihood method to summarize the three- and five-year overall survival and recurrence rates of the patients.

Eight hundred and fifty-five articles describing the results of studies on the liver-first approach were identified. Three independent reviewers screened the titles and abstracts of the articles and excluded 750 articles. Thereafter, 29 retrospective and comparative studies that met the inclusion criteria were included. No randomized controlled trials were identified in the database search.

Neoadjuvant treatment with systemic chemotherapy for hepatic metastasis can prepare a patient for resection of liver metastases, offering the opportunity for potentially curative treatment of synchronous hepatic metastases initially considered unresectable. The decision regarding the resection of primary colorectal carcinoma and liver metastases should be based on individualized patient response. Prospero database registration ID: CRD42022337047 (www.crd.york.ac.uk/prospero).

(1) Background: The liver-first approach may be indicated for colorectal cancer patients with synchronous liver metastases to whom preoperative chemotherapy opens a potential window in which liver resection may be undertaken. This study aims to present the data of feasibility and short-term outcomes in the liver-first approach. (2) Methods: A prospective observational study was performed in Spanish hospitals that had a medium/high-volume of HPB surgeries from 1 June 2019 to 31 August 2020. (3) Results: In total, 40 hospitals participated, including a total of 2288 hepatectomies, 1350 for colorectal liver metastases, 150 of them (11.1%) using the liver-first approach, 63 (42.0%) in hospitals performing <50 hepatectomies/year. The proportion of patients as ASA III was significantly higher in centers performing ≥50 hepatectomies/year (difference: 18.9%; p = 0.0213). In 81.1% of the cases, the primary tumor was in the rectum or sigmoid colon. In total, 40% of the patients underwent major hepatectomies. The surgical approach was open surgery in 87 (58.0%) patients. Resection margins were R0 in 78.5% of the patients. In total, 40 (26.7%) patients had complications after the liver resection and 36 (27.3%) had complications after the primary resection. One-hundred and thirty-two (89.3%) patients completed the therapeutic regime. (4) Conclusions: There were no differences in the surgical outcomes between the centers performing <50 and ≥50 hepatectomies/year. Further analysis evaluating factors associated with clinical outcomes and determining the best candidates for this approach will be subsequently conducted.

Metastatic gastrointestinal cancer is not an uncommon situation, especially for pancreatic, gastric, and colorectal cancers. In this setting, few data are available on the impact of the treatment of the primary tumour. Oligometastatic disease is associated with longer survival in comparison with more advanced disease. Metastasis-directed therapy, such as stereotactic body radiotherapy, seems related to better outcomes, but the level of evidence is low. In most tumour locations, prospective data are very scarce and inclusion in ongoing trials is strongly recommended.

Specific studies on stage IV rectal cancer are lacking. The aim of this study is to describe the current status of rectum-first approach (RFA), liver-first approach (LFA) and simultaneous approach (SA) in these patients.

A systematic review was performed on PubMed, EMBASE and Cochrane including studies published from January 2005 to January 2021. Studies on colon cancer only, colon and rectal cancer without distinction, extrahepatic metastases at diagnosis, or case reports/letters were excluded. Main outcomes were 5-yr overall survival (OS) and treatment completion rates.

22 studies were included for a total of 1,653 patients. 77% of the studies were retrospective and mainly (59%) reported one treatment approach. The primary endpoint was declared in 27% of the studies. Irrespective of treatment approaches, the 5-yr OS rate was reported in 72% of the studies. The 5-yr OS rates ranged from 38.5% to 75% for LFA, from 28% and 80% for RFA and from 28.2% to 77.3% for SA. Treatment completion rates ranged from 50% to 100% for LFA, from 37% to 100% for RFA, and from 66% to 100% for SA.

The wide heterogeneity of the results reflects that the therapeutic strategy in this setting is a case-by-case multidisciplinary decision and depends on several patient-specific features.

Rectal sparing is an option for some rectal cancers with complete or good response after chemoradiotherapy (CRT); however, it has never been evaluated in patients with metastases. We assessed long-term outcomes of a rectal-sparing approach in a liver-first strategy for patients with rectal cancer with resectable liver metastases.

We examined patients who underwent an organ-sparing approach for rectal cancer with synchronous liver metastases using a liver-first strategy during 2010-2015 (n = 8). Patients received primary chemotherapy and pelvic CRT. Liver surgery was performed during the interval between CRT completion and rectal tumor re-evaluation. Clinical and oncological characteristics and long-term outcomes were assessed.All patients underwent liver metastatic resection with curative intent. The R0 rate was 100%. Six and two patients underwent local excision and a watch-and-wait (WW) approach, respectively. All patients had T3N1 tumors at diagnosis and had good clinical response after CRT. The median survival time was 60 (range, 14-127) mo. Three patients were disease free for 5, 8, and 10 years after the procedure. Five patients developed metastatic recurrence in the liver (n = 5) and/or lungs (n = 2). Only one patient developed local recurrence concurrent with metastatic recurrence 24 mo after the WW approach. Two patients died during follow-up.

The results suggest good local control in patients undergoing organ-sparing strategies for rectal cancer with synchronous liver metastasis. Prospective trials are required to validate these data and identify good candidates for these strategies.

For patients with synchronous liver metastases (LM) from rectal cancer, a consensus on surgical sequencing is lacking. We compared outcomes between the reverse (hepatectomy first), classic (primary tumor resection first), and combined (simultaneous hepatectomy and primary tumor resection) approaches.

A prospectively maintained database was queried for patients with rectal cancer LM diagnosed before primary tumor resection who underwent hepatectomy for LM from January 2004 to April 2021. Clinicopathological factors and survival were compared between the three approaches.

Among 274 patients, 141 (51%) underwent the reverse approach; 73 (27%), the classic approach; and 60 (22%), the combined approach. Higher carcinoembryonic antigen level at LM diagnosis and higher number of LM were associated with the reverse approach. Combined approach patients had smaller tumors and underwent less complex hepatectomies. More than eight cycles of pre-hepatectomy chemotherapy and maximum diameter of LM > 5 cm were independently associated with worse overall survival (OS) (p = 0.002 and 0.027, respectively). Although 35% of reverse-approach patients did not undergo primary tumor resection, OS did not differ between groups. Additionally, 82% of incomplete reverse-approach patients ultimately did not require diversion during follow-up. RAS/TP53 co-mutation was independently associated with lack of primary resection with the reverse approach (odds ratio: 0.16, 95% CI 0.038-0.64, p = 0.010).

The reverse approach results in survival similar to that of combined and classic approaches and may obviate primary rectal tumor resections and diversions. RAS/TP53 co-mutation is associated with a lower rate of completion of the reverse approach.

The optimal management of rectal cancer with synchronous liver metastases remains debatable. Thus, we propose an optimised liver-first (OLF) strategy that combines concomitant pelvic irradiation with hepatic management. This study aimed to evaluate the feasibility and oncological quality of the OLF strategy.

Patients underwent systemic neoadjuvant chemotherapy followed by preoperative radiotherapy. Liver resection was performed in one step (between radiotherapy and rectal surgery) or in two steps (before and after radiotherapy). The data were collected prospectively and analysed retrospectively as intent to treat.

Between 2008 and 2018, 24 patients underwent the OLF strategy. The rate of treatment completion was 87.5%. Three patients (12.5%) did not proceed to the planned second-stage liver and rectal surgery because of progressive disease. The postoperative mortality rate was 0%, and the overall morbidity rates after liver and rectal surgeries were 21% and 28.6%, respectively. Only two patients developed severe complications. Liver and rectal complete resection was performed in 100% and 84.6%, respectively. A rectal-sparing strategy was performed in 6 patients who underwent local excision (n = 4) or a watch and wait strategy (n = 2). Among patients who completed treatment, the median overall and disease-free survivals were 60 months (range 12-139 months) and 40 months (range 10-139 months), respectively. Eleven patients (47.6%) developed recurrence, among whom five underwent further treatment with curative intent.

The OLF approach is feasible, relevant, and safe. Organ preservation was feasible for a quarter of patients and may be associated with reduced morbidity.

Patients presenting with synchronous colorectal liver metastases are increasingly being considered for a curative treatment, and the liver-first approach is gaining popularity in this context. However, little is known about the completion rates of the liver-first approach and its effects on survival.

A systematic review and meta-analysis of liver-first strategy for colorectal liver metastasis. The primary outcome was an assessment of the completion rates of the liver-first approach. Secondary outcomes included overall survival, causes of non-completion, and clinicopathologic data.

Seventeen articles were amenable for inclusion and the total study population was 1041. The median completion rate for the total population was 80% (range 20-100). The median overall survival for the completion and non-completion groups was 45 (range 12-69) months and 13 (range 10.5-25) months, respectively. Metadata showed a significant survival benefit for the completion group, with a univariate hazard ratio of 12.0 (95% confidence interval, range 5.7-24.4). The major cause of non-completion (76%) was liver disease progression before resection of the primary tumor. Pearson tests showed significant negative correlation between median number of lesions and median size of the largest metastasis and completion rate.

The liver-first approach offers a complete resection to most patients enrolled, with an overall survival benefit when completion can be assured. One-fifth fails to return to intended oncologic therapy and the major cause is interim metastatic progression, most often in the liver. Risk of non-completion is related to a higher number of lesions and large metastases. The majority of studies stem from primary rectal cancers, which may influence on the return to intended oncologic therapy as well.PROSPERO id no: 170459.

The optimal timing of surgery in case of synchronous presentation of colorectal cancer and liver metastases is still under debate. Staged approach, with initial colorectal resection followed by liver resection (LR), or even the reverse, liver-first approach in specific situations, is traditionally preferred. Simultaneous resections, however, represent an appealing strategy, because may have perioperative risks comparable to staged resections in appropriately selected patients, while avoiding a second surgical procedure. In patients with larger or multiple synchronous presentation of colorectal cancer and liver metastases, simultaneous major hepatectomies may determine worse perioperative outcomes, so that parenchymal-sparing LR should represent the most appropriate option whenever feasible. Mini-invasive colorectal surgery has experienced rapid spread in the last decades, while laparoscopic LR has progressed much slower, and is usually reserved for limited tumours in favourable locations. Moreover, mini-invasive parenchymal-sparing LR is more complex, especially for larger or multiple tumours in difficult locations. It remains to be established if simultaneous resections are presently feasible with mini-invasive approaches or if we need further technological advances and surgical expertise, at least for more complex procedures. This review aims to critically analyze the current status and future perspectives of simultaneous resections, and the present role of the available mini-invasive techniques.

We aimed to explore the prognostic value of primary tumor and specific metastases excision on survival among patients with stage IV colorectal cancer (CRC) in the Surveillance, Epidemiology, and End Results (SEER) database.

Patients with stage IV CRC were selected using SEER database between 2010 and 2013. Survival rate was calculated according to the Kaplan-Meier method, and differences between curves were tested by the log-rank test. Cox proportional hazards model was used in the multivariable analysis.

Included in this study were 27 878 patients with distant metastatic CRC. Among the single organ site of metastatic CRC, patients with solitary metastasis of lung showed the highest median overall survival (OS). Both primary and metastatic sites surgical resection for patients with liver, lung, and simultaneous liver and lung metastases had better median OS. Age younger than 65 years, Asian and Pacific Islander, distal colon and rectum, and palliative primary tumor and metastatic lesions resection were associated with better OS after multivariate analysis. Palliative primary tumor and metastatic lesions resection had a significant survival benefit compared with nonsurgical group in selected patients.

These findings support the use of preemptive surgery in the management of highly selected metastatic CRC patients.

The only possibility for cure in patients with colon adenocarcinoma (CAC) with isolated liver metastases (ILM) is resection of both primary and metastatic tumors. Little is known about the implication of the sequence in which a colectomy and hepatectomy are performed on outcomes. This study analyzes whether resection sequence impacts clinical outcomes.

The National Cancer Database was queried for CAC cases with hepatic metastases from 2010-2015 with exclusion of extrahepatic metastases. We compared patients treated with a liver-first approach (LFA) to those treated with a colectomy-first or simultaneous approach using Kaplan Meier and multivariable Cox proportional hazards analysis.

In 21,788 CAC patients identified, the LFA was uncommon (2%), but was associated with higher rates of completion resection of remaining tumor (41% vs. 22%, P<0.001). Patients selected for LFA were younger, less comorbid, and more commonly received upfront chemotherapy (P<0.05). The LFA was associated with increased median survival [34 months, 95% CI (30.5-39.6 months) vs. 24 months, 95% CI (23.7-24.6 months), logrank P<0.001] and decreased risk of death [HR 0.783; 95% CI (0.67-0.89), P=0.001].

The LFA to CAC with synchronous ILM is uncommon but is associated with greater likelihood of receiving chemotherapy prior to surgery and increased survival in selected candidates.

With recommendation of surgical management in primary site, both the positive and negative lymph nodes (LNs) retrieved have been emphasized to predict prognosis in stage IV rectum cancer. Therefore, we attempt to compare the prognostic performance of American Joint Committee on Cancer (AJCC) N-stage relative to lymph node ratio (LNR), log odds of metastatic lymph nodes (LODDS), and N-score in stage IV rectal cancer.

Total 5,090 patients taken surgical resection of primary site in rectum cancer with distant metastasis were extracted from Surveillance, Epidemiology, and End Results Program (SEER) database. Harrell's C statistic (C-index) and Akaike's Information Criterion (AIC) were used to evaluate the discriminative ability of the different LN staging systems.

Of the 3,243 patients without radiotherapy, 82.46% (n=2,675) had been found with lymph nodes metastasis with median number of 16 lymph nodes collected (IQR: 11-22). Modeled as categorical cutoff variables for further clinical usage, when number of LNs was between 12 and 25 (C-index: 0.5997, AIC: 1,698.015), 8^th AJCC N-stage outperformed other three schemas with increasing C-index and less AIC value. Assessed as continuous values, the LODDS shown as the best schemas with greatest discriminatory power (C-index: 0.5971, AIC: 3,680.017), generally. On the other hand, in the cohorts of other 1274 patients taken radiation, the median number of lymph nodes retrieved was 13 (IQR: 9-18). LODDS still remained remarkable performance as continuous (C-index: 0.5912; AIC: 1,058.765) and categorical variables (C-index: 0.5700; AIC: 1,061.703), while N-staging outperformed with less than 25 lymph nodes retrieved (LNs <12 C-index: 0.5678, AIC: 481.94; 12< LNs <25 C-index: 0.5933, AIC: 390.395).

When assessed as categorical variables, N-stage performed superiorly with adequate lymph nodes examined, whether the patients have got radiotherapy prior to surgery or not. LODDS showed, when assessed as a continuous variable, good discriminative ability and goodness of fit in predicting survival for stage IV rectum cancer patients regardless of radiation therapy status.

Venous thromboembolism (VTE) following rectal surgery is a significant and preventable cause of morbidity and mortality, yet the true prevalence is not well established. This systematic review and meta-analysis assessed the available literature and determined its prevalence following rectal surgery.

A systematic review assessed the prevalence of VTE following rectal surgery. In addition, we evaluated whether subgroups (open vs. minimally invasive or benign vs. malignant resections) impacted on its prevalence or rate of deep venous thrombosis (DVT) or pulmonary embolism (PE).

Thirty-eight studies met the predefined inclusion criteria. The aggregate prevalence of VTE following rectal surgery was 1.25% (95% CI 0.86-1.63), with DVT and PE occurring in 0.68% (95% CI 0.48-0.89) and 0.57% (95% CI 0.47-0.68) of patients. VTE following cancer and benign resection was 1.59% (95% CI 0.60-1.23 and 1.5% (95% CI 0.89-2.12) respectively. The prevalence of VTE in patients having minimally invasive resection was lower than those having open surgery [0.58% (16/2770) vs. 2.22% (250/11278); RR 0.54, 95% CI 0.33-0.86].

This review observed that there is sparse evidence on prevalence of VTE following rectal surgery. It provides aggregated data and analysis of available literature, showing overall prevalence is low, especially in those having minimally invasive procedures.

Synchronous colorectal carcinoma (SCRC) indicates more than one primary colorectal carcinoma (CRC) discovered at the time of initial presentation, accounts for 3.1%-3.9% of CRC, and may occur either in the same or in different colorectal segments. The accurate preoperative diagnosis of SCRC is difficult and diagnostic failures may lead to inappropriate treatment and poorer prognosis. SCRC requires colorectal resections tailored to individual patients, based on the number, location, and stage of the tumours, from conventional or extended hemicolectomies to total colectomy or proctocolectomy, when established predisposing conditions exist. The overall perioperative risks of surgery for SCRC seem to be higher than for solitary CRC. Simultaneous colorectal and liver resection represents an appealing surgical strategy in selected patients with CRC and synchronous liver metastases (CRLM), even though the cumulative risks of the two procedures need to be adequately evaluated. Simultaneous resections have the noticeable advantage of avoiding a second laparotomy, give the opportunity of an earlier initiation of adjuvant therapy, and may significantly reduce the hospital costs. Because an increasing number of recent studies have shown good results, with morbidity, perioperative hospitalization, and mortality rates comparable to staged resections, simultaneous procedures can be selectively proposed even in case of complex colorectal resections, including those for SCRC and rectal cancer. However, in patients with multiple bilobar CRLM, major hepatectomies performed simultaneously with colorectal resection have been associated with significant perioperative risks. Conservative or parenchymal-sparing hepatectomies reduce the extent of hepatectomy while preserving oncological radicality, and may represent the best option for selected patients with multiple CRLM involving both liver lobes. Parenchymal-sparing liver resection, instead of major or two-stage hepatectomy for bilobar disease, seemingly reduces the overall operative risk of candidates to simultaneous colorectal and liver resection, and may represent the most appropriate surgical strategy whenever possible, also for patients with advanced SCRC and multiple bilobar liver metastases.

The prognosis of patients with rectal cancer and synchronous liver metastasis has improved thanks to chemotherapy and rectal and liver surgery progresses. However, there is no consensus about optimal management and practices remain heterogeneous. A curative treatment may be considered for 20 to 30% of patients with complete resection of metastasis and primary tumor after induction chemotherapy. To this end, a primary optimal evaluation by a multidisciplinary board including hepatic and colorectal surgeons is crucial. The therapeutic strategy associates chemotherapy, radiotherapy, hepatic and rectal surgery. The most threatening site guides the sequence of treatments. If hepatic resectability is uncertain, a "liver first" strategy associating induction chemotherapy and hepatic surgery is preferred. In non-resectable metastatic cases, chemotherapies with targeted therapies might lead to secondary resection for 30% of patients (conversion). This has changed our practice and triggers reconsidering resectability after chemotherapy. When metastases remain non-resectable, additional treatment focusing on primary tumor should control pelvic symptoms otherwise hardly impacting quality of life. Rectal surgery, short-course radiotherapy (5×5Gy), conformational long-course chemoradiotherapy or intensity-modulated radiation therapy with dose escalation are options discussed in this review.

There is debate as to the correct treatment algorithm sequence for patients with locally advanced rectal cancer with liver metastases. The aim of the study was to assess safety, resectability and survival after a modified 'liver-first' approach.

This was a retrospective study of patients undergoing preoperative radiotherapy for the primary rectal tumour, followed by liver resection and, finally, resection of the primary tumour. Short-term surgical outcome, overall survival and recurrence-free survival are reported.

Between 2009 and 2013, 45 patients underwent liver resection after preoperative radiotherapy. Thirty-four patients (76%) received neoadjuvant chemotherapy, 24 (53%) concomitant chemotherapy during radiotherapy and 17 (43%) adjuvant chemotherapy. The median time interval from the last fraction of radiotherapy to liver resection and rectal surgery was 21 (range 7-116) and 60 (range 31-156) days, respectively. Rectal resection was performed in 42 patients but was not performed in one patient with complete response and two with progressive metastatic disease. After rectal surgery three patients did not proceed to a planned second stage liver (n = 2) or lung (n = 1) resection due to progressive disease. Clavien-Dindo ≥Grade III complications developed in 6.7% after liver resection and 19% after rectal resection. The median overall survival and recurrence-free survival in the patients who completed the treatment sequence (n = 40) were 49.7 and 13.0 months, respectively. Twenty of the 30 patients who developed recurrence underwent further treatment with curative intent.

The modified liver-first approach is safe and efficient in patients with locally advanced rectal cancer and allows initial control of both the primary tumour and the liver metastases.

The optimal sequence of surgery for rectal cancer (RC) with synchronous liver metastases (SLM) is controversial.

The primary objective was to explore differences between the rectum first (RF) and the liver first strategy (LF) to achieve the complete resection (CR) of both tumors.

Patients diagnosed of RC with resectable or potentially resectable SLM were included. Data collected prospectively were analyzed with an intention-to-treat perspective, adjusting for between-sample differences (propensity score). The complete resection rate (CRR) was the main outcome variable.

During a 5-year period, 23 patients underwent the LF strategy and 24 patients the RF strategy. Median overall survival (OS) was 32 months in the LF group and 41 months in the RF group (p = 0.499), and was 51 and 17 months, respectively, for patients achieving or not achieving CR of both tumors (p < 0.001). CRR's were 65% in liver first group and 63% in rectum first group, (p = 0.846). No between-strategy differences in morbidity or duration of treatment were observed.

This study supports the notion that the achievement of CR of RC and SLM should be the goal of oncological treatment. Both RF and LF strategies are feasible and safe, but no between-strategy differences have been found in the CRR.

The recent advent of more effective chemotherapy and the development of surgical procedures have expanded the pool of resectable patients with colorectal liver metastases (CLM). Two-stage hepatectomy (TSH), associated liver partition and portal vein ligation for staged hepatectomy (ALPPS), and ultrasound-guided enhanced one-stage hepatectomy (e-OSH) are the surgical solutions proposed for these patients, but the range of indications for these procedures vary from institution to institution.

The advantages and disadvantages of each approach are herein discussed. Patients who drop out between the staged operations of TSH limit its success rate, although predictive scores may help with patient selection and thereby optimize the results. Safety and oncological suitability are concerns to be addressed when considering ALPPS. These concerns notwithstanding, ALPPS has introduced an innovative concept in surgery: the monosegmental remnant liver. Studies involving e-OSH have proven the oncological suitability of tumor exposure once the CLM is detached from major intrahepatic vessels. This finding could expand the indications for e-OSH, although the technical challenges that it entails limit its spread among the surgical community. The liver-first approach involves the clearance of tumors from the liver before the colorectal primary is tackled. This approach fully justifies the complexity of e-OSH.

Predictive scores limiting the interstage dropout of TSH, partial and monosegmental ALPPS, and R1 vascular e-OSH justified by solid long-term results represent new insights that could help refne the patient assignment to each of these approaches. Additionally, liver transplantation is an emerging treatment for CLM that should be taken into account.

This article outlines the current Australian multidisciplinary treatment of synchronous metastatic colorectal adenocarcinoma and assesses the factors that influence patient outcome.

This is a retrospective analysis of the prospective 'Treatment of Recurrent and Advanced Colorectal Cancer' registry, describing the patient treatment pathway and documenting the extent of disease, resection of the colorectal primary and metastases, chemotherapy and biological therapy use. Cox regression models for progression-free and overall survival were constructed with a comprehensive set of clinical variables. Analysis was intentionn-ton-treat, quantifying the effect of treatment intent decided at the multidisciplinary team meeting (MDT).

One thousand one hundred and nine patients presented with synchronous metastatic disease between July 2009 and November 2015. Median follow-up was 15.8 months; 4.4% (group 1) had already curative resections of primary and metastases prior to MDT, 22.2% (group 2) were considered curative but were referred to MDT for opinion and/or medical oncology treatment prior to resection and 70.2% were considered palliative at MDT (group 3). Overall, 83% received chemotherapy, 55% had their primary resected and 23% had their metastases resected; 13% of resections were synchronous, 20% were staged with primary resected first and 62% had only the colorectal primary managed surgically. Performance status, metastasis resection (R0 versus R1 versus R2 versus no resection), resection of the colorectal primary and treatment intent determined at MDT were the most significant factors for progression-free and overall survival.

This is the largest Australian series of synchronous metastatic colorectal adenocarcinoma and offers insight into the nature and utility of contemporary practice.