External multicentre validation of pseudomyxoma peritonei PSOGI-Ki67 classification.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare malignant disease. Adding of the Ki67 proliferation index to the PSOGI PMP classification provided two different subcategories of the extensive HG-PMP group (HG-PMP ≤15% and HG-PMP >15%) with different survival in a previous unicentric study. This study aims to carry out an external and multicentre validation of this new proposed classification. METHOD: It was a prospective analysis of samples from a historical and international cohort of patients. A representative area with higher cellular density was used to determine the Ki67%. The Ki67 proliferation index (%) was determined in all the HG-PMP patients. A Cox proportional hazard models and multivariable COX models were used. The Kaplan-Meier method and the two-tailed log-rank test were used to analyse the effect of different PSOGI-Ki67 categories on OS and DFS. Its predictive accuracy was analysed using Harrel's C-index and the ROC curve. The calibration was performed using the calibration plots matching. RESULTS: After exclusions, 349 patients were available for analysis. The 5-years OS were 86% for LG-PMP, 59% for HG-PMP≤15, 38% for HG-PMP>15 and 42% for SRC-PMP (p = 0.0001). The 5-years DFS were 49% for LG-PMP, 35% for HG-PMP≤15, 16% for HG-PMP>15 and 18% SRC-PMP (p = 0.0001). The discrimination capability of PSOGI-Ki67 was validated. CONCLUSION: the PSOGI-Ki67 classification discriminates and predicts the OS and DFS in patients with PMP dividing the HG-PMP category into two well-defined sub-categories. The Ki67 proliferation index should be incorporated routinely in the pathology report for these patients.

Impact of KRAS, BRAF and microsatellite instability status after cytoreductive surgery and HIPEC in a national cohort of colorectal peritoneal metastasis patients.

BACKGROUND: Patients with metastatic colorectal cancer (mCRC) carrying BRAF (mutBRAF) or KRAS mutation (mutKRAS) have an inferior prognosis after liver or lung surgery, whereas the prognostic role in the context of peritoneal metastasis (PM) after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been less investigated. METHODS: In total, 257 patients with non-appendiceal PM-CRC were included from the Norwegian National Unit for CRS-HIPEC. RESULTS: In total, 180 patients received CRS-HIPEC with Mitomycin C, 77 patients received palliative surgery only. In the CRS-HIPEC group, mutBRAF was found in 24.7%, mutKRAS 33.9% and double wild-type 41.4% without differences in survival. MSI was found in 29.3% of mutBRAF cases. Patients with mutBRAF/MSI had superior 5-year survival compared to mutBRAF with MSS (58.3% vs 25.2%, P = 0.022), and better 3-year disease-free survival (DFS) compared to mutKRAS (48.6% vs 17.2%, P = 0.049). Peritoneal Cancer Index and the number of lymph node metastasis were prognostic for OS, and the same two, location and gender prognostic for DFS in multivariate analysis. CONCLUSIONS: PM-CRC with CRS-HIPEC patients has a surprisingly high proportion of mutBRAF (24.7%). Survival was similar comparing mutBRAF, mutKRAS and double wild-type cases, whereas a small subgroup with mutBRAF and MSI had better survival. Patients with mutBRAF tumours and limited PM should be considered for CRS-HIPEC.

Beyond total mesorectal excision in locally advanced rectal cancer with organ or pelvic side-wall involvement.

BACKGROUND: In locally advanced rectal cancer (LARC), beyond total mesorectal excision (bTME) is often necessary to obtain complete resection (R0). The aim of this study was to identify prognostic determinants and compare morbidity and survival in LARC cases requiring bTME or TME surgery. METHOD: Single centre cohort study of LARC cases where all patients received neoadjuvant radiotherapy (n = 332). Data was registered prospectively in an institutional database linked to the National Registry. RESULTS: bTME surgery was performed in 224 patients, 171 with resections of adjacent organs (bTME-o group) and 53 with pelvic side-wall resections (bTME-pw group). TME surgery was performed in 108 patients. Six deaths occurred within 100 days and severe morbidity was registered in 23.8% of the whole cohort and in 25.4% of the bTME groups. The R0 rates were 93.5%, 84.2%, and 75.5% in the TME, bTME-o, and bTME-pw groups, respectively. Five-year disease free survival (DFS) was 67.3% (TME group), 54.5% (bTME-o group) and 48.7% (bTME-pw group), and five-year overall survival (OS) 78.7%, 69.0% and 60.4% respectively. Patients with involved resection margins (R1), high pT-stage, pN-positivity or poor response to neoadjuvant therapy were associated with inferior DFS and OS. CONCLUSION: In organ-threatening or infiltrating LARC, bTME surgery can be performed with low mortality and acceptable morbidity to obtain a good long-term outcome. Patients with pelvic side-wall infiltration were identified as a subgroup with increased risk of R1 resection and inferior long-term outcome.

Deep Pelvic Surgical Site Infection After Radiotherapy and Surgery for Locally Advanced Rectal Cancer.

BACKGROUND: High morbidity, increased mortality, and impaired long-term oncologic outcome have been reported after deep surgical site infection (SSI) in rectal cancer surgery. The rate, risk factors and consequences of deep SSI after (chemo)radiotherapy [(C)RT], and surgery for locally advanced rectal cancer (LARC) in a tertiary university hospital single centre cohort of 540 patients are presented. METHODS: Patients with LARC, operated between January 1, 2007 and December 31, 2015, were identified in the institutional prospective database. All patients had tumours threatening the mesorectal fascia or invading adjacent organs, with a high rate of T4 tumours (60 %), and all received (C)RT. Risk factors for deep SSI were calculated by multivariable logistic regression analysis. Morbidity data were assessed. Overall survival (OS) and disease-free survival (DFS) between patients with or without deep SSI were estimated. RESULTS: Of 540 patients, 104 (19 %) experienced a deep SSI, with the highest rate in the abdominoperineal resection (APR) group with 25 %. APR, good response to (C)RT (low tumour regression grade), age, and operative blood loss were identified as significant (P < 0.05) risk factors for deep SSI in multivariable analysis. No difference was found in OS (P = 0.995) or DFS (P = 0.568). Hospital stay increased with 5 days (P < 0.001), and complete wound healing at the 3-month follow-up decreased from 86 to 45 % (P < 0.001) after deep SSI. CONCLUSIONS: Deep SSI is a frequent and major complication after rectal surgery for LARC, with high morbidity, increased hospital stay and protracted wound healing. Interestingly, deep SSI did not influence long-term oncologic outcome.

Oxaliplatin-containing Preoperative Therapy in Locally Advanced Rectal Cancer: Local Response, Toxicity and Long-term Outcome.

AIMS: This non-randomised study was undertaken to examine oxaliplatin as possibly an intensifying component of sequential neoadjuvant therapy in locally advanced rectal cancer for improved local and metastatic outcome. MATERIALS AND METHODS: Ninety-seven patients (57 T2-3 cases, 40 T4 cases) received two cycles of the Nordic FLOX regimen (oxaliplatin 85 mg/m(2) day 1 and bolus 5-fluorouracil 500 mg/m(2) and folinic acid 100 mg days 1 and 2) before long-course chemoradiotherapy with concomitant oxaliplatin and capecitabine, followed by pelvic surgery. Treatment toxicity, local tumour response and long-term outcome were recorded. RESULTS: Good histologic tumour regression was obtained in 72% of patients. Implementing protocol-specific dose adjustments, tolerance was acceptable and 95% of patients received the total prescribed radiation dose. Estimated 5 year progression-free and overall survival were 61% and 83%, respectively. T4 stage was associated with an inferior local response rate, which again was highly associated with impaired long-term outcome. CONCLUSIONS: In this cohort of rectal cancer patients dominated by T4 and advanced T3 cases given sequential oxaliplatin-containing preoperative therapy with acceptable toxicity, high tumour response rates and overall survival were obtained, consistent with both local and systemic effects. However, tumour response and long-term outcome remained inferior for a significant number of T4 cases, suggesting that the T4 entity is biologically heterogeneous with subgroups of patients eligible for further individualisation of therapy.

Prophylactic mesh at end-colostomy construction reduces parastomal hernia rate: a randomized trial.

AIM: Parastomal hernia (PSH) is the most common complication of an end-colostomy and about one-quarter of patients need operative repair, which is often unsuccessful. A randomized trial was carried out to compare the results of using mesh or no mesh at the time of formation of a colostomy with the clinical identification of PSH as the primary outcome. METHOD: In this two-centre randomized trial (Oslo University Hospital and Sykehuset Innlandet Hospital Trust, Norway), patients with rectal cancer undergoing open pelvic surgery were randomized to receive a retromuscular synthetic mesh (study group, n = 32) or no mesh (control group, n = 26) at the time of end-colostomy formation. Postoperative follow up was not blinded and included clinical examination and routine CT. RESULTS: The median period of follow up was 40 (range: 84) months. There were no differences in demographic variables or complications between the study and control groups. PSH developed in two patients of the study group and in 12 of the control group [OR = 0.04 (95% CI: 0.01-0.30) and hazard ratio 0.134 (95% CI: 0.030-0.603); P < 0.001]. The number needed to treat to avoid one PSH was 2.5 patients. CT demonstrated an increase over time in the size of the fascial orifice in patients with PSH without mesh prophylaxis, in contrast to a stable size in patients with mesh and in the control patients who did not develop PSH. CONCLUSION: The retromuscular insertion of synthetic mesh at the time of formation of an end-colostomy reduced the risk of PSH.

MRI volumetry for prediction of tumour response to neoadjuvant chemotherapy followed by chemoradiotherapy in locally advanced rectal cancer.

OBJECTIVE: To investigate if MRI-assessed tumour volumetry correlates with histological tumour response to neoadjuvant chemotherapy (NACT) and subsequent chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC). METHODS: Data from 69 prospectively enrolled patients with LARC receiving NACT followed by CRT and radical surgery were analysed. Whole-tumour volumes were contoured in T2 weighted MR images obtained pre-treatment (VPRE), after NACT (VNACT) and after the full course of NACT followed by CRT (VCRT). VPRE, VNACT and tumour volume changes relative to VPRE, ΔVNACT and ΔVCRT were calculated and correlated to histological tumour regression grade (TRG). RESULTS: 61% of good histological responders (TRG 1-2) to NACT followed by CRT were correctly predicted by combining VPRE < 10.5 cm(3), ΔVNACT > -78.2% and VNACT < 3.3 cm(3). The highest accuracy was found for VNACT, with 55.1% sensitivity given 100% specificity. The volume regression after completed NACT and CRT (VCRT) was not significantly different between good and poor responders (TRG 1-2 vs TRG 3-5). CONCLUSION: MRI-assessed small tumour volumes after NACT correlated with good histological tumour response (TRG 1-2) to the completed course of NACT and CRT. Furthermore, by combining tumour volume measurements before, during and after NACT, more good responders were identified. ADVANCES IN KNOWLEDGE: MRI volumetry may be a tool for early identification of good and poor responders to NACT followed by CRT and surgery in LARC in order to aid more individualized, multimodal treatment.

Clinical significance of disseminated tumour cells in non-small cell lung cancer.

BACKGROUND: Early-stage non-small cell lung cancer (NSCLC) patients have a high risk of disease relapse despite curatively intended surgical resection, and the detection of tumour cells in the bone marrow could be one method of determining the presence of the disseminated disease in its early stages. METHODS: Bone marrow aspirates were collected from 296 patients at the time of surgery, and the presence of disseminated tumour cells was determined with the help of immunomagnetic selection (IMS) using the MOC31-antibody recognising EpCAM and with the help of standard immunocytochemistry (ICC) using the anti-cytokeratin (CK) antibodies AE1/AE3. RESULTS: Disseminated tumour cells were found in 152 of 252 (59%) bone marrow samples using IMS and in 25 of 234 (11%) samples using ICC. No association between the two detection methods was observed. The presence of EpCAM⁺ cells was not associated with any clinicopathological parameters, whereas a higher frequency of CK⁺ cells was found in patients with an advanced pT status. Disseminated tumour cells, as detected using IMS, had no prognostic impact. Patients with CK⁺ cells in the bone marrow had a reduced relapse-free survival, but the difference was not statistically significant. CONCLUSION: Our findings do not support the further development of DTC detection for clinical use in early-stage NSCLC. Future studies should include the molecular characterisation of DTCs, along with an attempt to identify subpopulations of cells with biological and clinical significance.

Evaluation of complete cytoreductive surgery and two intraperitoneal chemotherapy techniques in Pseudomyxoma peritonei.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a low-grade malignancy characterized by mucinous tumor on the peritoneal surface. Treatment involves cytoreductive surgery (CRS) to remove all macroscopic tumor and perioperative intraperitoneal chemotherapy (PIC) to eliminate remaining microscopic disease. PATIENTS AND METHODS: Between 1994 and 2009, 93 patients were treated at the Norwegian Radium Hospital with complete CRS and PIC. PIC was administered as early postoperative intraperitoneal chemotherapy (EPIC) using mitomycin C (MMC) and 5-fluoruracil (n = 48) and as hyperthermic intraperitoneal chemotherapy (HIPEC) using MMC (n = 45). Patients were classified into three histopathological subgroups: Disseminated peritoneal adenomucinosis (n = 57), peritoneal mucinous carcinomatosis (n = 21) and an intermediate group (n = 15). Tumor distribution by peritoneal cancer index (PCI) was PCI ≤ 10 (n = 31), PCI 11-20 (n = 29), PCI ≥ 21 (n = 33). RESULTS: Recurrence was diagnosed in 38 patients and 25 patients died during follow-up. Estimated 10-year overall survival (OS) was 69% and 10-year disease-free survival (DFS) was 47%. Mean OS was 154 months (95% CI 131-171) and median OS was not reached (follow-up median 85 months (3-207)). Low-grade malignant histology (p = 0.001) and female gender (p = 0.045) were associated with improved OS. Almost equal OS and DFS were observed between patients treated with EPIC and HIPEC. CONCLUSIONS: Patients treated for PMP with complete CRS and PIC achieved satisfactory long-term outcome. The most important prognostic factor was histopathological differentiation, but acceptable survival was observed even in patients with aggressive histology and extensive intraperitoneal tumor growth. Administration of EPIC and HIPEC was equally efficacious with respect to long-term outcome.

EMMPRIN is associated with S100A4 and predicts patient outcome in colorectal cancer.

BACKGROUND: Proteolytic enzymes and their regulators have important biological roles in colorectal cancer by stimulating invasion and metastasis, which makes these factors attractive as potential prognostic biomarkers. METHODS: The expression of extracellular matrix metalloproteinase inducer (EMMPRIN) was characterised using immunohistochemistry in primary tumours from a cohort of 277 prospectively recruited colorectal cancer patients, and associations with expression of S100A4, clinicopathological parameters and patient outcome were investigated. RESULTS: One hundred and ninety-eight samples (72%) displayed positive membrane staining of the tumour cells, whereas 10 cases (4%) were borderline positive. EMMPRIN expression was associated with shorter metastasis-free, disease-specific and overall survival in both univariate and multivariate analyses. The prognostic impact was largely confined to TNM stage III, and EMMPRIN-negative stage III patients had an excellent prognosis. Furthermore, EMMPRIN was significantly associated with expression of S100A4, and the combined expression of these biomarkers conferred an even poorer prognosis. However, there was no evidence of direct regulation between the two proteins in the colorectal cancer cell lines HCT116 and SW620 in siRNA knockdown experiments. CONCLUSION: EMMPRIN is a promising prognostic biomarker in colorectal cancer, and our findings suggest that it could be used in the selection of stage III patients for adjuvant therapy.

Disseminated tumour cells as a prognostic biomarker in colorectal cancer.

BACKGROUND: The study was performed to determine detection rate and prognostic relevance of disseminated tumour cells (DTC) in patients receiving curatively intended surgery for colorectal cancer (CRC). METHODS: The study population consisted of 235 patients with CRC prospectively recruited from five hospitals in the Oslo region. Bone marrow (BM) aspirates were collected at the time of surgery and the presence of DTC was determined by two immunological methods; immunomagnetic selection (using an anti-EpCAM antibody) and immunocytochemistry (using a pan-cytokeratin antibody). Associations between the presence of DTC and metastasis-free, disease-specific and overall survival were analysed using univariate and multivariate methods. RESULTS: Disseminated tumour cells were detected in 41 (17%) and 28 (12%) of the 235 examined BM samples by immunomagnetic selection and immunocytochemistry, respectively, with only five samples being positive with both methods. The presence of DTC was associated with adverse outcome (metastasis-free, disease-specific and overall survival) in univariate and multivariate analyses. CONCLUSION: The presence of DTC was associated with adverse prognosis in this cohort of patients curatively resected for CRC, suggesting that DTC detection still holds promise as a biomarker in CRC.

Salvage surgery for locally recurrent rectal cancer: total mesorectal excision during the primary operation does not influence the outcome.

AIM: This study investigated whether total mesorectal excision (TME), when carried out at the original operation for rectal cancer, influenced the effectiveness of subsequent salvage treatment for pelvic recurrence. METHOD: Between September 1990 and January 2006, 124 patients underwent radiotherapy and salvage surgery at the Norwegian Radium Hospital for locally recurrent rectal cancer without known distant metastases. Most of the primary operations had been performed at other hospitals: 62 patients had undergone a non-TME procedure (most operations in this group of patients were carried out before 1994); and 62 patients had undergone a TME procedure (all operations in this group of patients were carried out after 1992). In the TME group, 17 patients also received radiosensitizing chemotherapy. RESULTS: A lower proportion of primary abdominoperineal resection and more sensitizing chemotherapy seemed to be to the advantage of the TME group, while a higher frequency of intra-operative radiotherapy might be beneficial in the non-TME group. The 5-year survival and R0 stage achievement were 30/24% and 44/40% for non-TME/TME groups. The local re-recurrence rates were nearly identical, at around 50%, for both groups. There was no change in R stage over time. CONCLUSION: A primary operation which includes TME does not reduce the effectiveness of subsequent salvage treatment for locally recurrent rectal cancer.

[Postoperative wound infections in elective colorectal surgery]. / Postoperative sårinfeksjoner ved elektiv kolorektalkirurgi.

BACKGROUND: Surgical wound infections still represent a significant problem in colorectal surgery. We wanted to investigate the frequency of postoperative wound infections in patients who had elective colorectal surgery at Lillehammer County Hospital. By reviewing relevant literature we also wanted to assess the evidence base for using antimicrobial prophylaxis in colorectal surgery, which regimens are to be preferred, and the probable reduction in wound infections. MATERIAL AND METHODS: 99 patients were followed up at 14 days after surgery; presence or absence of wound infection was noted. Samples for culture were obtained in all patients with suspected wound infection. Literature on the subject was studied focusing on systematic reviews. RESULTS: Eight out of 99 patients (8%) had wound infections. In a systematic review of 147 studies comparing different antibiotic regimens, the overall infection rate for patients receiving antibiotic prophylaxis was 11%. INTERPRETATION: The surgical wound infection rate was comparable with the results from relevant systematic reviews. The effect of antimicrobial prophylaxis is well documented. A combination of an anaerobic and an aerobic drug should be used, but no gold standard can be identified. Two adequate regimens have been investigated in controlled studies carried out in Norway.