Prognostic value of specific KRAS mutations in patients with colorectal peritoneal metastases

BACKGROUND

There is little evidence on KRAS mutational profiles in colorectal cancer (CRC) peritoneal metastases (PM). This study aims to determine the prevalence of specific KRAS mutations and their prognostic value in a homogeneous cohort of patients with isolated CRC PM treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

MATERIALS AND METHODS

Data were collected from 13 Italian centers, gathered in a collaborative group of the Italian Society of Surgical Oncology. KRAS mutation subtypes have been correlated with clinical and pathological characteristics and survival [overall survival (OS), local (peritoneal) disease-free survival (LDFS) and disease-free survival (DFS)].

RESULTS

KRAS mutations occurred in 172 patients (47.5%) out of the 362 analyzed. Two different prognostic groups of KRAS mutation subtypes were identified: KRASMUT1 (G12R, G13A, G13C, G13V, Q61H, K117N, A146V), median OS > 120 months and KRASMUT2 (G12A, G12C, G12D, G12S, G12V, G13D, A59E, A59V, A146T), OS: 31.2 months. KRASMUT2 mutations mainly occurred in the P-loop region (P < 0.001) with decreased guanosine triphosphate (GTP) hydrolysis activity (P < 0.001) and were more frequently related to size (P < 0.001) and polarity change (P < 0.001) of the substituted amino acid (AA). When KRASMUT1 and KRASMUT2 were combined with other known prognostic factors (peritoneal cancer index, completeness of cytoreduction score, grading, signet ring cell, N status) in multivariate analysis, KRASMUT1 showed a similar survival rate to KRASWT patients, whereas KRASMUT2 was independently associated with poorer prognosis (hazard ratios: OS 2.1, P < 0.001; DFS 1.9, P < 0.001; LDFS 2.5, P < 0.0001).

CONCLUSIONS

In patients with CRC PM, different KRAS mutation subgroups can be determined according to specific codon substitution, with some mutations (KRASMUT1) that could have a similar prognosis to wild-type patients. These findings should be further investigated in larger series.

Is Systemic Chemotherapy Useful in Patients Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Colorectal Peritoneal Metastases? A Propensity-Score Analysis

PURPOSE

Multimodal treatment of colorectal (CRC) peritoneal metastases (PM) includes systemic chemotherapy (SC) and surgical cytoreduction (CRS), eventually with hyperthermic intraperitoneal chemotherapy (HIPEC), in select patients. Considering lack of clear guidelines, this study was designed to analyze the role of chemotherapy and its timing in patients treated with CRS-HIPEC.

METHODS

Data from 13 Italian centers with PM expertise were collected by a collaborative group of the Italian Society of Surgical Oncology (SICO). Clinicopathological variables, SC use, and timing of administration were correlated with overall survival (OS), disease-free survival (DFS), and local (peritoneal) DFS (LDFS) after propensity-score (PS) weighting to reduce confounding factors.

RESULTS

A total of 367 patients treated with CRS-HIPEC were included in the propensity-score weighting. Of the total patients, 19.9% did not receive chemotherapy within 6 months of surgery, 32.4% received chemotherapy before surgery (pregroup), 28.9% after (post), and 18.8% received both pre- and post-CRS-HIPEC treatment (peri). SC was preferentially administered to younger (p = 0.02) and node-positive (p = 0.010) patients. Preoperative SC is associated with increased rate of major complications (26.9 vs. 11.3%, p = 0.0009). After PS weighting, there were no differences in OS, DFS, or LDFS (p = 0.56, 0.50, and 0.17) between chemotherapy-treated and untreated patients. Considering SC timing, the post CRS-HIPEC group had a longer DFS and LDFS than the pre-group (median DFS 15.4 vs. 9.8 m, p = 0.003; median LDFS 26.3 vs. 15.8 m, p = 0.026).

CONCLUSIONS

In patients with CRC-PM treated with CRS-HIPEC, systemic chemotherapy was not associated with overall survival benefit. The adjuvant schedule was related to prolonged disease-free intervals. Additional, randomized studies are required to clarify the role and timing of systemic chemotherapy in this patient subset.

External validation of COMPASS and BIOSCOPE prognostic scores in colorectal peritoneal metastases treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC)

INTRODUCTION

The selection of patients undergoing cytoreductive- surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is crucial. BIOSCOPE and COMPASS are prognostic scores designed to stratify survival into four classes according to clinical and pathological features. The purpose of this study is to analyze the prognostic role of these scores using a large cohort of patients as an external reference.

METHODS

Overall survival analysis was performed using Log-Rank and Kaplan-Meier curves for each score. The probability of survival at 12, 36, and 60 months was tested using receiver operating characteristic (ROC) curves to determine sensitivity and specificity.

RESULTS

From the validation cohort of 437 patients, the analysis included 410 patients in the COMPASS group and 364 patients in the BIOSCOPE group (100% data completeness). We observed a different patient distribution between classes (high-risk for BIOSCOPE compared to COMPASS, p = 0.0001). Nevertheless, both COMPASS and BIOSCOPE effectively stratified overall survival (Log-Rank, p = 0.0001 in both cases), with a lack of discrimination between COMPASS classes II and III (p = n.s.). COMPASS at 12 m and BIOSCOPE at 60 m showed the best performance in terms of survival prediction (AUC of 0.82 and 0.81). The specificity of the two tests is good (median 81.3%), whereas sensibility is quite low (median 64.2%).

CONCLUSION

Following external validation in a large population of patients with CRC-PM who are eligible for surgery, the COMPASS and BIOSCOPE scores exhibit high inter-test variability but effectively stratify cancer-related mortality risk. While the quality of the scores is similar, BIOSCOPE shows better inter-tier differentiation, suggesting that tumor molecular classification could improve test discrimination capability. More powerful stratification scores with the inclusion of novel predictors are needed.

Enhanced Recovery after Surgery (ERAS) Program for Patients with Peritoneal Surface Malignancies Undergoing Cytoreductive Surgery with or without HIPEC: A Systematic Review and a Meta-Analysis

Enhanced recovery after surgery (ERAS) program refers to a multimodal intervention to reduce the length of stay and postoperative complications; it has been effective in different kinds of major surgery including colorectal, gynaecologic and gastric cancer surgery. Its impact in terms of safety and efficacy in the treatment of peritoneal surface malignancies is still unclear. A systematic review and a meta-analysis were conducted to evaluate the effect of ERAS after cytoreductive surgery with or without HIPEC for peritoneal metastases. MEDLINE, PubMed, EMBASE, Google Scholar and Cochrane Database were searched from January 2010 and December 2021. Single and double-cohort studies about ERAS application in the treatment of peritoneal cancer were considered. Outcomes included the postoperative length of stay (LOS), postoperative morbidity and mortality rates and the early readmission rate. Twenty-four studies involving 5131 patients were considered, 7 about ERAS in cytoreductive surgery (CRS) + HIPEC and 17 about cytoreductive alone; the case histories of two Italian referral centers in the management of peritoneal cancer were included. ERAS adoption reduced the LOS (-3.17, 95% CrI -4.68 to -1.69 in CRS + HIPEC and -1.65, 95% CrI -2.32 to -1.06 in CRS alone in the meta-analysis including 6 and 17 studies respectively. Non negligible lower postoperative morbidity was also in the meta-analysis including the case histories of two Italian referral centers. Implementation of an ERAS protocol may reduce LOS, postoperative complications after CRS with or without HIPEC compared to conventional recovery.

Laparoscopic Cytoreduction Combined with Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Peritoneal Surface Malignancies (PSM): Italian PSM Oncoteam Evidence and Literature Review

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has gained increasing acceptance in clinical practice. Performing CRS and HIPEC laparoscopically represents a challenging and intriguing technical evolution. However, the experiences are limited, and the evidence is low. This retrospective analysis was performed on patients treated with laparoscopic CRS-HIPEC within the Italian Peritoneal Surface Malignancies Oncoteam. Clinical, perioperative, and follow-up data were extracted and collected on prospectively maintained databases. We added a systematic review according to the PRISMA method for English-language articles through April 2022 using the keywords laparoscopic, hyperthermic, HIPEC, and chemotherapy. From 2016 to 2022, fourteen patients were treated with Lap-CRS-HIPEC with curative intent within the Italian centers. No conversion to open was observed. The median duration of surgery was 487.5 min. The median Peritoneal Cancer Index (PCI) was 3, and complete cytoreduction was achieved in all patients. Two patients (14.3%) had major postoperative complications, one requiring reintervention. After a median follow-up of 16.9 months, eleven patients were alive without disease (78.6%), two patients developed recurrence (14.3%), and one patient died for unrelated causes (7.1%). The literature review confirmed these results. In conclusion, current evidence shows that Lap-CRS-HIPEC is feasible, safe, and associated with a favorable outcome in selected patients. An accurate patient selection will continue to be paramount in choosing this treatment.

Radiological assessment of peritoneal carcinomatosis: a primer for resident

The imaging has critical responsibility in the assessment of peritoneal lesions along with estimating the overall extent. Valuing disease burden is crucial for selection of combining cytoreductive surgery (CRS) and intraperitoneal hyperthermic chemotherapy (HIPEC) treatment. An approach that combines the strength of several imaging tools and increases diagnostic accuracy, should be chosen, even if the preferred imaging tool in patients with suspected Peritoneal Carcinomatosis (PC) is CT. The outcomes of PC are mainly correlated to tumor spread, localization, and lesion size. Accurate assessment of these features is critical for prognosis and treatment planning. These data can be evaluated by Peritoneal Cancer Index (PCI), a quantitative index suggested by Harman and Sugarbaker. Additionally, precise predictive biomarkers should be established to predict PC in patients at risk. The radiomics analysis could predict PC throughout the evaluation of cancers heterogeneity.

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.

Organ Sparing for Locally Advanced Rectal Cancer after Neoadjuvant Treatment Followed by Electrochemotherapy

Simple Summary

This is a Phase II randomized controlled trial conducted with the aim of investigating whether the use of Electrochemotherapy after neoadjuvant therapy (ECT) and before surgery in patients with major clinical response allows for a more conservative surgical approach in patients with Locally Advanced Rectal Cancer (LARC) in comparison with the control group that will not receive ECT. The treatment response, in both the control arm and in the treatment arm, will be assessed using the histopathological tumor regression grade on tissue specimens after local excision.

Abstract

Background: Currently, 45–55% of rectal cancer patients receive preoperative chemo- radio-therapy for Locally Advanced Rectal Cancer (LARC). The idea of our study is to use Electrochemotherapy (ECT) before surgery, in patients with major clinical response after neoadjuvant therapy, to allow for a more conservative surgical approach. Objective: To evaluate the increase of the complete response rate after neoadjuvant treatment in LARC and to spare organ function due to total mesorectal excision (TME). Patients and Methods: This is a Phase II randomized controlled trial enrolling 70 patients that will be developed in two stages. In the first step, 28 patients will be enrolled: 14 of these will receive ECT for four weeks after neo-adjuvant treatment and then local excision (treatment group) and 14 patients will receive neo-adjuvant treatment and then local excision (control group). If an increase of response rate is observed in the first stage, and/or feasibility/safety is demonstrated, the second stage of the trial will be performed, enrolling an additional 42 patients. The treatment response. in both the control arm and the treatment arm, will be assessed using the histopathological tumor regression grade on tissue specimens after local excision.

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.

Polymorphism of the mitochondrial DNA control region in Italians

Mitochondrial DNA sequences of the hypervariable regions HVI and HVII were analysed in 83 Caucasians living in central Italy to expand the database for forensic identification purposes, and 75 different haplotypes resulting from 62 polymorphic positions in HVI and 44 in HVII were observed. The most frequent haplotype (263G, 309.1C, 315.1C) was shared by 7 individuals, 2 haplotypes were shared by 2 individuals, and 72 were unique. The genetic diversity was found to be 0.99 and the random match probability 1.9%. A condition of sequence heteroplasmy was found in only one case at nt 16311, whereas a length heteroplasmy was found in the homopolymeric stretch of cytosines 303-315. Our results indicate that in direct sequencing beyond the poly-cytosine stretch, the overlap is due to length heteroplasmy, whereas the blurred signal occurs when the stretch is composed of more than 10 cytosines.

Allele typing of short tandem repeats by capillary electrophoresis

Capillary electrophoresis with laser-induced fluorescence was applied to the analysis of six STRs and the amelogenin sex test with the purpose of verifying accuracy and precision of the sizing method with the GS500 internal standard. Sequenced dye-labeled, PCR-amplified alleles from amelogenin, HumVWA31, HumTH01, HumF13A01, HumFIBRA, D21S11 and HumCSF1PO loci were run several times on the same capillary and on multiple capillaries and the offset of computer-measured fragment sizes from the expected molecular weights was calculated and analysed. All loci except D21S11 showed a poor degree of accuracy. Precision results from run-to-run and day-to-day injections displayed a maximum standard deviation (SD) > 0.15 nt for HumVWA31, HumF13A01, D21S11 and HumFIBRA, although the maximum range of calculated sizes in multiple runs was lower than 1 basepair. No variation in precision was observed according to the quality of the DNA template. Allele typing by comparison with allelic ladders for each locus is recommended.

Polymorphism and sequence variations of the HumCD4 pentameric microsatellite in an Italian population sample

A sample of 265 subjects from central Italy was analyzed at the HumCD4 locus by polymerase-chain-reaction (PCR). Phenotypes were identified by comparison with a sequenced ladder, after high-resolution horizontal polyacrylamide gel electrophoresis (PAGE) followed by silver staining. A set of representative alleles was sequenced by Taq-cycle-sequencing with dye terminator labeling and capillary gel electrophoresis strategies. Eight common alleles--5, 6, 7, 8, 9, 10, 11, 12--and a rare larger 14, never before described in Caucasians, were found. Allele and genotype frequencies were similar to those described in former studies on Caucasians, with a prevalency of alleles number 5, 6, 10. Sequence analysis showed that the polymorphism is due to a pentameric TTTTC basic motif, tandemly repeated, and that from allele number 10 onwards the fourth repeat presents a T to C translation (CTTTC). Instead, allele number 9 may exist in two forms, because 75% of alleles examined in this study presented the CTTTC motif at the fourth position, while the remaining 25% had the basic repeat structure.

Polymerase chain reaction typing of D21S11 short tandem repeat polymorphism by capillary electrophoresis. Allele frequencies and sequencing data in a population sample from central Italy

Blood samples were collected from 100 individuals living in Central Italy and analysed for STR locus D21S11 by capillary electrophoresis on an ABI Prism 310 genetic analyzer. For fragment sizing, PCR amplification products, obtained using a 6-FAM 5'-labeled reverse primer and an unlabeled forward primer, were run with an internal size standard labeled with TAMRA dye and typed using the local reciprocal method. An allele ladder consisting of a mix of sequenced amplified products was also prepared. An Italian population database was established. No deviation from Hardy-Weinberg equilibrium was observed. The result of statistical analysis were highly informative (PD = 0.94; mean exclusion change = 0.66). DNA sequencing was performed on a set of representative alleles by Taq cycle sequencing using dye terminator labeling chemistry. A new structural variant was found.

PCR analysis of the STR HUMF13A01 in a population sample of central Italy

A population genetic study was carried out on an Italian sample of Central Italy (n = 159) using the short tandem repeat (STR) system HUMF13A01. After vertical electrophoresis in denaturing polyacrylamide gel, 11 alleles were found. No deviation from the Hardy-Weinberg equilibrium were observed. The power of discrimination (PD) was 0.91 and the chance of exclusion was 0.59. The allelic comparison with previous Italian population studies showed no significant difference.

Sexual function after resection for rectal cancer

Major rectal operation, that is, abdominoperineal or anterior resection, for cancer frequently damages the autonomic pelvic nerve supply with resultant sexual dysfunction. The anatomic characteristics and function of the autonomic nervous system in the pelvis has been reviewed. Sexual function after rectal excision for cancer was studied in 25 male patients who were less than 60 years of age and exhibited normal sexual activity preoperatively. Of nine patients who had abdominoperineal resection, four were impotent and two reported no ejaculation with normal potency postoperatively. Of 4 patients who had high anterior resection, only 1 reported no ejaculation, whereas of 12 patients with low anterior resection, 4 were impotent and 3 reported no ejaculation. A higher incidence of sexual dysfunction was noted after abdominoperineal resection compared with after anterior resection (66 percent and 50 percent, respectively). However, the incidence after low and very low anterior resection was comparable with that after abdominoperineal resection (58 percent and 66 percent, respectively). Advanced patient age and very low resection were the two main factors effecting sexual dysfunction after major rectal operation. Although we believe that careful operative technique might reduce the incidence of sexual disturbances attributable to sympathetic fiber damage, avoidance of parasympathetic damage during operation cannot be accomplished because the most likely site of injury, namely the periprostatic plexus, is usually within the operative field, the exception being cases in which the tumor is small, thus allowing preservation of the rectoprostatic fascia.

A study of the pathology of the crush syndrome

Subsequent to the earthquake which occurred in Southern Italy in November 1980, 19 patients were admitted to the University of Naples--II Medical School with crush syndrome. Clinical and biochemical studies were carried out in eight of them. The most interesting observation was the inconstant relation between the type of lesion and the clinical course, leading to the assumption of two diverse physiopathologic mechanisms--one for crush and the other for compression. The timely recognition of the two syndromes is difficult; an elevated creatine-creatinine ratio has been found in those patients with an irreversible crush syndrome. We believe this to be the only element which would permit a prompt distinction between the two pathologic states and which would provide an indication for early, life-saving amputation.