GECOP-MMC: phase IV randomized clinical trial to evaluate the efficacy of hyperthermic intraperitoneal chemotherapy (HIPEC) with mytomicin-C after complete surgical cytoreduction in patients with colon cancer peritoneal metastases

BACKGROUND

The French PRODIGE 7 trial, published on January 2021, has raised doubts about the specific survival benefit provided by HIPEC with oxaliplatin 460 mg/m² (30 minutes) for the treatment of peritoneal metastases from colorectal cancer. However, several methodological flaws have been identified in PRODIGE 7, specially the HIPEC protocol or the choice of overall survival as the main endpoint, so its results have not been assumed as definitive, emphasizing the need for further research on HIPEC. It seems that the HIPEC protocol with high-dose mytomicin-C (35 mg/m²) is the preferred regime to evaluate in future clinical studies.

METHODS

GECOP-MMC is a prospective, open-label, randomized, multicenter phase IV clinical trial that aims to evaluate the effectiveness of HIPEC with high-dose mytomicin-C in preventing the development of peritoneal recurrence in patients with limited peritoneal metastasis from colon cancer (not rectal), after complete surgical cytoreduction. This study will be performed in 31 Spanish HIPEC centres, starting in March 2022. Additional international recruiting centres are under consideration. Two hundred sixteen patients with PCI ≤ 20, in which complete cytoreduction (CCS 0) has been obtained, will be randomized intraoperatively to arm 1 (with HIPEC) or arm 2 (without HIPEC). We will stratified randomization by surgical PCI (1-10; 11-15; 16-20). Patients in both arms will be treated with personalized systemic chemotherapy. Primary endpoint is peritoneal recurrence-free survival at 3 years. An ancillary study will evaluate the correlation between surgical and pathological PCI, comparing their respective prognostic values.

DISCUSSION

HIPEC with high-dose mytomicin-C, in patients with limited (PCI ≤ 20) and completely resected (CCS 0) peritoneal metastases, is assumed to reduce the expected risk of peritoneal recurrence from 50 to 30% at 3 years.

TRIAL REGISTRATION

EudraCT number: 2019-004679-37; Clinicaltrials.gov: NCT05250648 (registration date 02/22/2022, ).

Band selection in spectral imaging for non-invasive melanoma diagnosis

A method consisting of the combination of the Synthetic Minority Over-Sampling TEchnique (SMOTE) and the Sequential Forward Floating Selection (SFFS) technique is used to do band selection in a highly imbalanced, small size, two-class multispectral dataset of melanoma and non-melanoma lesions. The aim is to improve classification rate and help to identify those spectral bands that have a more important role in melanoma detection. All the processing steps were designed taking into account the low number of samples in the dataset, situation that is quite common in medical cases. The training/test sets are built using a Leave-One-Out strategy. SMOTE is applied in order to deal with the imbalance problem, together with the Qualified Majority Voting scheme (QMV). Support Vector Machines (SVM) is the classification method applied over each balanced set. Results indicate that all melanoma lesions are correctly classified, using a low number of bands, reaching 100% sensitivity and 72% specificity when considering nine (out of a total of 55) spectral bands.

Malignant melanoma arising from a perianal fistula and harbouring a BRAF gene mutation: a case report

Background

Melanoma of the anal region is a very uncommon disease, accounting for only 0.2-0.3% of all melanoma cases. Mutations of the BRAF gene are usually absent in melanomas occurring in this region as well as in other sun-protected regions. The development of a tumour in a longstanding perianal fistula is also extremely rare. More frequent is the case of a tumour presenting as a fistula, that is, the fistula being a consequence of the cancerous process, although we have found only two cases of fistula-generating melanomas reported in the literature.

Case Presentation

Here we report the case of a 38-year-old male who presented with a perianal fistula of four years of evolution. Histopathological examination of the fistulous tract confirmed the presence of malignant melanoma. Due to the small size and the central location of the melanoma inside the fistulous tract, we believe the melanoma reported here developed in the epithelium of the fistula once the latter was already formed. Resected sentinel lymph nodes were negative and the patient, after going through a wide local excision, remains disease-free nine years after diagnosis. DNA obtained from melanoma tissue was analysed by automated direct sequencing and the V600E (T1799A) mutation was detected in exon 15 of the BRAF gene.

Conclusion

Since fistulae experience persistent inflammation, the fact that this melanoma harbours a BRAF mutation strengthens the view that oxidative stress caused by inflammatory processes plays an important role in the genesis of BRAF gene mutations.

Trocar site hernia after laparoscopic ventral hernia repair

BACKGROUND

The incidence of trocar site hernia (TSH) after laparoscopic ventral hernia repair (LVHR) is reported to be low. The present study investigates the associated risk factors, with a view to preventing this complication.

METHODS

A retrospective study was made of the incidence of TSH in a personal series of LVHR, recording anthropometric and clinical data on the patients. Risk factors were assessed by bivariate and multivariate analyses. The patients were subjected to clinical and telephone follow-up.

RESULTS

In a series of 27 LVHR, the incidence of TSH was 22% (6 patients). The use of meshes larger than 10 x 15 cm for LVHR was the only TSH risk factor to reach statistical significance. Female gender and diabetes showed a higher incidence in the TSH group.

CONCLUSIONS

The use of large meshes may be a risk factor for TSH. We believe this to be due to dilatation of the trocar orifice during introduction of the mesh, and also to postoperative retraction of the mesh.

Efficacy of PdB in preventing intraoperative risk of infectious diseases

The objectives of this study were to (1) determine the number of punctures surgeons and assistants suffer during operations involving a laparotomy during the intraabdominal and closure phases; and (2) determine if the number of puncture injuries during wound closure can be reduced using a new surgical instrument (PdB) that protects the surgeon's hands and the patient's viscera against needlesticks. For the first objective, all laparotomies performed during 1 month (n = 52) were controlled, collecting the gloves used and determining the number of perforations. For the second objective, a randomized prospective controlled study, involving two series of 100 medial laparotomies, was carried out. The incidence of perforations was 29% during the intraabdominal phase and 16% during the wound closure phase. The glove perforation rate while closing medial laparotomies was 31.5% if the PdB was not used and 3% if the PdB was used (p < 0.0001). The glove perforation rate during laparotomy is significant, but with the use of the PdB this incidence can be significantly reduced.