Η τεχνική της μη αναστρέψιμης ηλεκτροπόρωσης (IRE) περιλαμβάνει ουσιαστικά την έκλυση εκατομμυρίων ηλεκτρικών παλμών ανά δευτερόλεπτο, οι οποίοι σκοτώνουν τα καρκινικά κύτταρα προστατεύοντας τον διπλανό ιστό.

Όπως εξηγεί ο Κωνσταντίνος Σοφοκλέους, επεμβατικός ακτινολόγος στο Memorial Sloan-Kettering Cancer Center της Νέας Υόρκης, η μέθοδος αυτή είναι αρκετά χρήσιμη για τη θεραπεία του καρκίνου του ήπατος, του πνεύμονα, του παγκρέατος και άλλων οργάνων παρακείμενων σε αιμοφόρα αγγεία, νεύρα και άλλες ευαίσθητες δομές.

Η θεραπευτική αντιμετώπιση τύπων καρκίνου που βρίσκονται κοντά σε ευαίσθητες περιοχές περιλαμβάνει συνήθως χειρουργείο και την εφαρμογή της μεθόδου της θερμικής νέκρωσης, η οποία αρχικά θερμαίνει και στη συνέχεια παγώνει τον όγκο.

Αυτή όμως μπορεί να βλάψει τον υγιή ιστό, αποτελώντας παράλληλα κίνδυνο για τις περιβάλλουσες δομές.

Με την IRE πραγματοποιείται μια μικροσκοπική τομή στο μέγεθος της μύτης ενός μολυβιού για την είσοδο στον οργανισμό του μικροσκοπικού οργάνου που θα στοχεύσει στον όγκο.

Μέσω αυτού περνούν ισχυρά ηλεκτρικά πεδία που δημιουργούν μικρές τρύπες στις μεμβράνες των κυτταρικών όγκων.

Η διαδικασία αυτή τα σκοτώνει, καθώς διαταράσσει τη μοριακή ισορροπία στο εσωτερικό και το εξωτερικό των κυττάρων.

Στην έρευνα που πραγματοποίησε ο Σοφοκλέους συμμετείχαν είκοσι πέντε ασθενείς με καρκίνο που είχε κάνει μεταστάσεις σε διάφορα σημεία του σώματός τους και έφεραν όγκους μέσου μεγέθους 2 εκατοστών.

Ύστερα από τριάντα θεραπευτικές συνεδρίες η μέθοδος IRE αποδείχτηκε αρκετά ασφαλής για περαιτέρω διερεύνηση σε μεγαλύτερης κλίμακας κλινικές δοκιμές.

«Η θεραπεία φαίνεται να είναι αρκετά ωφέλιμη για ανθρώπους με καρκίνο που έχει κάνει μετάσταση και για τους οποίους δεν υπάρχουν καλές θεραπευτικές επιλογές» δήλωσε ο Έλληνας επιστήμονας κατά την παρουσίαση των αποτελεσμάτων της έρευνάς του στο 38ο επιστημονικό συνέδριο της Διεθνούς Ενωσης Ακτινολογίας στη Νέα Ορλεάνη.

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Αλεξάνδρα Χυδηριώτη

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http://www.medicalnewstoday.com/releases/259132.php

Irreversible Electroporation Kills Hard-To-Treat Tumors At The Cellular Level

Main Category: Cancer / Oncology    Article Date: 17 Apr 2013 - 0:00 PDT

A new, minimally invasive treatment that tears microscopic holes in tumors without harming healthy tissue is a promising treatment for challenging cancers, suggests a preliminary study presented at the Society of Interventional Radiology's 38th Annual Scientific Meeting in New Orleans.

"Irreversible electroporation (or IRE) is a new way to attack cancer, using microsecond electrical pulses to kill cancer at the cellular level without damaging healthy tissue nearby. It may be especially beneficial in treating liver, lung, pancreatic and other cancers that are close to blood vessels, nerves and other sensitive structures," said Constantinos T. Sofocleous, M.D., Ph.D., FSIR, lead author and interventional radiologist at Memorial Sloan-Kettering Cancer Center in New York, N.Y. "IRE appears to be especially beneficial in people with cancer that has spread beyond the primary tumor who do not have good treatment options," he added. "IRE uses strong electric fields to create tiny holes in the cell membrane, killing the cancer by disrupting the balance between the molecules inside and outside the cell - without resulting in other cell damage. This makes IRE potentially ideal for treating tumors close to sensitive structures," said Sofocleous.

Whereas other treatments - such as surgery, or heating and freezing (also known as thermal ablation) - can damage healthy tissue near the tumor, IRE precisely perforates the cancer cells, posing fewer risks to major blood vessels, nerves, bile ducts and other vital structures, he said.

IRE has been shown to be safe in the treatment of cancers that have metastasized, or spread, to the liver, lung, bladder and the pelvic region. In this study, 25 participants with a total of 40 metastases to the liver from lung, pancreas, thyroid gland, prostate, uterus and uterine lining, ovaries and rectum primaries, were treated with IRE. The average size of the tumors was about two centimeters. IRE was used due to the location of the lesions, near critical structures that would be affected by thermal ablation. Researchers completed all 30 treatment sessions with no major complications, showing IRE to be safe enough for further investigation and expansion of its use to large clinical trials.

IRE is on the frontier of interventional radiology treatments that are nonsurgical and involve minimal risk and downtime for cancer patients. Interventional radiologist treatments involve making incisions the size of a pencil tip and use medical imaging to guide tiny instruments to the targeted tumors.

"Using the least-invasive treatments available, interventional radiologists are able to destroy entire tumors with a needle and image guidance," said Sofocleous. "We often treat patients who have no other conventional treatment options or have such poor health that even minimally invasive surgery is too dangerous. Researchers are working to increase the effectiveness of IRE and eventually will test it against other treatments for these tumors, including radiofrequency ablation, microwave ablation and cryoablation," he noted.

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http://www.medicalnewstoday.com/releases/259310.php

When Standard Liver Cancer Treatment Doesn't Work Or Isn't Possible, New Ablation Technique Holds Promise

Main Category: Liver Disease / Hepatitis  Also Included In: Cancer / Oncology  Article Date: 21 Apr 2013 - 0:00 PDT

A new minimally invasive tumor ablation technique is providing hope for liver cancer patients who can't undergo surgery or thermal ablation, a study shows.

The study of 22 patients at the Universitatsklinikum Regensberg in Regensberg, Germany, found that irreversible electroporation (IRE) successfully destroyed tumor tissue in 70% of these patients. These patients were not responsive to conventional therapy or their tumor was in a location that was not suitable for standard treatment, said Dr. Philipp Wiggermann, lead author of the study. "If one considers that IRE was really the only option for these patients, the results are very promising," he said.

There were two major complications in the study, but neither of them was life-threatening, said Dr. Wiggermann. One patient suffered partial thrombosis of the left portal vein. "It is not clear that the IRE procedure caused the partial thrombosis, but since it appeared after the ablation treatment, it was considered as a therapy-associated side effect," he said. There was accidental injury to another patient's gallbladder during the ablation treatment. "Accidental injury to surrounding organs is a risk of all percutaneous ablation techniques. Treatment of liver tumors is especially difficult due to the respiratory movement of the diaphragm leading to continuous shifting of the organ position," said Dr. Wiggermann.

IRE disrupts the cell membrane and results in cell death.

It is currently undergoing clinical investigation for treatment of malignant liver and lung lesions, Dr. Wiggermann said.

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