Liver tumors, albeit arising from diverse origins, are all the result of an uncontrolled growth of abnormal liver cells (primary tumors) or of cells arriving from other sites (secondary tumors or metastases). These tumors, if left untreated, lead to liver malfunction.
The liver, looking uniform and compact from the outside, is in fact an extremely complex organ – from the functional, the metabolic (being the real chemical laboratory of our bodies) and the anatomical points of view (having three vascular networks and a route for the outflow of bile, all intersecting each other inside of the organ).
The two main tumors, arising and growing in the liver, are hepatocarcinoma and cholangiocarcinoma. There can also be metastatic tumors affecting the organ, spreading from other locations: most frequently, from the colon.
Surgery plays a central role in the treatment of liver tumors, generally constituting an essential element in curative therapeutic plans. The success of liver surgery lies in the crucial balance between removing the tumor, while leaving the organ properly functional. Pr. Guido Torzilli, Head of the Humanitas General Surgery department and the Division of Hepatobiliary surgery, and his team developed several innovative surgical techniques allowing the extended liver conservation.
The revolution of traditional surgery
Liver has a precious peculiarity of self-regenerating. If part of it is removed, the remaining portion will get bigger. To clarify, the removed part does not reform, just as amputated vessels are not reconstituted, but the remaining part of the liver inflates. However, if an excessively large portion has been removed, the residual liver fails to guarantee the correct functioning of the organ, despite its’ swelling, leading to hepatic insufficiency. This, naturally, constitutes a crucial limitation to the possibility of operating a patient with liver cancer, as the surgeons strive to remove the tumor, while conserving as much of the organ as possible.
A surgeon performing traditional surgery has few options of avoiding getting lost in the anatomical complexity of the organ. For this reason, the specialists remove not only the portion of the liver occupied by the tumor, but also a large part of healthy tissue. In complex cases, where it is particularly crucial to conserve as much of the liver as possible, the surgery is performed in two phases: the first on the left portion and the second the right portion of the organ.
Professor Torzilli and his team at Humanitas were the first in the world to discover a new way of operating patients with liver cancer, maximizing the conservation of healthy tissue, while removing the compromised one, thus excising otherwise inoperable tumors. A radical, yet safe approach, this technique protects the patient further from the risk of postoperative liver failure and can be used for otherwise inoperable tumors.
“Our expertise continually reevaluates the criteria of operability, reclassifying the very concept of hepatic resection (i.e. the partial removal of the organ). The latest development in liver surgery is detachment surgery, an approach based on ultrasound guidance, building on the principle of detaching the tumor from intrahepatic blood vessels and exploiting the liver’s adaptation to the tumor,” explains Pr. Torzilli.
The development of detachment surgery
One of Pr. Torzilli and his team’s main research areas concerns tumors close to the large intrahepatic vessels. The removal of these tumors requires the sacrifice of the vessel in contact with it and, hence, of the tissue that depends on that vessel for the inflow or outflow of blood. “After twenty years of clinical research we have shown that it is possible to separate a tumor adjacent to a large intrahepatic vessel without exposing the patient to a greater risk of tumor recurrence, compared to the alternative of removing the vessel and all the tissue dependent on it. This approach, allowing the removal of deep tumors and in contact with the large vessels without sacrificing healthy tissue, has opened new horizons in liver surgery, offering surgical treatment to otherwise inoperable patients,” continues the Doctor.
Adaptation of the liver to the tumor
However, the detachment of the tumor from the intrahepatic vessels is not always possible. When this happens, and the vein carrying the blood out of the liver, for the latter to enter the heart after only a few centimeters, is affected, the liver itself rectifies the issue. How does it do it? In 2010 Professor Torzilli and his team, demonstrated for the first time in the world that in these cases the liver opens internal by-passes that divert blood from one vein to the adjacent one, allowing the tissue to function even when the vein, affected by a tumor, is closed. These by-passes, identified and mapped with ultrasound, enabled the Humanitas team to introduce new types of interventions that involve sacrificing the veins infiltrated by the disease without removing healthy tissue.
Removing tumors in the center of the liver with liver tunneling
Thanks to the concepts of detachment surgery and natural by-passing, Pr. Torzilli and his Humanitas team have developed numerous surgery techniques, publishing their findings in the most prestigious scientific journals in the field over the years. The last such technique has been liver tunneling, described for the first time in Annals of Surgical Oncology in 2014, with Annals of Surgery reporting the experience of the first twenty patients in early 2019.
“Liver tunneling allows the removal of tumors that have grown in the center of the liver and that are imprisoned by the blood vessels that carry blood inside and outside the organ. By creating a real tunnel that crosses the liver from top to bottom, it is possible to remove the tumor leaving the organ almost intact and perfectly functional: it is a highly complex but safe procedure that allows us to remove tumors that would otherwise require extensive demolition or would be inoperable,” continues Pr. Torzilli.
The leader in in scientific research and clinical practice
Professor Guido Torzilli and his team have revolutionized liver surgery in terms of techniques and paradigms. Over the years, the team has achieved impressive goals in small steps and through the scrutiny of the international scientific community, which has then verified the validity of these achievements, allowing their dissemination in the most prominent scientific journals.
“For twenty years, we have been translating our research work into daily clinical practice, striving to offer better care to our patients,” explains Professor Torzilli. This work has positioned the Humanitas team among the leading groups in global liver surgery, where it occupies a place of particular importance thanks to the originality of its innovative proposals.
“Beyond technology, there is dedication, sacrifice, rigor and profound insights. Ultrasound is the mother of our discoveries, helping identify the most critical points and find innovative solutions that we use in clinical practice today. I cannot forget that I learned using ultrasound in the operating room from my Japanese teacher, who, I can say, truly formed me as a surgeon. Thanks to him, to ultrasound, and to these last twenty years of great commitment, my group and I can now carry out interventions that would otherwise be unthinkable: sophisticated, less demolishing, and safer surgeries. We can say that we try to remove less (of the healthy liver) to remove more (of the tumor, the disease),” concludes Pr. Torzilli.