sprache deutsch  -  sprache englisch  -  sprache russisch  -  sprache arabisch

Benignant Liver Tumours

 

The most common benign liver tumours


lebertumorIn medicine, a fundamental difference is made between primary and secondary tumours (metastases). Primary tumours form in their own cells, for instance in the cells of the liver tissue, and they can be benign or malignant. Metastases form from scattered cells coming from distant tumour focuses (e.g. bowel), which have wandered via the lymphatics into the liver, and they are always malignant. During ultrasound examinations of the liver, benign tumours are found by chance in 9% of the population, and they are discussed in this chapter. The names given to benign tumours of the liver depend on the differing cells of which the liver consists and which then multiply: for instance the liver cell itself (hepatocyte), cells of the bile ducts (cholangio-epithelial cell) or supporting cells (mesenchymal cell).

The liver cell adenoma, a proliferation of the liver cell itself, has to be mentioned as another benign tumour. It is found mainly in women between 20 and 40 years old. In the liver, single adenoma nodes are mostly found, which however may reach a diameter of up to 30 cm and normally are not encapsulated. In adenoma nodes, an accumulation of fats and sugar is found. This tumour goes along with occasional local bleedings and with necrotic liver cells in the nodes, which may cause pains in the upper abdomen (10% of the patients). The risk of bleedings and the risk of degeneration ascribed to the adenoma (first stage of a liver cell carcinoma) are the reasons, why a liver cell adenoma is normally surgically removed. The focal nodular hyperplasia (FNH) is the third disease to be mentioned. It is found in men and women of every age, but more often in women. A connection between the taking of contraceptive hormones and the disease for women is under discussion. Here, all original cells are found in the proliferation of the tissue, contrary to the liver adenoma. In the case of FNH, the liver shows nodal tumour tissue with a scar in the centre of the tumour and star-shaped fibrous cords progressing to the outside. To complete the picture, the cystic tumours of the liver have to be mentioned, which are caused by the tapeworm of the dog or the fox: cystic and alveolar echinococcosis. These diseases are zoonoses, i.e. diseases of the vertebrae (e.g. sheep). They can be transmitted to human beings because, in case of an infection, the latter serve as accidental intermediate hosts in the stage of development of the tapeworm. If there is an infection caused by a dog tapeworm, the liver or the lung of the human being is affected because the ingested larva is transformed into a hydrocyst, which is enclosed in a capsule. The larva of the fox tapeworm, by contrast, permeates the liver with many blisters, which have the size of a hazelnut and destroy or displace the healthy tissue. The liquid in these blisters contains again larvae, which is a great challenge for the surgical and chemotherapeutical therapies as the blisters must not burst in order to avoid an infection.

The Haemangioma

The most common benign tumour is the haemangioma or strawberry mark (fig. 3,4 and 5), which forms through a proliferation of supporting cells of blood vessels. Its size varies between some millimetres and a couple of centimetres. Haemangiomas appear in the liver as well lined, calcified structures and are often enclosed by a thin capsule. They are not liable to degenerate. Also frequent and harmless are the congenital liver cysts, which form from varying cells and are found single or numerous in the liver tissue. They are only removed if their size or location causes complaints.

riesen haemangiom 

haemagiom unten 

Leberzysten

In der Leber können wie in anderen Organen wie der Niere auch Zysten gefunden werden (Abb. 6, 7 und 8)

leberzysten 

leberzyste 

ct leberzystenEine Zyste, weist eine dünne Kapsel auf, die mit einem Endothel (innere Schicht) ausgekleidet ist, welche eine Flüssigkeit absondert. Die Zystenflüssigkeit bläht die Zyste wie einen Ballon auf, was Zysten meistens eine rundliche kugelige Form gibt, die auch im Computertomographen gut zu sehen ist (Abb. 9a und 9b). Zysten werden sehr häufig bei Routineuntersuchungen mit dem Ultraschall gefunden und sind bis zu einer Grösse von sechs bis neun Zentimetern belanglos. Wahrscheinlich sind Zysten angeborene Fehlbildungen, die völlig belanglos sind. Erst wenn sie über neun Zentimeter gross sind, effektiv Schmerzen verursachen oder an Grösse zunehmen, müssen sie operativ behandelt werden. Neben diesen sogenannt simplen Zysten gibt es auch komplizierte Zysten. Sie werden so bezeichnet, weil ihr Inhalt im Ultraschall oder CT nicht klare Flüssigkeit als Inhalt zeigt, sondern Unterteilungen durch Septen, Einblutungen oder weil ihr Inneres einen undefinierbaren Inhalt aufweist (Abb. 9a und 9b). Hier ist die Differenzialdiagnose zu anderen eventuell gefährlicheren Leber Krankheiten wichtig. Einfache Zysten sind aber mit bildgebenden Methoden relativ einfach nachzuweisen.

Eine spezielle, vererbliche Krankheit ist die Zystenleber. Bei dieser Krankheit ist das Lebergewebe diffus von vielen grösseren und kleineren Zysten durchsetzt. Zystenlebern können grotesk gross werden und den Betroffenen meistens mechanische Probleme verursachen mit Schmerzen und Verdauungsproblemen. Diese Krankheit betrifft nicht nur die Leber sondern auch die Nieren, die ebenfalls mit Zysten so stark durchsetzt sind, dass über die Zeit keine genügend grosse Nierenfunktion mehr besteht. Bei Schmerzen, mechanischen Störungen und Verdauungsstörungen können diese Zysten – oft laparoskopisch - verkleinert werden, indem die frei an der Oberfläche liegenden Zystendächer entfernt werden.

Echinokokkus Zysten

Der Vollständigkeit halber müssen die zystischen Tumoren der Leber genannt werden, die durch den Hunde- und Fuchsbandwurm (lateinisch Echinococcus) hervorgerufen werden. Man spricht hier auch von zystischen (E. cysticus) und alveolären (E. alveolaris oder multilocularis) Echinokokkosen. Sie sind in einem CT oft gut sichtbar (Abb. 10, 11 und 12).

zyste fuchsbandwurm 

 lebertumor

Diese Erkrankungen sind Zoonosen, das heisst eigentlich Erkrankungen der Wirbeltiere (z.B. von Schafen), die aber auf den Menschen übertragen werden können, weil dieser bei Infektion als zufälliger Zwischenwirt im Entwicklungskreislauf der Bandwürmer auftritt. Bei der Infektion durch den Hundebandwurm bildet sich in der Leber oder Lunge des Menschen aus der aufgenommenen Larve eine Wasserblase, die von einer Kapsel umschlossen ist. Die Larven des Fuchsbandwurmes durchsetzen dagegen die Leber mit vielen haselnussgrossen Bläschen und zerstören oder verdrängen das gesunde Gewebe. Die Flüssigkeit in diesen Blasen enthält wiederum Larven, was für die chirurgische und chemotherapeutische Therapie eine grosse Herausforderung ist, da diese Blasen nicht platzen dürfen, um eine Ausbreitung der Infektion zu verhindern (Abb. 13 und 14).

operation leberzyste

leberoperation zysteDie Zysten, die durch den E. cysticus gebildet werden, können meistens relativ einfach operativ entfernt werden, in dem ihr Inhalt mit hochprozentiger Kochsalzlösung abgetötet wird. Anschliessend werden die toten Echinokokken (lat. Scolices) abgesaugt. Sehr hilfreich ist der Ulmer Trichter (Abb. 15), durch den abgesaugt wird ohne dass Inhalt der Zyste im Bauchraum verstreut wird.

Der E. alveolaris hingegen wächst praktisch wie ein bösartiger Tumor mit vielen kleineren und grössere Zysten an verschiedenen Orten der Leber aber auch an anderen abdominalen Stellen bildet.

 

 

grosse zyste leberDiese Echinokokken müssen ebenfalls mit einer Operation behandelt werden (Abb. 16, 17, 18, 19, und 20), die sehr schwierig verlaufen kann, da der Parasit in die Gallenwege und Gefässe einwachsen kann und oft nur sehr schwer zu entfernen ist. Beide Parasitenarten können neben den bildgebenden Methoden auch mit mit speziellen Bluttests nachgewiesen werden. Der E. alveolaris muss nicht nur operiert sondern vor und nach einer Operation mit einem speziellen Medikament (Mebendazol) vor- und nach behandelt werden.

 

 

 

zystenblasen

Echinokokkus Zysten 

Gutartige Neubildungen der Leber

 leberzirrhose
Die eigentlichen gutartige Lebertumoren, die sich aus den Leberzellen selbst bilden sind das Leberzelladenom und die Fokale Noduläre Hyperplasie. Eine Veränderung der Leber, die mit knotigem Wachstum einhergeht ist auch die Leberzirrhose (Abb. 21). Oft ist es nicht möglich Zirrhoseknoten von frühen Stadien einer Neoplasie (FNH oder Leberzellkarzinom) in Ultraschall, Computertomogramm oder MRI zu unterschieden.

 

 

 

 

Leberzelladenom

Leberzelladenom

Das Leberzelladenom (Abb. 22) ist eine Wucherung der Leberzelle selbst. Er kommt überwiegend bei Frauen zwischen 20 und 40 Jahren vor. In der Leber finden sich meistens einzelne Adenomknoten, die jedoch einen Durchmesser von bis zu 30 cm annehmen können und in der Regel keine Kapsel haben.

Im Adenomknoten findet man eine Anreicherung von Fetten und Zucker. Verbunden mit diesem Tumor sind gelegentliche, lokale Einblutungen und abgestorbene Leberzellen in den Knoten, was bei 10% der Patienten die ersten Beschwerden in Form von Oberbauchschmerzen hervorrufen kann. Dieses Blutungsrisiko sowie ein dem Adenom zugesprochenes Entartungsrisiko (Vorstadium eines Leberzellkrebses) sind die Grundlagen, weshalb ein Leberzelladenom heute als eine Präkanzerose (Vorstufe eines Tumors, der zu einem bösartigen Tumor führen kann) angesehen wird und deshalb in der Regel chirurgisch entfernt werden muss.

 

Fokal Noduläre Hyperplasie

Fokal Noduläre HyperplasieDie Fokal Noduläre Hyperplasie, kurz FNH (Abb. 23) ist eine Erkrankung der Leber, die bei Männern und Frauen jeden Alters gefunden wird, wobei Frauen etwas häufiger betroffen sind. Bei Frauen wird ein Zusammenhang mit der Einnahme von Hormonen zur Verhütung diskutiert. Im Gegensatz zum Leberadenom findet man bei der FNH alle Ursprungszellen der Leber in der Gewebewucherung wieder.

Die Leber zeigt bei der FNH ein knotiges Tumorgewebe mit einer charakteristischen Narbe im Zentrum des Tumors und mit sternförmig nach aussen verlaufenden, bindegewebigen Strängen. Diese narbe wird meistens in der US- und CT- Untersuchung sehr gut gesehen und ist ganz typisch für die FNH. Dieser Tumor ist gutartig und muss eigentlich nicht entfernt werden. Häufig bleibt aber bei den abklärenden Untersuchungen doch eine Restunsicherheit gegenüber einem Adenom, das entfernt werden sollte, so dass auch die FNH operativ entfernt werden muss.

 

 

How do I recognize benign liver tumours?

The discovery of a benign liver tumour is normally a random diagnosis in the course of an ultrasound examination or of other diagnostic measures because the patients are in most cases free of pain. Most frequently, patients with a liver cell adenoma complain of untypical pains in the right upper abdomen as well as of bloating, slight nausea, or fever. In comparison with other benign tumours of the liver, one finds here sometimes slightly changed liver factors, which may hint at a biliary stasis caused by the tumour. Unfortunately, the often already voluminous blisters of the dog or fox tapeworm hardly cause any complaints. In many cases, only a blockage of the bile ducts, accompanied by a yellow colouring of the skin, is the only hint at this disease.

Necessary clarifications and diagnostic possibilities

gutartiger lebertumorEven if the majority of the benign liver tumours are discovered through an ultrasound examination, a precise questioning and a physical examination by the doctor will be necessary because the sequence of the complete diagnostics must clearly serve a characterization and confirmation of the benignancy of the tumour. One example: the distinction between a liver cell adenoma and a liver cell carcinoma may prove very difficult in spite of most modern diagnostic methods. Up to 40% of the pathological changes found by chance cannot be unequivocally identified. Thus, it is important to find out whether the patient has lost weight and since when he has suffered from pains in the upper abdomen. Furthermore, it has to be clarified whether there was a previous tumour disease and whether hormones were taken for some years. Other questions are: Is the patient a farmer or a forester, or is he in frequent contact with a large amount of animals? To clarify the case further, a blood count, liver factors, and tumour markers must be used to confirm the benignancy of the tumour. The clarification whether there is a fox or dog tapeworm makes a special examination of the blood necessary, which searches for existing antibodies against the larva. First, ultrasound will be used as the simplest method of diagnosis in all cases of liver disease. Only then, a decision will be made whether further methods like CT, MRI, or angiography will be used for an exact diagnosis. If the diagnosis indicates that part of the liver has to be removed, further special examinations are carried out to test the functional soundness of the healthy liver tissue.

 

How can a benign liver tumour be treated?

The methods of treatment in the case of benign liver tumours include medicinal and surgical measures. The latter is discussed in the chapter about "Malignant Tumours of the Liver" because the technique for the removal of liver tissue is almost identical.

In the case of haemangiomas of the liver, surgical indications are given with great restraint as advantages and risks have no sound relation to each other. So, they are simply left in the liver tissue. They are also not punctured as the risk of bleeding is too high, and patients are advised not to take contraceptive hormones as they might stimulate the growth of the haemangiomas. Only in case of very voluminous haemangiomas or if they cause complaints, a surgical intervention has to be considered, carefully measuring advantages and risks. If an operation should become necessary, one would resort to a so-called enucleation, which means that the capsule of the haemangioma is totally extracted from the liver tissue.

The liver cell adenoma is looked upon as being a precursor of a liver cell carcinoma and must therefore be surgically removed. Depending on the location of the adenoma in the liver, central or at the rim, the surgeon chooses a method of removal by which the tumour is totally excised, the healthy tissue conserved, and the least surgical risk taken in favour of the patient. Operations, in which parts of the liver must be removed, are subject to an increased risk of bleeding due to the highly complicated blood supply of the liver, thus posing a great challenge to the surgeon. Has a FNH (focal nodular hyperplasia) been clearly diagnosed, an operation is not indicated, but female patients are advised not to take contraceptive hormones. This is done because scientists surmise that its formation is triggered by hormones. But often, the diagnosis of FNH is not safe enough, or it causes complaints because of its size and location, so that a surgical removal becomes inevitable. There are two principles as to the therapy of the cysts caused by the dog or fox tapeworm:

If at all possible a surgical treatment will be used, strictly focussing on the criteria of tumour surgery not to spread larvae cells.

All patients have to take the vermicide mebendazol.

As to the cysts of the dog tapeworm, a surgical treatment is first choice with the objective to radically remove the parasite. The prerequisite for this is above all a favourable location of the cysts, so that the surgeon is able to excise them without danger (pericystectomy). If the cysts are diffusely spread in the liver tissue, the surgeon must carry out a removal of the liver. The more radical the operation, the less probable it is that the inflammation reoccurs. If the general state of health of a patient or an unfavourable distribution of cysts does not permit an operation, there are two methods that could be used:

In a laparascopic operation (keyhole surgery), a special instrument is used to evacuate the cyst under strict control and dermabrade the capsule. At the same time, the above mentioned vermicide is applied in the form of pills.

The cyst is punctured with a needle under sonographic control and the content is drained. Then, the surgeon fills a fluid into the cyst to exterminate the larvae and is left there for 15 minutes, then the liquid is removed again. Also in this case, the patient needs to take the vermicide afterwards.

For the cysts of the fox tapeworm, the same principles are valid, with the only exception that the larvae normally spread in the liver much more aggressively. Consequently, a radical surgical solution has to be aimed at - if at all possible. In addition to that, an accompanying application of medicaments for up to 24 months or even longer becomes necessary.

What happens after the treatment?

If the ultrasound shows a small haemangioma, a few systematic ultrasound controls in the following years will be necessary to assess its size. After the removal of an adenoma, the patient will stay at the intensive care unit for 1 - 2 days and then be mobilized as fast as possible. The liver regenerates the missing parts of its tissue within 6 - 7 weeks. At the same time, the most important liver values are controlled to make sure that the liver has taken up all its functions again. After this procedure, the patient is cured, but should receive aftercare: ultrasound controls, but also CT and laboratory controls to monitor the development, if needed. In case of an FNH (focal nodular hyperplasia), there is also the recommendation for female patients to avoid contraceptive hormones and to undergo a regular ultrasound control. The patients with an infection of the fox or dog tapeworm unfortunately have to live with the fact that they more or less have to stay under medical treatment for the rest of their lives. This is true for patients who underwent surgery in the same way as for those who received a medicinal therapy. Unfortunately, there is still no blood test or any other method to prove that the parasites were totally removed from the body. Side effects of the vermicide are changes in the blood picture, divergent liver factors, and loss of hair. The spectre of aftercare therefore comprises regular laboratory examinations to control the effective level of mebendazol and, for instance, CT and MRI.

What has to be paid attention to in future everyday life?

The patients can lead a perfectly normal life. Only some have to undergo certain aftercare examinations.

History

Already in Greek mythology, that is to say in the story of Prometheus, the liver plays an important role: Prometheus, "the one who thinks ahead", tried to cheat Zeus in favour of man, and Zeus in turn withdrew the fire from man as a penalty. But Prometheus stole the fire again to bring it back to earth. So Zeus had him chained to a rock, where eagles came to tear his liver to pieces every day, which, however, renewed itself during the night until Heracles one day liberated him from his pains. This story hints at one of the most important qualities of the liver: its capability for regeneration. For centuries, it had been mainly the military surgeons who tried to treat open injuries of the liver. But then, it was the introduction of general anaesthesia and antisepsis at the end of the 19th century that enabled Karl Langenbuch to perform the first operation of the liver in 1888. At the same time, the basic research as to the regeneration of the liver and the arrest of bleeding (haemostasis) in the liver was carried out. Between 1899 and 1914, it was especially the Viennese surgeon and scientist Emerich Ullmann, who relatively unnoticed promoted the research of transplantation and who must therefore be called "father of organ transplantation", if only belatedly. Yet, the foundation for modern liver surgery was laid in the fifties by the great Parisian school led by Jacques Hepp. In 1954, his assistant Claude Couinaud published the standard work on the anatomy of the liver. He was able to prove the complex inner structure of eight sections, which are determined by the liver veins. Also, the immunology of transplantation had greatly progressed in the meantime. So in 1967, Tom Starzl was able to carry out the first successful transplantation of a liver even if the immunosuppressive therapy was still insufficient. The scientific efforts to develop immunosuppressive therapies went on until 1972. Then, by chance, a substance called cyclosporine was found, drawn from a fungus that grows in the earth. It was able to reliably suppress the rejection of an organ, and consequently, the rate of survival of transplanted patients rose dramatically.

 

back to top

 

© 2017 Baermed. All rights reserved                                                                                                Webdesign by Andreas Dirks