**9. Alveolar cysts (***E. alveolaris* **=** *E. multilocularis***)**

It forms 2–3% of liver cysts. In radiological imaging techniques, it is seen as the cyst wall makes papillary extensions into the liver parenchyma, which may resemble a hepatic tumor that leaks clinically and radiographically with irregular edges and heterogeneous density [18]. This formation is very important because if a part of the liver parenchyma is not resected in the surgery, there may remain a part of the germinative membrane which will cause recurrences (**Figure 6**).

There is also a PNM staging for alveolar echinococcal disease. P in the PNM shows the state of the parasite in the liver, N shows adjacent organ involvement, and M is for metastasis. Accordingly, PNM staging is as follows:

P: Shows the localization of the metacestode in the liver.

PX: Parasitic lesion cannot be evaluated.

P0: No parasitic lesion in the liver.

P1: Peripherally located and without biliary or proximal vascular involvement.

P2: Central lesion involving the biliary or proximal vascular structures in a single lobe.

P3: Central lesion involving the biliary or proximal vascular structures of two lobes, or involving two hepatic veins, or both.

P4: Any lesion extending along the portal vein, inferior vena cava, or hepatic artery.

N: Shows extrahepatic involvement to neighboring organs.

Nx: Unable to evaluate.

N0: No regional involvement.

#### **Figure 6.**

*Alveolar* Echinococcus *lesion in right liver lobe shown in abdominal CT scan. Partial calcifications are seen around the lesion and left lobe is hypertrophied. Differential diagnosis with hemangioma is done with biopsy [3].*

**111**

**Author details**

Mehmet Mihmanli\*, Mert Tanal, Emre Bozkurt and Onur Guven

Hospital, Health Sciences University, Istanbul, Turkey

provided the original work is properly cited.

\*Address all correspondence to: mmihmanli@yahoo.com

Department of General Surgery, Sisli Hamidiye Etfal Research and Training

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

*The Surgical Management of Hydatid Cyst of the Liver: What is New?*

The only treatment of alveolar hydatid cyst is surgery. Interventional radiological methods are not recommended. The surgical treatment should be pericystectomy, in which intact liver tissue of at least 1 cm should be excised with cyst. Within all operated hydatid cyst cases in Turkey, the ratio of alveolar echinococcus is about

MR and MRCP, and ERCP if necessary, are used preoperatively in each case considered for surgical treatment. Since pericystectomy will be performed, it should be known whether there is an invasion to the bile ducts, portal vein, or inferior vena

Albendazole is used in cases where surgical treatment cannot be applied and in the postoperative period as well (as in case of all hydatid cysts). However, their daily dose should be higher, and the duration of use has to be much longer (at least

In conclusion, alveolar hydatid cyst is a more resistant type and requires more

N1: Involvement of neighboring organs or tissues.

*DOI: http://dx.doi.org/10.5772/intechopen.90726*

aggressive surgery and medical treatment.

The authors declare no conflict of interest.

M: The situation of metastasis.

M0: No metastasis. M1: Metastasis.

15-25%.

cava.

1 year).

**Conflict of interest**

*The Surgical Management of Hydatid Cyst of the Liver: What is New? DOI: http://dx.doi.org/10.5772/intechopen.90726*

N1: Involvement of neighboring organs or tissues. M: The situation of metastasis. M0: No metastasis. M1: Metastasis.

The only treatment of alveolar hydatid cyst is surgery. Interventional radiological methods are not recommended. The surgical treatment should be pericystectomy, in which intact liver tissue of at least 1 cm should be excised with cyst. Within all operated hydatid cyst cases in Turkey, the ratio of alveolar echinococcus is about 15-25%.

MR and MRCP, and ERCP if necessary, are used preoperatively in each case considered for surgical treatment. Since pericystectomy will be performed, it should be known whether there is an invasion to the bile ducts, portal vein, or inferior vena cava.

Albendazole is used in cases where surgical treatment cannot be applied and in the postoperative period as well (as in case of all hydatid cysts). However, their daily dose should be higher, and the duration of use has to be much longer (at least 1 year).

In conclusion, alveolar hydatid cyst is a more resistant type and requires more aggressive surgery and medical treatment.
