**7.1 Surgical resection**

The indications for surgery in nonemergent cases are: HA > 5 cm, female patients taking oral contraceptives with HA > 3 cm [47], HA with growing size, HA with HCC or dysplastic foci, β-catenin-activated HA, imaging features of malignant transformation, increased serum alpha fetoprotein, HA in males regardless of the tumor size, HA in GSD, symptomatic patients, or when malignancy cannot be excluded [54]. The type of resection depends mainly on number, size, histological type, and localization of HA. The resection techniques vary from simple enucleation to liver transplantation [55]. Liver resection for HA can be anatomic or nonanatomic. Anatomic resections reported in the literature for HA refer to minor hepatectomies that imply the removal of the tumor with one or two segments of the liver [56], but also major hepatectomies like left and right hemihepatectomy, mesohepatectomy [57], and left or right extended hepatectomy [26, 58]. Nonanatomical resections are wedge resections [59]. Enucleation seems to be a choice for such benign tumor, but is not advisable due to the risk of remnant tumor that can cause tumor recurrence or, worse, malignant degeneration, especially for β-catenin HA. It was speculated that the classical 1 cm oncological safety margin could be lowered to 0.5 cm for HA. The safety margin at the edge of resection is mandatory, if any suspicion of HCC exists.

Surgery in elective cases is less than 1% and most tumors can be operated laparoscopically, with significant advantages [59–61]. A better cosmetic result, a shorter hospitalization (4 days) with early return to normal life, and a lower incisional rate are the main advantages that laparoscopy has comparative with open approach. However, laparoscopy should be performed only in specialized centers with extensive experience in both hepatic and laparoscopic surgery. The first non-anatomical laparoscopic liver resection for HA reported by Ferzli et al. [62] in 1995 was followed one year later by the first anatomic laparoscopic resection for HA performed by Azagra et al. [63]. Pure laparoscopic procedure can be performed for HA with no mortality and reduced morbidity even in

hemodynamic stable patients with ruptured HA [61]. Moreover, some surgeons consider laparoscopic surgery the standard of care for the treatment of HA [59]. Hand-assisted or "hybrid" techniques are also optional approaches [64] and the parietal incision is later used for specimen retrieval. In pure laparoscopic surgery, the specimen is retrieved through a Pfannenstiel incision even when the tumor is as large as 180 mm [61].

Pringle maneuver can be of great use to minimize the intraoperative blood loss and it is used by surgeons both in laparotomy and laparoscopy. Some authors consider it unnecessary for laparoscopic left lateral sectionectomy [60]. Instead, others perform the maneuver for both atypical and anatomical resections. Laparoscopy is restricted by the localization of HA involving segments VII and VIII. The half-Pringle maneuver was associated for right posterior sectionectomy and resulted in less bleeding [65].

Total vascular exclusion of the liver is routinely recommended in high dorsal resections for HA [66].

Intraoperative blood transfusion is rarely needed and generally is performed in case of ruptured bleeding adenoma. Conversion of laparoscopy to laparotomy should be considered just in case of too much bleeding and difficulties for the anesthesiologist to stabilize the patient.

The high rates of mortality and morbidity previously reported after liver resection for bleeding HA are recently denied by new evidences [30]. Emergency resection of ruptured HA has a mortality rate of 5–10%, whereas elective surgery has a mortality rate of less than 1% [67]. These results are explained nowadays by the availability of improved hemostatic techniques, excellent anesthesia support, and postoperative intensive care. In the past, in the presence of signs of hemorrhagic shock, the mortality was as high as 20% for resection [68]. At present, the mortality for such patients trends toward zero. Nonsurgical strategies such as arterial embolization or gauze packing have been recommended in order to stabilize the patient and delay resection to an elective setting. There are situations when intraperitoneal bleeding from a ruptured adenoma is self-limited and a laparotomy is done just for biopsy. A recent bleeding adenoma does not necessarily need resection. After this acute bleeding, some of these tumors regress, others are stationary, and few rebleed. Transarterial embolization (TAE) can not only stabilize the patient but also obtain complete avoidance of surgical intervention. Sometimes, repeated embolization is needed to achieve hemostasis. However, liver resection remains the best means to achieve hemostasis and also to obtain a thorough histology.
