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mean life expectancy has been increasing in many countries , and the management of malignancies in the elderly has thus become a global issue [ 1 , 2 , 3 ] .
hepatocellular carcinoma ( hcc ) is a common malignant tumor with poor prognosis , and the numbers of elderly patients with hcc are expected to increase around the world .
several studies in the 1990s and early 2000s reported significantly higher rates of morbidity and mortality after hepatectomy in elderly patients [ 5 , 6 , 7 , 8 ] . on the other hand
, recent studies have found that the short- and long - term outcomes of hepatectomy in elderly patients are similar to those in younger patients [ 4 , 9 , 10 , 11 , 12 ] .
the indications for hepatic resection in elderly patients have been questioned , and given the increasing number of affected elderly patients , this issue requires serious consideration .
he underwent a medical examination for hypertension and chronic atrial fibrillation , during which a mass was palpated through the abdominal wall .
iu / l ( normal 530 ) , alkaline phosphatase ( alp ) 334 u / l ( normal 115359 ) , gamma - glutamyl transferase ( -gtp ) 230 iu / l ( normal 050 ) , lactate dehydrogenase ( ldh ) 177 iu / l ( normal 106211 ) , albumin ( alb ) 3.6 g / dl ( normal 3.75.5 ) , total bilirubin ( tb ) 0.71 mg / dl ( normal 0.21.0 ) , and prothrombin time - international normalized ratio ( pt - inr ) 1.03 .
child - turcotte - pugh grade was a. the indocyanine green retention rate at 15 min ( icg - r15 ) was 8% .
the concentration of serum alpha - fetoprotein ( afp ) was 3,600 ng / ml ( normal < 20 ) and plasma des--carboxy prothrombin ( dcp ) , also known as protein induced by vitamin k deficiency or antagonist - ii , was 93,300 mau / ml ( normal < 40 ) .
contrast - enhanced computed tomography ( cect ) revealed a tumor measuring 78 mm in diameter in the left lateral sector of the liver ( fig .
the operation time was 370 min , and the amount of blood loss was 978 ml .
laboratory data were as follows : ast 35 iu / l ( normal 535 ) , alt 21 iu / l ( normal 530 ) , alp 198
iu / l ( normal 050 ) , ldh 162 iu / l ( normal 106211 ) , alb 2.9 g / dl ( normal 3.75.5 ) , tb 0.7 mg / dl ( normal 0.21.0 ) , and pt - inr 1.18 .
the concentration of serum afp was 1,210 ng / ml ( normal < 20 ) and plasma dcp was 209 mau / ml ( normal < 40 ) .
cect revealed a tumor measuring 20 mm in diameter in segment 2 of the liver , accompanied by tumor thrombi toward the main left portal vein ( fig .
the patient requested radical surgery , so left hemi - hepatectomy was performed ( fig .
the operation time was 304 min , and the amount of blood loss was 379 ml .
he underwent a medical examination for hypertension and chronic atrial fibrillation , during which a mass was palpated through the abdominal wall .
iu / l ( normal 530 ) , alkaline phosphatase ( alp ) 334 u / l ( normal 115359 ) , gamma - glutamyl transferase ( -gtp ) 230 iu / l ( normal 050 ) , lactate dehydrogenase ( ldh ) 177 iu / l ( normal 106211 ) , albumin ( alb ) 3.6 g / dl ( normal 3.75.5 ) , total bilirubin ( tb ) 0.71 mg / dl ( normal 0.21.0 ) , and prothrombin time - international normalized ratio ( pt - inr ) 1.03 .
child - turcotte - pugh grade was a. the indocyanine green retention rate at 15 min ( icg - r15 ) was 8% .
the concentration of serum alpha - fetoprotein ( afp ) was 3,600 ng / ml ( normal < 20 ) and plasma des--carboxy prothrombin ( dcp ) , also known as protein induced by vitamin k deficiency or antagonist - ii , was 93,300 mau / ml ( normal < 40 ) .
contrast - enhanced computed tomography ( cect ) revealed a tumor measuring 78 mm in diameter in the left lateral sector of the liver ( fig .
the operation time was 370 min , and the amount of blood loss was 978 ml .
laboratory data were as follows : ast 35 iu / l ( normal 535 ) , alt 21 iu / l ( normal 530 ) , alp 198
u / l ( normal 115359 ) , -gtp 67 iu / l ( normal 050 ) , ldh 162 iu / l ( normal 106211 ) , alb 2.9 g / dl ( normal 3.75.5 ) , tb 0.7 mg / dl ( normal 0.21.0 ) , and pt - inr 1.18 .
the concentration of serum afp was 1,210 ng / ml ( normal < 20 ) and plasma dcp was 209 mau / ml ( normal < 40 ) .
cect revealed a tumor measuring 20 mm in diameter in segment 2 of the liver , accompanied by tumor thrombi toward the main left portal vein ( fig .
the patient requested radical surgery , so left hemi - hepatectomy was performed ( fig .
the operation time was 304 min , and the amount of blood loss was 379 ml .
mean life expectancy has been increasing in many countries , and the management of malignancy in the elderly has become a global issue [ 1 , 2 , 3 ] .
general markers of liver function , such as levels of ast , alt , serum tb and alp , are largely unaffected by aging .
in contrast , decreases are seen in serum levels of alb , some amino acids and some coagulation factors , including fibrinogen , prothrombin and thromboplastin .
several studies in old rodents have suggested that aging compromises the regenerative capacity of the liver after hepatectomy or ligation of the portal vein [ 16 , 17 ] .
advanced age is already a high risk factor for staying alive , and the risks associated with surgical treatment are thus considered to be further magnified .
furthermore , advanced age increases complications such as high blood pressure and diabetes mellitus . in recent years , hepatectomy for much more elderly patients has been attracting increasing attention .
several studies in the 1990s and early 2000s reported significantly higher rates of morbidity and mortality in elderly patients [ 5 , 6 , 7 , 8 ] . on the other hand ,
recent studies have reported the safety of surgery in elderly patients [ 4 , 9 , 10 , 11 , 12 ] .
the age standards for hepatectomy are rising because hepatectomy is being performed with increasing safety .
after stringent criteria for hepatectomy were proposed , the mortality rate decreased markedly . with the development of surgical energy devices , such as vessel - sealing instruments and ultrasonic surgical devices ,
furthermore , in recent years , the laparoscope for hepatectomy has been attracting attention as a means to reduce surgical stress .
such developments are contributing to the increasing use of hepatectomy and the increasing standard age of recipients .
however , the optimal age limits remain unclear . in our department , we place emphasis on anesthetic procedures to reduce surgical stress .
we have been able to perform major hepatectomy in patients over 90 years old with no postoperative complications . here , we reported two cases of successful treatment for patients over 90 years old , and our cases represent the oldest cases yet described to have undergone major hepatectomy .
case 2 remarked that elderly patients who were afraid of undergoing surgery at her age could be encouraged by her results .
hepatocellular carcinoma ( hcc ) is a common malignant tumor with poor prognosis . 
 the age of patients affected by hcc is considered to be increasing , and several studies have reported significantly higher rates of morbidity and mortality after hepatectomy for hcc in elderly patients . 
 however , other studies have reported that the short- and long - term outcomes of surgery for hcc in elderly patients are similar to those in younger patients . 
 whether the indications for hepatic resection in elderly patients resemble those in younger patients has thus been questioned . 
 we describe two cases of patients over 90 years old who underwent major hepatectomy for hcc , representing the oldest patients in the world to have done so .