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since its introduction in 1991 , laparoscopic adrenalectomy ( la ) has rapidly become the procedure of choice for the surgical management of most adrenal tumors , and the indications for la have expanded since its first description . however , the use of la for pheochromocytomas is still controversial , and the role of this procedure continues to be undefined .
furthermore , surgeons were initially hesitant to resect pheochromocytomas laparoscopically because of the potential hemodynamic effects of catecholamine secretion during pneumoperitoneum and tumor manipulation .
the development of preoperative localization , the improvement of pre- and perioperative pharmacologic and anesthetic management , combined with maturation of laparoscopic techniques have led to more patients with pheochromocytoma being safely cured laparoscopically . on the other hand , for more surgeons , invasive adrenal carcinoma is an absolute contraindication for la , and whether la should be proposed for large ( > 6 cm ) or potentially malignant tumors is questionable .
the risk of malignancy increases with the size of pheochromocytomas , but the size does not reliably predict malignancy in pheochromocytomas with local disease only .
some authors have demonstrated that the laparoscopic approach for pheochromocytomas yields results comparable to those of open resection .
others have reported series demonstrating the feasibility or results of la for large and potentially malignant tumors .
the aim of this study was to evaluate the risks and outcome of la performed in our department with large ( > 6 cm ) and potentially malignant pheochromocytomas .
during the last 8 years , 48 adrenalectomies , 36 of which were la , have been performed in our department in 47 patients .
we selected 5 patients with large pheochromocytomas . in none of these patients did a preoperative investigation demonstrate invasive carcinoma or preoperative evidence of extraadrenal disease .
the following data were recorded : patient 's age and sex , preoperative diagnosis , final size of tumor , intra- and postoperative complications , operation time , final histological diagnosis , and length of postoperative stay .
the diagnosis of pheochromocytoma was based on elevated levels of vanillylmandelic acid and unexpected high levels of metanephrin or normetanephrin .
the localization of the lesions was accomplished with high - resolution computed tomography ( ct ) , magnetic resonance imaging ( mri ) , and radio - labeled meta - iodobenzylguanidine ( mibg ) to exclude extraadrenal disease .
all 5 patients received preoperative preparation with alpha - blockers ( phenoxybenzamine ) , and in 3 of them a combination of beta - blockers was administered for treatment of tachycardia .
preoperatively , phenoxybenzamine was administered in a daily dose of 20 mg to 40 mg .
the minimal duration of preoperative administration was 20 days , and the maximum was 30 days to obtain sufficient hemodynamic correction and blood volume expansion .
restoration of intravascular volume was determined by the stabilization of arterial pressure for at least 2 weeks plus the absence of orthostatic hypotension and a 10% decrease in hematocrit ( hct ) values .
the preferable surgical approach was the lateral transperitoneal laparoscopic procedure , placing the patient in the lateral decubitus position with the affected side up .
this approach offers a large working space , easier removal of large tumors , and a facile conversion to open adrenalectomy if necessary , according to our department experience , which is over 130 adrenalectomies in the last 25 years .
the incision in case of conversion was placed at the line formed by the 3 anterior trocar sites . during surgery ,
blood pressure was strictly monitored by arterial line , and intravenous alpha- and beta - blockade was administered as necessary .
an abdominal drain was placed in all patients for 20 hours to 24 hours on the adrenal bed .
the cohort included 2 males and 3 females with a median age of 48 years ( range , 29 to 64 ) .
the localizationof pheochromocytomas was 4 in the right side and 1 in the left , the smallest located left .
patient characteristics the adrenal gland had brown pigmentation , and the tumor was paraganglioma with local invasion behind the tail of the pancreas . conversion to open was decided upon after ligation of the adrenal vein because of intraoperative evidence of retroperitoneal invasion .
postexcision tumor size measured 6.5 cm to 15.2 cm ( median , 10.8 ) , which represents the real one , but the maximal diameter at ct or mri and on histological examination was significantly different .
so , at ct and mri the size of the lesions was estimated from 5.5 cm to 13 cm , which means a difference of 20% especially for the right - sided ones . on the other hand ,
the maximum diameter on histological examination was about 15% to 25% smaller ( 4.5 cm to 12 cm ) due to severe blood loss after tumor removal and dehydration due to formaldehyde solution ( table 2 ) .
tumor characteristics the first step of la in all patients with right - sided lesions was dissection of the adrenal vein from its medial attachment from the inferior vena cava and then successful ligation of the adrenal vein with staples , which was rather easily recognized at the front surface of the mass .
the diameter of the adrenal vein was about 2 mm to 5 mm , which is very small for these large pheochromocytomas . on the contrary , the veins of the adrenal bed formed a network of very large vessels draining behind the vena cava prespinally or to the renal vein .
accordingly , this was the most difficult step of the excision with the highest risk of hemorrhage or capsular disruption .
the mobilization of the gland from the inferolateral site to its anteromedial boundaries was very helpful and time saving , with minimal blood loss .
vessel ligation performed through ultrasound scissors or endoscopic gastrointestinal approximator ( endogia ) stapler or laparoscopic clips even with monopolar electro diathermy wherever appropriate .
no capsular disruption occurred during the tumor dissection , and the lesions were resected en block with the adrenal cortex .
the median blood loss was > 150 ml ( range , 80 to 300 ) . no hypertension storm ( systolic blood pressure > 220 mm hg ) , tachycardia ( > 110 beats / min ) , before tumor removal , or severe hypotension , after vessel ligation , occurred , which was the result of the prolonged ( > 20 days ) and sufficient hemodynamic correction .
conversion to open adrenalectomy was performed in 2 patients due to intraoperative evidence of malignancy . in the first patient after the adrenal excision , which was large ( 6 cm ) and macroscopically had brown pigmentation ,
histological examination revealed brown pigmentation of the adrenal gland , and malignant pheochromocytoma of resected paraganglion with a small invasion of the capsule and attached fat . in the second patient after ligation of the adrenal vein
, there was evidence of vena cava and retroperitoneal invasion with major technical difficulties , so conversion to open adrenalectomy was decided upon ( 4th in table 1 ) .
all patients were postoperatively normotensive , and intravenous administration of fluids lasted from 24 hours to 36 hours .
the median length of stay was 3.5 days ( range , 2 to 5 ) .
since its initial report , laparoscopic adrenalectomy has become the preferred approach for surgical adrenal disease . although pheochromocytoma was initially considered a contraindication to laparoscopy , la is evolving as the standard of care . increasing numbers of series
support the safety and efficacy of la for pheochromocytoma . the combination of pneumoperitoneum and the catecholamine effects of pheochromocytomas during laparoscopy present a unique perioperative management challenge to maintain hemodynamic stability .
it is well known that during laparoscopy carbon dioxide pneumoperitoneum increases intraabdominal pressure and thus reduces systemic venous return .
furthermore , pneumoperitoneum may increase sympathetic tone and thus increase peripheral vascular resistance and operative risk of hemodynamic instability .
inabnet et al directly compared intraoperative hemo - dynamic parameters for 22 patients undergoing adrenalectomy for pheochromocytoma by open and laparoscopic approaches .
there was no significant change in cardiac index or left ventricular work , but they found increased numbers of intraoperative hypertensive events for patients undergoing laparoscopy .
the majority of authors agreed that the adequate preoperative preparation with alpha blockers , for sufficient blood volume correction , combined with careful manipulation of the tumor , correct regulation of gas pressure ( 8 to 13 mm hg ) and successful management of problems by an experienced anesthetic team can reduce the release of adrenergic substances .
it appears that a period of 10 days to 12 days for preoperative preparation with alpha - blockers is inadequate to restore blood volume . in large pheochromocytomas , we tried phenoxybenzamine administration for at least 20 days in low doses ( 20 mg to 40 mg ) .
surprisingly , a significant drop in hct occurred ( 8% to 10% ) in all cases , indicating intravascular volume restoration .
we believe that the importance of adrenal vein early ligation in large and right - sided pheochromocytomas is a myth .
the adrenal vein in these lesions was always found at the front side of the mass and surprisingly not large in size ( 2 mm to 5 mm ) .
so after the recognition and dissection of the inferior vena cava , the preparation and ligation of the adrenal vein was rather easy .
particularly in all right - sided tumors , we observed that veins of the adrenal bed formed a remarkable network of very large vessels draining behind the vena cava prespinally or to the renal vein .
this was the most difficult step of the excision with the highest risk of hemorrhage or capsular disruption .
the mobilization of the gland from the inferolateral site to its anteromedial boundaries was very helpful and time saving , with minimal blood loss , and no capsular disruption .
on the other hand , no severe hypotensive episode occurred after the total mass excision due to adequate intravascular volume expansion .
the diagnosis of malignant pheochromocytoma can only be made reliably by the findings of local invasion , nodal or distal metastasis .
no accurate histologic criteria for the diagnosis existed , and 2.5% to 26% of pheochromocytomas are malignant and are only identified during follow - up .
malignant pheochromocytoma is more likely in extraadrenal locations ( 30% to 40% ) and tumors of 6 cm or larger .
many surgeons have traditionally used a size greater than 6 cm as a contraindication to laparoscopic resection .
some studies favor the opinion that laparoscopy can also be indicated for large and potentially malignant tumors.5 our data support this theory , and the size of the tumor has not been used as a criterion for exclusion of la . in cases with no preoperative evidence of extraadrenal disease , the possibility of malignancy can be proved only intraoperatively , if evidence of local invasion is found .
so , in our series , all patients underwent la , and in 2 patients there was evidence of local invasion ( of the smaller and larger lesions ) .
in experienced hands , la can be proposed for large pheochromocytomas without preoperative signs of malignancy with no difference in postoperative morbidity or mortality .
conversion to open adrenalectomy should be performed if local invasion is observed during surgery or technical difficulties are encountered
background and objectives : the majority of surgeons consider large and potentially malignant pheochromocytomas an absolute contraindication for laparoscopic adrenalectomy ( la ) . 
 the aim of this study was to evaluate the risks and outcomes of la in patients with this anomaly.methods:five patients ( 2 males , 3 females ) with large ( > cm ) pheochromocytomas were selected . 
 preoperative investigation demonstrated no evidence of invasive carcinoma . 
 all patients received alpha - blocker preparation for at least 20 days . 
 laparoscopic adrenalectomy via a lateral transperitoneal approach was performed in all cases.results:patient's median age was 48 years , and the median tumor size was 10.8 cm . 
 no capsular disruption and no hypertensive crises occurred during the operation . 
 the median operating time was 148 minutes and blood loss was < 150 ml . 
 conversion to open adrenalectomy occurred in 2 patients owing to intraoperative evidence of carcinoma . 
 no postoperative morbidity or mortality occurred . 
 all patients are disease free after a median follow - up of 13 months.conclusions:in experienced hands , la can be proposed for large and potentially malignant pheochromocytomas . 
 conversion to open adrenalectomy is mandatory if local invasion , capsular disruption , or technical difficulties are observed during the operation .