Laparoscopic vs Open Adrenalectomy for the Treatment of Primary Hyperaldosteronism
Wen T. Shen, MD; Robert C. Lim, MD; Allan E. Siperstein, MD; Orlo H. Clark, MD; William P. Schecter, MD; Thomas K. Hunt, MD; Jan K. Horn, MD; Quan-Yang Duh, MD
Hypothesis: That the clinical presentations, biochemi- cal profiles, and surgical outcomes of patients treated with laparoscopic vs open adrenalectomy for primary hyper- aldosteronism are different.
Design, Settings, Patients, and Interventions: The medical records of 80 patients with primary hyperaldo- steronism who underwent open adrenalectomy between 1975 and 1986 or laparoscopic adrenalectomy between 1993 and 1998 at the University of California-San Fran- cisco were reviewed by a single unblinded researcher (W.T.S.).
Main Outcome Measures: Severity of hypertension and hypokalemia at diagnosis, their improvement after adrenalectomy, and operative complications.
Results: Thirty-eight patients underwent open adrena- lectomy and 42 patients underwent laparoscopic adrena- lectomy. The patients who underwent open adrenalec- tomy had documented hypertension for a median of 5 years before surgery; all had diastolic blood pressures greater than 100 mm Hg. Laparoscopically treated patients had docu- mented hypertension for a median of 2.5 years preopera- tively, and 20 (48%) had diastolic blood pressures greater than 100 mm Hg. The median preoperative serum potas- sium levels for the open and laparoscopic groups were 2.6 mmol/L and 3.3 mmol/L, respectively; the mean serum al-
dosterone levels were 1.47 nmol/L and 1.30 nmol/L. Thirty- two (84%) of the 38 patients who underwent open sur- gery and 41 (98%) of the 42 patients treated laparoscopically had adrenal adenomas. The sensitivity of preoperative com- puted tomographic scanning for adenomas was 83% for the patients treated with open adrenalectomy and 93% for those treated laparoscopically. There were 4 postoperative com- plications in the open surgery group and none in the lapa- roscopic group. Postoperatively, 30 (81%) of 37 patients (excluding 1 patient who died of adrenocortical carci- noma) in the open surgery group and 37 (88%) of 42 pa- tients treated laparoscopically were normotensive. Post- operative values were 3.6 to 5.0 of serum potassium per liter and 3.5 to 4.9 of serum potassium per liter in the open and laparoscopic groups, respectively.
Conclusions: Patients who are treated with laparo- scopic adrenalectomy for primary hyperaldosteronism are being referred with less severe hypertension and hy- pokalemia than patients formerly treated with open adre- nalectomy. Patients treated laparoscopically had fewer postoperative complications and were equally likely to improve in blood pressure and hypokalemia. Laparo- scopic adrenalectomy has become the treatment of choice for patients with primary hyperaldosteronism because of lower morbidity.
Arch Surg. 1999;134:628-632
From the Department of Surgery, University of California-San Francisco (Drs Shen, Lim, and Hunt); UCSF/Mt Zion Medical Center (Drs Siperstein and Clark); San Francisco Veterans Affairs Medical Center (Dr Duh); and San Francisco General Hospital (Drs Schecter and Horn).
P RIMARY hyperaldosteronism is an uncommon but surgi- cally correctable disease that affects approximately 1 in ev- ery 200 hypertensive pa- tients.1 First described by Jerome Conn in 1954, primary hyperaldosteronism is char- acterized by hypertension, hypokalemia, el- evated plasma aldosterone, and low plasma renin activity. The most common under- lying pathology for this syndrome is an al- dosterone-producing adrenal adenoma. Pri- mary hyperaldosteronism can also be caused by bilateral adrenal hyperplasia and other rarer diseases such as primary uni- lateral adrenal hyperplasia, glucocorticoid-
responsive hyperaldosteronism, and adre- nocortical carcinoma.
The surgical treatment of choice for primary hyperaldosteronism caused by an aldosterone-secreting adenoma is unilat- eral adrenalectomy.2-10 Until recently, this operation required an open surgical pro- cedure, usually through a posterior “Hugh- Young” incision. We have previously reported our experience with open adre- nalectomy for the treatment of primary hy- peraldosteronism in the 1970s and 1980s.11 Since that time, however, several techno- logical advancements have been made in the diagnosis and treatment of this con- dition. Improvements in the sensitivity of
MATERIALS AND METHODS
We retrospectively analyzed the medical records of 80 patients who underwent adrenalectomy for primary hy- peraldosteronism at University of California-San Fran- cisco between 1975 and 1998. Open adrenalectomy was performed in 38 patients between 1975 and 1986. Thirty-four patients underwent unilateral open adre- nalectomy, while 4 patients underwent bilateral open adrenal exploration with removal of 1 adrenal tumor. The patient profiles and results of operation from these 38 patients have been previously reported.11 Laparo- scopic adrenalectomy was performed in 42 patients be- tween 1993 and 1998; all 42 patients underwent uni- lateral exploration and adrenalectomy.
Several biochemical and clinical parameters were measured in the preoperative evaluation of patients in this study. Serial blood pressure measurements were obtained, along with preoperative serum potassium levels, plasma aldosterone levels, and plasma renin activity. Plasma aldosterone levels were measured with the patient in the supine and upright positions, when- ever possible. We also recorded the duration of docu- mented preoperative hypertension. Preoperative lo- calization of the aldosterone-secreting adenomas was done using CT scanning; 5-mm to 1-cm sections were used in 29 (76%) of the 38 patients treated with open adrenalectomy and 3-mm sections were used in all patients who underwent laparoscopic adrenalec- tomy. Other methods of localization included selec- tive adrenal vein catheterization to measure the gra- dient of plasma aldosterone levels, iodocholesterol I 131 adrenal scintigraphy, and NP-59 (1311-6ß- iodomethyl-19-norcholesterol) scanning.
We also studied operative approach (posterior or lateral), complication rates, and tumor pathol- ogy. Postoperatively, we documented blood pres- sures and serum potassium levels as indications of cure. The duration of follow-up ranged from 6 months to 6 years for the patients who underwent open adre- nalectomy and from 4 months to 3 years for the lapa- roscopically treated patients.
computed tomographic (CT) scanning have facilitated the imaging of the adrenal glands.12,13 In addition, the in- troduction of laparoscopic adrenalectomy has dramati- cally altered the approach to surgical treatment of pa- tients with primary hyperaldosteronism.
Within the past decade, laparoscopic adrenalectomy has become an increasingly popular surgical treatment for patients with primary hyperaldosteronism, Cushing syn- drome, and pheochromocytoma.4,5,7,9,10 Since 1993 we have performed more than 150 laparoscopic adrenalectomies, including 42 laparoscopic adrenalectomies for primary hy- peraldosteronism. Few publications have compared the clinical profiles and outcomes of patients treated with lapa- roscopic vs open adrenalectomy for primary hyperaldo- steronism. We therefore decided to analyze our experi- ence with patients with primary hyperaldosteronism and to determine whether there were differences in demograph- ics, biochemical and clinical presentations, and postop-
erative outcomes between patients treated with laparoscopic adrenalectomy and those treated with open adrenalectomy.
RESULTS
The 38 patients treated with open adrenalectomy in- cluded 6 men and 32 women, with a median age of 35 years. The 42 patients who underwent laparoscopic adrenalec- tomy included 29 men and 13 women, with a median age of 50 years. There were statistically significant differences in age (P <. 05, t test) and sex (P <. 05, x2 analysis) be- tween the 2 groups. All patients had documented hyper- tension on serial blood pressure measurements. The me- dian duration of documented hypertension was 5 years for the patients who underwent open adrenalectomy and 2.5 years for the laparoscopically treated patients. All of the pa- tients treated with open adrenalectomy had a diastolic blood pressure of greater than 100 mm Hg without antihyper- tensive medications, whereas only 20 (48%) of the 42 pa- tients treated laparoscopically had diastolic blood pres- sures of greater than 100 mm Hg with no medications.
Preoperative laboratory evaluation included serum po- tassium levels, plasma renin activity, and plasma aldoster- one levels, usually measured with the patient in the su- pine and upright positions. The median serum potassium level was 2.6 mmol/L in the patients who underwent open adrenalectomy and 3.3 mmol/L in patients treated laparo- scopically. There was a statistically significant difference in median serum potassium levels between the 2 groups (P <. 05, t test). Spironolactone, potassium supplements and, occasionally, amiloride were used to correct preoperative hypokalemia. The mean plasma aldosterone level in pa- tients who underwent open adrenalectomy was 1.47 nmol/L (reference range, <0.86 nmol/L); the mean plasma aldos- terone level in laparoscopically treated patients was 1.33 nmol/L. There was no statistical difference in the mean plasma aldosterone levels in the 2 groups. Supine and up- right plasma aldosterone levels were measured in 35 pa- tients treated with open adrenalectomy; 34 (97%) exhib- ited abnormal postural responses (paradoxical decrease or minimal change) in serum aldosterone levels. Abnormal postural responses in plasma aldosterone levels were noted in 14 (93%) of 15 patients who were treated laparoscopi- cally. Plasma renin activity was decreased in all 38 pa- tients who underwent open adrenalectomy and in 39 (93%) of the 42 laparoscopically treated patients.
Preoperative imaging studies differed according to the period during which the operation was performed. The 38 patients treated with open adrenalectomy underwent CT scanning (29 patients), iodocholesterol I 131 adrenal scanning (16 patients), or selective adrenal vein catheter- ization (11 patients). Iodocholesterol I 131 scanning cor- rectly identified the adenoma in 9 (56%) of 16 patients. Computed tomographic scanning correctly identified the adenoma in 22 (83%) of 29 patients. Selective venous cath- eterization was conclusive in 9 (82%) of 11 patients and inconclusive in the remaining 2 patients. All of the 42 pa- tients who underwent laparoscopic adrenalectomy were studied with preoperative high-resolution CT scanning us- ing 3-mm sections (as opposed to the 5-mm to 1-cm sec- tions used in the CT scans of the open adrenalectomy pa- tients). Computed tomographic scanning correctly
identified the adenoma in 39 (93%) of these 42 patients. Selective venous catheterization was performed in 2 pa- tients who underwent laparoscopic adrenalectomy; both of these studies correctly localized the adenoma. Scan- ning with NP-59 was used in 1 patient treated with lapa- roscopic adrenalectomy and correctly identified the ad- enoma. Of note, none of the adrenal tumors were identified incidentally (“incidentaloma”).
Of the 38 patients who underwent adrenalectomy via the open approach, 34 underwent unilateral explo- ration and adrenalectomy, while 4 patients underwent bilateral adrenal exploration and resection of one adre- nal tumor. These 4 bilateral explorations were per- formed because of equivocal localizing studies, and all occurred between 1975 and 1977, which were the first years of our experience included in this study. The 42 laparoscopically treated patients all underwent unilat- eral exploration and adrenalectomy.
Twenty-eight (74%) of the patients treated with open adrenalectomy were operated on through a posterior ap- proach, 6 (16%) underwent lateral exploration, and 4 (10%) underwent exploration bilaterally through an an- terior approach. The 42 laparoscopically treated pa- tients included 28 (67%) who underwent lateral trans- abdominal exploration and 14 (33%) who underwent posterior retroperitoneal exploration.
Of the 38 patients who underwent open explora- tion, 32 had aldosterone-secreting adenomas, 5 had bilat- eral adrenal hyperplasia, and 1 had adrenocortical carci- noma. The five patients with bilateral adrenal hyperplasia were all thought to have adenomas prior to operation; 2 had false-positive CT scans (showing adenomas that were not found in the pathologic specimen) and 3 had nega- tive CT scans (showing no abnormalities). Two patients with hyperplasia achieved normalization of blood pres- sure following unilateral adrenalectomy. The 1 patient with adrenocortical carcinoma exhibited all of the preopera- tive biochemical and symptomatic criteria for an aldoster- one-producing adrenal adenoma. He died of dissemi- nated adrenocortical carcinoma 2 years after surgery.
Forty-one (98%) of the 42 patients who underwent laparoscopic adrenalectomy had histologically confirmed adenomas. The one exception in this group was a patient who had a preoperative CT scan that showed a 2-cm left adrenal adenoma and a possible smaller mass in the right adrenal gland. A laparoscopic unilateral left adrenalec- tomy was performed with removal of a 2-cm adenoma within a hyperplastic cortex; however, the patient contin- ued to be hypokalemic and hypertensive following opera- tion. In retrospect, we found that this patient had bilateral adrenal hyperplasia and a nonfunctioning left adrenal ad- enoma that could have been diagnosed if a preoperative se- lective venous catheterization had been performed based on the CT scan showing possible bilateral abnormalities.
Postoperative complications occurred in 4 (11%) of the 38 patients who underwent open adrenal explora- tion and adrenalectomy. Two patients developed post- operative hypotension and anemia; they required vigor- ous fluid replacement but no transfusions. Two other patients developed postoperative persistent acidosis and hyperkalemia due to mineralocorticoid deficiency. As mentioned, 1 patient with adrenocortical carcinoma died
2 years after the adrenalectomy. No postoperative com- plications occurred in the patients who underwent lapa- roscopic adrenalectomy; the difference in postoperative complication rates between the 2 groups was statisti- cally significant (P <. 05, Fisher exact test).
Postoperatively, 30 (81%) of the 37 patients who un- derwent open adrenalectomy for benign disease became normotensive and no longer required postoperative blood pressure medications. Thirty-seven (88%) of the 42 lapa- roscopically treated patients became normotensive and did not require medications postoperatively. The post- operative serum potassium levels ranged from 3.6 to 5.0 mmol/L in the open adrenalectomy group and from 3.5 to 4.9 mmol/L in the laparoscopic adrenalectomy group. The differences in postoperative blood pressures and se- rum potassium values were not statistically significant.
COMMENT
The results of this retrospective review document that lapa- roscopic adrenalectomy is a safe and effective treatment for primary hyperaldosteronism. Laparoscopically treated patients had fewer postoperative complications and were equally likely to improve in blood pressure and hypokal- emia when compared with patients treated with open adre- nalectomy. Additional benefits of laparoscopic adrenalec- tomy that were not addressed in this study include smaller incisions, decreased postoperative pain, and shorter hos- pitalizations, as reported by others.4,5,7,9,10 All of these fac- tors have contributed to the increasing popularity of lapa- roscopic adrenalectomy for the treatment of patients with primary hyperaldosteronism and, in many medical cen- ters (including our own), the laparoscopic technique has replaced open surgery as the treatment of choice for this condition and other benign adrenal gland tumors.
Besides providing information regarding the safety and efficacy of laparoscopic vs open adrenalectomy for pri- mary hyperaldosteronism, this study also allows us to com- ment on changes that have occurred during the past de- cade in both the diagnosis and clinical presentation at the time of referral of patients with this disease. All of the pa- tients in this study who underwent laparoscopic adrena- lectomy were operated on after 1993, whereas patients who were treated with open adrenalectomy underwent sur- gery between 1975 and 1986. An important technological advancement during the past decade has been the improve- ment of CT scanning. All patients treated laparoscopically were studied with high-resolution CT scanning (3-mm sec- tions), with an overall sensitivity of 93%. In contrast, the patients treated with open adrenalectomy underwent CT scanning (5-mm to 1-cm sections) or other imaging stud- ies, including iodocholesterol I 131 adrenal scanning and selective adrenal vein catheterization; the sensitivity of CT scanning in this group was 83%. When used in conjunc- tion with the appropriate laboratory tests, high-resolution CT scanning has helped endocrinologists and surgeons to differentiate more accurately between an adrenal ad- enoma and bilateral adrenal hyperplasia. This observation is supported by the fact that 32 of 38 patients in the open adrenalectomy group and 41 of 42 laparoscopically treated patients were correctly identified preoperatively as having adrenal adenomas; the differentiation between adenoma and
hyperplasia in patients with primary hyperaldosteronism is crucial because patients with adenomas are almost al- ways responsive to surgery while those with hyperplasia are best managed medically.1,13,14
There were statistically significant differences in the demographic and clinical profiles of patients between the laparoscopic and open groups. Patients who underwent laparoscopic adrenalectomy were older and had been hy- pertensive for a shorter period of time than patients who were treated with open surgery; in addition, there were more men than women in the laparoscopic group (29 men, 13 women), while the opposite was true in the open surgery group (6 men, 32 women). These differences between the 2 groups lead us to believe that we are currently operating on a different population of patients with primary hyper- aldosteronism than we were in previous decades. We of- fer 2 reasons for this change in patient populations. First, improvements in CT scanning have resulted in the earlier detection of aldosterone-secreting adenomas and have there- fore facilitated the diagnosis of patients with less severe dis- ease, including patients whose tumors may have been missed in the decades prior to improved CT scanning. Sec- ond, it is possible that the introduction of laparoscopic adre- nalectomy has altered the referral patterns of primary care physicians and endocrinologists; these physicians may be referring older patients and patients with less severe dis- ease for surgical treatment because they perceive the lapa- roscopic procedure to be less invasive and therefore hav- ing less morbidity for patients.
In conclusion, the improved sensitivity of CT scan- ning during the laparoscopic era has improved the diag- nosis and localization of adrenal adenomas in patients with primary hyperaldosteronism. Patients who underwent lapa- roscopic adrenalectomy for primary hyperaldosteronism had less severe hypertension and hypokalemia than pa- tients treated with open adrenalectomy. In addition, pa- tients treated laparoscopically suffered fewer postopera- tive complications and were equally likely to improve in blood pressure and hypokalemia. As reported in other se- ries, laparoscopic adrenalectomy causes less pain than open adrenalectomy and usually requires only an overnight hos- pital admission. It has therefore become the procedure of choice for the treatment of patients with primary hyper- aldosteronism caused by an aldosterone-secreting adenoma.
Supported in part by UCSF/Mt Zion Health Systems, San Francisco, Calif.
Presented at the 106th Scientific Session of the Western Surgical Association, Indianapolis, Ind, November 18, 1998.
We thank the endocrinologists who have helped us care for these patients: J. B. Tyrrell, MD; P. A. Fitzgerald, MD; M. Schambelan, MD; and E. G. Biglieri, MD.
Corresponding author: Quan-Yang Duh, MD, Surgi- cal Service 112, 4150 Clement St, San Francisco, CA 94121 (e-mail: Quan-Yang.Duh@med.va.gov).
REFERENCES
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3. Weigel RJ, Wells SA, Gunnells JC, Leight GS. Surgical treatment of primary hy- peraldosteronism. Ann Surg. 1994;219:347-352.
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DISCUSSION
Richard A. Prinz, MD, Chicago, Ill: I want to compliment the San Francisco group for continuing to unfold the story of the surgical management of primary hyperaldosteronism for us. This problem, when due to a small, benign unilateral adenoma, is ideally suited for laparoscopic management. The hyperten- sion that these patients have can be reversed with minimal mor- bidity and risk from the operation. The authors have con- firmed the safety and efficacy of the laparoscopic approach in comparison with open adrenalectomy. I was struck by the pa- tient demographic differences in their 2 groups.
First, it seems that the 38 open operations were accumu- lated during an 11-year period from 1975 to 1986. The lapa- roscopic patients have all been treated in the last 5 to 6 years. I wonder why there is this hiatus in between the 2 groups? Are you reporting all of the patients treated with primary hyperaldosteronism by the surgeons at UCSF? Clearly, you are seeing more patients now. I think you would have access to your referral sources to tell us if these have widened to explain the increased number of patients? Do you think that, much like laparoscopic cholecystectomy, there has been a loosening of indications for this operation in patients with suspected hyperaldosteronism? The gender and age of the 2 groups are significantly different, with the laparoscopic patients being much older and more commonly male. Is this actually the same disease that you are seeing? It is hard to explain such a change in gender and age characteristics. You would think that you would be diagnosing patients at an ear- lier age today, rather than a later age.
I would like to touch on your preoperative evaluation. Three of your laparoscopic adrenalectomy patients did not have sup- pressed plasma renin activity. This is supposed to be one of the hallmarks of this disease. I would like to know, what was the outcome in these 3 patients? Was one of these the patient that you noted as having hyperplasia? More importantly, what is your laboratory criteria for diagnosis of primary hyperaldoster- onism? Computed tomographic scanning was used through- out the study. More recently with the laparoscopic patients, 3-mm cuts were used to identify the tumor, and you did so in 39 of the 42 laparoscopically treated patients.
I would ask about the use of NP-59 scanning and selec- tive venous catheterization and how you use these studies in your current practice. Keeping in mind that as many as 2% of
patients undergoing CT scanning will have an incidental ad- renal nodule identified, do you use these functional localizing studies to rule out an incidental adrenocortical nodule and do you think that the patient who remained hypokalemic and hy- pertensive after your unilateral laparoscopic adrenalectomy ac- tually had an incidental adrenal cortical adenoma that you ini- tially removed? Both the lateral and posterior retroperitoneal approaches were used in two thirds and one third of the lapa- roscopically treated patients, respectively. I know a subse- quent paper will deal with this issue, but can you comment on the specific advantages of each approach for primary hyperal- dosteronism? I would also like to ask you why your follow-up is short for the open adrenalectomy patients. This group of- fers a unique opportunity for studying the long-term outcome in primary hyperaldosteronism, and I think it would be im- portant for you to share that with us.
Norman Thompson, MD, Ann Arbor, Mich: Mr Shen men- tioned that the first patient with an aldosteronoma was operated on at the University of Michigan. I think I am the only person in this room who actually helped to take care of that patient. That was 44 years ago when I was a medical student. She had one of the complications that you mentioned, anemia. However, her ane- mia was due to the fact that she was in the hospital for 6 months preoperatively and 1 month postoperatively and had blood drawn every day. That was before we had HMOs. Her exploration oc- curred on December 14, 1954. Jerry Conn was in attendance with William Baum, the urologist who explored her. He was the most junior attending surgeon on the urology service. Reed Nesbitt, who was chief, was not very enthusiastic at that time in this new entity that was proposed by Jerry Conn. The operation proposed was a bilateral adrenalectomy because hyperplasia was the sus- pected diagnosis. No one had ever described an aldosterone- secreting adenoma before. On exploration, a 4-cm tumor was found in the right adrenal and removed. The first paper on aldosteron- ism was published 2 months later, almost record time. It was part of Jerry Conn’s presidential address to the Society of Clinical In- vestigation given in October 1954 but included an addendum about this first patient and operation. Looking into the reason for that, the Journal of Laboratory and Clinical Medicine was edited by Wil- liam Robinson, who was chairman of the Department of Inter- nal Medicine at the University of Michigan. With that back- ground, I would like to make a few comments about this particular paper. It is very surprising that you found so many males when in most series 3 of 4 are females. It makes me wonder whether in the era before laparoscopic surgery, males were afraid to be op- erated on. Could that be the explanation?
The other point is related to early diagnosis. Again, it is hard to understand that patients with a mean age of 50 years compared with those with a mean age of 35 years would suggest earlier di- agnosis. There is some discrepancy. You make note that diagno- sis of an adenoma was established or suspected by CT scanning. Fortunately, you did point out that CT scanning might detect an incidentaloma rather than an aldosteronoma. I would warn ev- eryone that one can be misled to remove an incidentaloma on the side opposite a small adenoma. Subsequently you could end up with a bilateral adrenalectomy, which would be a real tragedy. We have emphasized the use of NP-59 scintiscanning which, inciden- tally, was also developed at the University of Michigan. We do that in every patient because we do not want to take out an adrenal that may not have the small adenoma. About 10% of patients have adenomas that are too small to be detected even by either the type of CT you are using or NP-59 scans. In those cases, I think there is a place for selective venous sampling. Dr Clark, tell us what you actually do. Are you taking a risk in not obtaining substantiating localization studies in patients who could have incidentalomas?
Steven DeJong, MD, Maywood, Ill: I have 2 brief ques- tions. Could you give us some information about operative time
and pain medication required in your patients as this experi- ence is evolving into the operation of choice or the route of choice for treating patients with surgical hypertension from excess al- dosterone production.
Did you use any other technology, such as intra-abdominal laparoscopic ultrasonography, when operating on these pa- tients? Was it helpful? These are relatively small tumors com- pared with some of the other adrenal tumors that we deal with and some have reported that this technology might be helpful.
Dr Clark: One weakness of our study is that we com- pared our laparoscopically treated patients with patients who had previously been treated by open adrenalectomy at our medi- cal center and were previously reported by Dr Robert Lim. This difference certainly contributed to the variation in patient pro- files in the 2 groups. The short-term follow-up in our open group was because no one has done a long-term outlook study in these patients. During the period we did open adrenalectomies, it was more difficult to make the diagnosis of primary hyperaldoste- ronism as assays for aldosterone and renin were not as accu- rate as they are today and localization tests were not as sensi- tive. Thus, for almost all of our initial (open) group of patients, a referring endocrinologist would send his patients to another endocrinologist at UCSF who specialized in adrenal tumors and hypertension.
Dr Prinz asked if there is a loosening of indications for lapa- roscopic adrenalectomy similar to that observed for cholecys- tectomy, and the answer we believe is yes. He also asked why the change in demographics? We are not sure. In the laparo- scopic group, 9 operations were done at the VA Medical Cen- ter in San Francisco, but this would not completely account for the predominance of men in our laparoscopic group since most endocrine diseases are more common in women. Has the disease changed? I do not think so. We make the diagnosis the same way it was done previously, that is, by documenting an increased aldosterone level in a patient with a low renin level. More postural studies were done in our open group. In pa- tients with an adrenocortical adenoma the aldosterone levels would paradoxically fall or fail to increase with standing whereas in normal patients and in those with hyperplasia, the aldoster- one levels usually increased with standing.
Dr Thompson asked a very important question regarding the possibility of an adrenal “incidentaloma” in patients with primary hyperaldosteronism. This is a real possibility since adrenal inci- dentalomas occur in about 1.5% of the population. For example, a patient with primary hyperaldosteronism could have a coexist- ing nonfunctioning adrenocortical adenoma. Our one failure in our laparoscopic group might have been prevented if we had done postural studies or adrenal vein catheterization studies for aldos- terone and cortical levels preoperatively. I would strongly recom- mend that such studies be done for any patient when hyperplasia (bilateral disease) is a possibility. Scanning with NP-59 might also be useful in such patients as suggested by Dr Norman Thompson, but we have limited experience with this study.
In this retrospective study, we did not compare duration of hospitalization, postoperative pain, or time taken to return to work. These data have been reported by others and after lapa- roscopic adrenalectomy, patients can be hospitalized for a shorter time, experience less pain, and return to work sooner. How- ever, after an open Hugh-Young (posterior) approach, most pa- tients could also go home within 24 hours.
Dr DeJong, our duration of operation was initially about 3 hours, but now takes less time. These procedures are done with our sur- gical residents and most have been directed by Dr Siperstein and Dr Duh. Intraoperative ultrasound is quite useful, especially in some of the heavier patients. Most adrenocortical adenomas that cause primary hyperaldosteronism are small (<2-cm) tumors. Intraop- erative ultrasound certainly helps identify these tumors.