STEROID CONTENT OF THE PERIPHERAL AND ADRENAL VEIN IN CUSHING’S SYNDROME DUE TO ADRENOCORTICAL ADENOMA AND CARCINOMA
ALICE C. LEVINE, HAROLD A. MITTY AND J. LESTER GABRILOVE
From the Endocrine Division of the Bronfman Department of Medicine and Department of Radiology, Mount Sinai Hospital and School of Medicine of the City University of New York, New York, New York
ABSTRACT
Selective adrenal vein catheterization was done preoperatively in 11 patients with Cushing’s syndrome owing to either an adrenal adenoma (6) or an adrenal carcinoma (5). Peripheral and adrenal venous blood (tumor side) was analyzed for progesterone, 17-hydroxyprogesterone, testos- terone, delta-4-androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, cortisol and 11-deoxycortisol. Comparisons were made of the ratios of precursors to products in the androgen and cortisol production pathways.
In adrenal vein samples, cortisol levels were higher in the adenoma patients (p equals 0.06). These patients had a higher ratio of 17-hydroxyprogesterone to delta-4-androstenedione (p less than 0.04). The ratio of 11-deoxycortisol to cortisol was higher in the carcinoma patients (p less than 0.02).
In the peripheral samples, the carcinoma patients had higher levels of testosterone and 11- deoxycortisol (p less than 0.02) and progesterone (p equals 0.05). The most striking differences were in the peripheral levels of 17-hydroxyprogesterone, delta-4-androstenedione and dehydroepiandros- terone, which were 10 to 20 times higher in the carcinoma group (p less than 0.005). The ratios of progesterone to 17-hydroxyprogesterone and 17-hydroxyprogesterone to 11-deoxycortisol were higher in the adenoma group (p less than 0.005 and p equals 0.06, respectively). The peripheral blood ratio of 11-deoxycortisol to cortisol was higher in the carcinoma group (p less than 0.03).
These data indicate that peripheral and adrenal venous steroid levels and ratios of precursors to products are significantly different in the 2 groups. The carcinomas have a block in the conversion of 11-deoxycortisol to cortisol with a subsequent accumulation in androgen and cortisol precursors. The elevations in 17-hydroxyprogesterone, delta-4-androstenedione and dehydroepiandrosterone, and in the the ratio of 11-deoxycortisol to cortisol in the carcinoma group are most striking in the periphery. Peripheral blood steroid measurement in patients with Cushing’s syndrome and an adrenal mass aids in the preoperative differentiation of carcinoma from adenoma. (J. Urol., 140: 11-15, 1988)
In previous studies from this laboratory we reported on the steroid content of the adrenal venous effluent in tumors of patients with virilizing adrenal tumors1 and patients with pri- mary aldosteronism.2 In this study we report on the steroid content of the adrenal venous effluent in patients with Cushing’s syndrome who subsequently had either an adrenal adenoma or adrenal carcinoma on surgical pathological studies. The investigation was done in an attempt to afford further diagnostic clues to differentiate the 2 entities clinically (pre- operatively) and to provide further data for testing our com- puter model of adrenocortical function.3
We have previously reported on the use of the steroid content of peripheral plasma to differentiate adrenocortical adenoma from adrenocortical carcinoma in the presence of Cushing’s syndrome.4 Our study augments this latter report using addi- tional case material.
MATERIALS AND METHODS
Five women with adrenocortical carcinoma and 6 patients with adrenocortical adenoma (5 women and 1 man) were stud- ied. Clinical information on the patients is provided in table 1. Plasma cortisol values given in table 1 were determined in the
Accepted for publication November 17, 1987.
Supported by Grants in Aid from Edmond de Rothschild Foundation, Murray M. Rosenberg, Mrs. Meyer Willett, Jack Martin Fund, Mr. Milton Petrie, Arthur R. Sohval Research Fund and Grant RR-71 from the Division of Research Resources, National Institutes of Health.
routine laboratory with a standard kit assay that does not separate cortisol from 11-deoxycortisol. All procedures were done by selective adrenal vein catheterization as part of the diagnostic investigation several days before definitive surgical therapy. Blood samples were taken from the periphery and from the adrenal veins (tumor side).
Measurement of progesterone, 17a-hydroxyprogesterone, testosterone, 44-androstenedione, dehydroepiandrosterone and dehydroepiandrosterone sulfate were done by previously re- ported methods using specific radioimmunoassay.5 Cortisol and 11-deoxycortisol were measured after chromatographic sepa- ration by competitive protein binding.6-8 Statistical analysis of the results was done with the Wilcoxon nonpaired rank sum test.
RESULTS
Absolute values obtained from the adrenal venous effluent on the side of the tumors in both groups of patients are shown in table 2. The mean and median values for progesterone, 17- hydroxyprogesterone and cortisol were higher in the adenoma patients. The mean and median values for testosterone, 44- androstenedione, dehydroepiandrosterone and 11-deoxycortisol were higher in the carcinoma group. The difference in the cortisol values between the 2 groups reached borderline statis- tical significance (p = 0.06). However, the differences in the other absolute values did not reach statistical significance, possibly because of the pulsatile nature of adrenal steroidogen-
esis as well as the small sample size and the large variance within groups. Although measurements of dehydroepiandros- terone sulfate were not done in all subjects, the adenoma patients clearly had lower values than the carcinoma patients.
The peripheral venous steroid levels in the same patients are shown in table 3. In the periphery the mean and median values for testosterone, 11-deoxycortisol and progesterone were higher in the carcinoma patients (p <0.02, p <0.02 and p = 0.05, respectively).
The most striking differences, however, were in the values for 17-hydroxyprogesterone, 44-androstenedione and dehydro- epiandrosterone, which were 10 to 20 times higher in the carcinoma group with remarkable significance statistically (p <0.005). Of note, the only absolute value in the periphery that was not higher in the carcinoma patients was that of cortisol.
Table 4 shows the ratios of precursors to products in the androgen and cortisol production pathways from the adrenal vein samples of the adenoma versus the carcinoma group. The ratio of 17-hydroxyprogesterone to 44-androstenedione was
| Pt. Age No .- (yrs.)-Sex | Site and Size of Tumor | Metastases | Urinary Free Cortisol* (mcg./24 hrs.) | Plasma Cortisolt (mcg./dl., a.m.) |
|---|---|---|---|---|
| Adenoma | ||||
| 1-26-F | Lt., 3 cm. | - | >618 | 25.5 |
| 2-32-F | Lt., 3 cm. | - | 1,021 | 24.0 |
| 3-21-F | Rt., 4 x 3 cm. | - | 297 | 21.0 |
| 4-68-F | Lt., 3 cm. | - | 311 | 23.5 |
| 5 -- 50-F | Rt., 3 cm. | - | 238 | 25.9 |
| 6-63 -- M | Lt., 3.5 cm. | - | 183 | 26.3 |
| Ca | ||||
| 7-56-F | Rt., 9 cm. | Liver, lung | 176-310 | 45 |
| 8 -- 71-F | Lt. flank mass | Liver, lung | 256 | 44 |
| 9-25-F | Lt., 10 x 11 × 6 cm. | - | 912 | 37.5 |
| 10-73-F | Rt., 17.5 cm. | - | >225 | 32.5 |
| 11-29-F | Lt. flank mass | Liver, lung | 1,395 | 59.9 |
* Normal 20 to 100 mcg./dl.
t Normal 10 to 25 mcg./dl.
statistically higher in the adenomas (p = 0.03). There was a highly significant difference as well in the ratio of 11-deoxy- cortisol to cortisol, this value being higher in the carcinoma group (p <0.02).
Table 5 shows these ratios from the peripheral vein samples in the 2 groups. The ratio of 11-deoxycortisol to cortisol was again significantly higher in the carcinoma group (p = 0.02). The ratio of progesterone to 17-hydroxyprogesterone was sig- nificantly higher in the adenoma group (p = 0.004). The ratio of 17-hydroxyprogesterone to 11-deoxycortisol was higher in the adenoma group with borderline significance statistically (p = 0.06).
DISCUSSION
In patients with Cushing’s syndrome and an adrenal mass the clinical distinction between adrenocortical adenoma and carcinoma is often difficult to establish. Because the prognosis of the 2 disorders is widely different, many attempts have been made to find a means to differentiate adrenocortical adenoma from carcinoma. Histologically, the generally accepted criteria of malignancy may be of limited value in assessing adrenocor- tical neoplasia.9 Clinically, carcinoma is suspected when the adrenal mass is greater than 5 cm. in diameter in at least 1 dimension.1º However, in a large study of adrenocortical tumors neither small tumor size nor benign histological features were sufficient to predict benign clinical behavior.11
It has been demonstrated previously that carcinomas have a block in the conversion of 11-deoxycortisol to cortisol as evi- denced by high urinary titers of tetrahydro-11-deoxycortisol in patients with adrenocortical carcinoma.12 In previous studies from our laboratory measuring secretory rates of 11-deoxycor- tisol and cortisol, we have shown that the ratio of cortisol to 11-deoxycortisol in 2 patients with adrenocortical carcinoma was reduced.13 There have been additional reports of high secretory rates of deoxycorticosterone in adrenocortical carci- nomas, indicating that the carcinomas have a widespread block in the 11-hydroxylase enzyme, which converts 11-deoxycortisol to cortisol and deoxycorticosterone to corticosterone.14-16
Studies on normal and hypercortisolemic subjects have shown that there is a variability in baseline adrenal vein cortisols in normal and pathological states, probably owing to the pulsatile nature of adrenal steroidogenesis.17, 18 Peripheral cortisol levels in patients with Cushing’s syndrome of different
| Pt. No. | Progesterone | 17-Hydroxy- progesterone | Testosterone | 44-Andros- tenedione | Dehydroepi- androsterone* | Dehydroepi- androsterone- Sulfate* | Cortisol* | 11-Deoxycortisol* |
|---|---|---|---|---|---|---|---|---|
| Adenoma | ||||||||
| 1 | 474 | 2,987 | 63 | 2,841 | 244 | 85.6 | 10.6 | |
| 2 | 162 | 1,771 | 1,921 | 1,718 | ||||
| 3 | 404 | 2,820 | 213 | 10,941 | 929 | 350 | 13.0 | |
| 4 | 35 | 80 | 13 | 31 | 61 | 8 | 14.9 | 0.35 |
| 5 | 2,400 | 4,329 | 1,010 | 2,508 | 856 | 19 | 242 | 8.4 |
| 6 (male pt.) | 986 | 4,482 | 244 | 14,286 | 3,077 | 450 | 377 | 19.1 |
| Mean ± standard deviation | 744 ± 875 | 2,744 ± 1,652 | 309 ± 404 | 5,421 ± 5,753 | 1,148 ± 1,112 | 214 ± 160 | 10.2 ±68 | |
| Median | 439 | 2,905 | 213 | 2,675 | 893 | 242 | 10.6 | |
| Ca | ||||||||
| 1 | 200 | 5,877 | 1,104 | 25,000 | 12,116 | 10 | 31.5 | |
| 2 | 202 | 1,046 | 1,521 | 3,012 | 2,075 | |||
| 3 | 72 | 585 | 467 | 2,258 | 1,102 | 5.3 | 1.9 | |
| 4 | 290 | 2,352 | 430 | 11,061 | 626 | 770 | 68.2 | 51.7 |
| 5 | 70 | 218 | 50 | 1,472 | 1,190 | 660 | 17.1 | 4.0 |
| Mean ± standard deviation | 167 ± 95 | 2,016 ± 2,304 | 714 ± 589 | 8,560 ± 9,966 | 3,422 ± 4,888 | 25.1 ± 29.1 | 22.3 ± 23.8 | |
| Median | 200 | 1,046 | 467 | 3,012 | 1,190 | 13.6 | 17.8 | |
| p valuet | 0.2 | 0.5 | 0.2 | 0.6 | 0.3 | 0.06 | 0.7 |
* Values are reported as mcg./dl. All other values are reported as ng./dl.
t Wilcoxon nonpaired rank sum test.
| Pt. No. | Progesterone | 17-Hydroxy- progesterone | Testosterone | A4-Andros- tenedione | Dehydroepi- androsterone* | Dehydroepi- androsterone- Sulfate* | Cortisol* | 11-Deoxycorti- sol* |
|---|---|---|---|---|---|---|---|---|
| Adenoma | ||||||||
| 1 | 107 | 185 | 16 | 175 | 75 | 16 | 0.17 | |
| 2 | 32 | 42 | 14 | 133 | 127 | |||
| 3 | 13 | 31 | 33 | 142 | 37 | 16.6 | 0.07 | |
| 4 | 38 | 21 | 9 | 89 | 21 | 9.4 | 0.07 | |
| 5 | 59 | 48 | 67 | 98 | 48 | 11 | 0.39 | |
| 6 (male pt.) | 34 | 76 | 110 | 119 | 127 | 350 | 24.9 | 0.49 |
| Mean + standard deviation | 47 ± 33 | 67 ±61 | 42 ± 40 | 126 ± 31 | 73 ± 46 | 15.5 ± 6 | 0.2 ± 0.19 | |
| Median | 36 | 45 | 25 | 126 | 62 | 16 | 0.17 | |
| Ca | ||||||||
| 1 | 99 | 1,343 | 873 | 7,500 | 3,942 | 9.6 | 12.85 | |
| 2 | 159 | 577 | 1,057 | 1,604 | 1,341 | |||
| 3 | 41 | 568 | 441 | 2,142 | 682 | 5 | 2.7 | |
| 4 | 142 | 474 | 430 | 3,438 | 519 | 745 | 9.2 | 15.0 |
| 5 | 97 | 233 | 59 | 2,278 | 1,188 | 720 | 26.2 | 4.5 |
| Mean ± standard deviation | 108 ± 45.9 | 639 ± 417 | 572 ± 396 | 3,392 ± 2,392 | 1,534 ± 1,388 | 12.5 ± 9.4 | 8.7 ± 6.1 | |
| Median | 99 | 568 | 441 | 2,278 | 1,188 | 9.4 | 8.7 | |
| p valuet | 0.05 | 0.004 | 0.018 | 0.004 | 0.004 | 0.4 | 0.016 | |
| Normal values | ||||||||
| Female pt. | 20-90 | 20-80 | <100 | 90-280 | 140-850 | 80-335 | 6.1-12.1 | 0.05-0.07 |
| (nonluteal) | (nonluteal) | (mean 9.1 ± 3) | ||||||
| Male pt. | 13-100 | 20-180 | 300-1,000 | 80-200 | 83-1,040 | 200-335 | 6.1-12.1 | 0.05-0.07 |
* Values are reported as mcg./dl. All other values are reported as ng./dl.
t Wilcoxon nonpaired rank sum test.
| Pt. No. | Progesterone/ 17-Hydroxy- progesterone | 17-Hydroxy- progesterone/ 11-Deoxycortisol | 11-Deoxycortisol/ Cortisol | 17-Hydroxy- progesterone/ 44-Androstenedione | Dehydroepi- androsterone/ 44- Androstenedione | 44-Androstenedione/ Testosterone |
|---|---|---|---|---|---|---|
| Adenoma | ||||||
| 1 | 0.159 | 0.282 | 0.129 | 1.05 | 0.086 | 45.0 |
| 2 | 0.091 | 0.922 | 0.894 | |||
| 3 | 0.143 | 0.217 | 0.037 | 0.258 | 0.085 | 51.3 |
| 4 | 0.44 | 0.23 | 0.02 | 2.6 | 2.0 | 2.4 |
| 5 | 0.554 | 0.52 | 0.04 | 1.73 | 0.341 | 2.48 |
| 6 (male pt.) | 0.220 | 0.235 | 0.051 | 0.314 | 0.215 | 58.5 |
| Mean ± standard de- viation | 0.268 ± 0.185 | 0.30 ± 0.13 | 0.05 ± 0.04 | 1.1 ± 0.89 | 0.60 ± 0.74 | 32 ± 27 |
| Median | 0.189 | 0.23 | 0.04 | 0.99 | 0.28 | 45 |
| Ca | ||||||
| 1 | 0.034 | 0.187 | 3.20 | 0.235 | 0.485 | 22.6 |
| 2 | 0.193 | 0.347 | 0.689 | 1.98 | ||
| 3 | 0.12 | 0.31 | 0.36 | 0.259 | 0.488 | 4.84 |
| 4 | 0.123 | 0.045 | 0.758 | 0.213 | 0.057 | 25.7 |
| 5 | 0.32 | 0.06 | 0.23 | 0.148 | 0.808 | 29.0 |
| Mean + standard de- viation | 0.16 ± 0.11 | 0.15 ± 0.12 | 1.1 ± 1.4 | 0.240 ± 0.073 | 0.505 ± 0.286 | 16.9 ± 12.6 |
| Median | 0.12 | 0.12 | 0.56 | 0.235 | 0.488 | 22.6 |
| p value* | 0.3 | 0.19 | 0.016 | 0.03 | 0.9 | 0.4 |
* Wilcoxon nonpaired rank sum test.
etiologies have been shown as well to have numerous secretory bursts during a 24-hour period, although it is agreed that the normal diurnal rhythm is abolished.19
In a study of women with idiopathic hirsuitism, adrenal vein effluent samples were analyzed for cortisol, testosterone, 44- androstenedione and aldosterone levels.2º This study demon- strated that the 19 carbon steroid secretion (44-androstenedi- one and testosterone) paralleled that of cortisol, both in the basal state and after adrenocorticotropic hormone stimulation. In contrast, aldosterone secretion was independent of cortisol.
Because of the evidence that adrenal steroid secretion is pulsatile in the normal and pathological states, we have re- ported not only on the absolute steroid values but on the ratios of precursors to products in the androgen and cortisol produc- tion pathways in our 2 groups of patients. These ratios should remain constant regardless of sampling times or intervals.
In our study, encompassing more subjects than our previous report, we compared the absolute steroid levels and the ratios of precursors to products in the adrenal venous effluent and peripheral veins. These investigations indicate that the levels
RIGHTS LINKY
4
| Pt. No. | Progesterone/ 17-Hydroxyprogesterone | 17-Hydroxyprogesterone/ 11-Deoxycortisol | 11-Deoxycortisol/ Cortisol | 17-Hydroxyprogesterone/ 44-Androstenedione | Dehydroepiandrosterone/ 44-Androstenedione | 44- Androstenedione/ Testosterone |
|---|---|---|---|---|---|---|
| Adenoma | ||||||
| 1 | 0.578 | 1.1 | 0.01 | 1.06 | 0.43 | 11.0 |
| 2 | 0.76 | 32 | 0.955 | 9.5 | ||
| 3 | 0.42 | 0.44 | 0.004 | 0.22 | 0.26 | 4.3 |
| 4 | 1.8 | 0.30 | 0.007 | 0.24 | 0.24 | 9.9 |
| 5 | 1.2 | 0.12 | 0.040 | 0.49 | 0.49 | 1.5 |
| 6 (male pt.) | 0.45 | 0.16 | 0.020 | 0.64 | 1.07 | 1.08 |
| Mean + standard deviation | 0.85 ± 0.55 | 0.42 ± 0.39 | 0.02 ± 0.01 | 0.49 ± 0.32 | 0.57 ± 0.35 | 6.2 ± 4.4 |
| Median | 0.67 | 0.30 | 0.01 | 0.40 | 0.46 | 6.9 |
| Ca | ||||||
| 1 | 0.07 | 0.104 | 1.3 | 0.179 | 0.526 | 8.59 |
| 2 | 0.276 | 0.360 | 0.836 | 1.52 | ||
| 3 | 0.07 | 0.21 | 0.5 | 0.265 | 0.318 | 4.86 |
| 4 | 0.30 | 0.03 | 1.6 | 0.138 | 0.151 | 8.0 |
| 5 | 0.42 | 0.05 | 0.17 | 0.102 | 0.522 | 39.0 |
| Mean ± standard deviation | 0.23 ± 0.15 | 0.10 ± 0.08 | 0.92 ± 0.68 | 0.209 ± 0.104 | 0.47 ± 0.26 | 12.0 ± 14.0 |
| Median | 0.28 | 0.08 | 0.94 | 0.179 | 0.52 | 8.0 |
| p value* | 0.004 | 0.064 | 0.016 | 0.08 | 0.9 | 0.8 |
* Wilcoxon nonpaired rank sum test.
of testosterone, 44-androstenedione, dehydroepiandrosterone and 11-deoxycortisol in the peripheral samples are higher in the carcinoma group.
In the past urinary determinations of the neutral 17-ketoste- roids were done to differentiate adrenal adenoma from adrenal carcinoma in patients with Cushing’s syndrome. However, al- though the values generally were reduced or normal in the patients with adenomas, increases in the urinary excretion of the 17-ketosteroids occurred in 13 per cent of the patients with adenoma in 1 report, while 75 per cent of the patients with adrenocortical carcinoma exhibited significant increases.21 Since the bulk of the neutral 17-ketosteroids probably repre- sents metabolism of serum dehydroepiandrosterone sulfate, similar findings might be expected in patients with Cushing’s syndrome in whom dehydroepiandrosterone sulfate is meas- ured. In a study comparing dehydroepiandrosterone sulfate values from patients with Cushing’s syndrome owing to adrenal adenoma versus bilateral adrenal hyperplasia, Yamaji and as- sociates found that the dehydroepiandrosterone sulfate values were much lower in the adenoma group, ranging from less than 5 to 36 mcg./dl. in the 28 patients with adrenal adenoma.22 Their report did not include any patients with adrenal carci- noma. However, they state without presenting data that pa- tients with adrenocortical carcinoma may have extremely high serum dehydroepiandrosterone sulfate concentrations. In our study the adenoma patients clearly have lower dehydroepian- drosterone sulfate values than the carcinoma patients. How- ever, the man with an adenoma had a high value in the periphery (350 mcg./dl.) and in the adrenal vein (450 mcg./dl.), well above the values obtained in the adenoma group in the study of Yamaji and associates.
In addition, the ratio of progesterone to 17-hydroxyproges- terone in the periphery and the ratio of 17-hydroxyprogesterone to 44-androstenedione in the adrenal veins were higher in the adenoma group. The ratio of 11-deoxycortisol to cortisol clearly was higher in the carcinoma patients in the peripheral and adrenal venous samples.
In carcinoma there is a partial block in the conversion of 11- deoxycortisol to cortisol. This is reflected in the adrenal venous effluent as well as in the peripheral samples, and secondarily in the peripheral blood by the higher levels of steroid precur- sors, specifically progesterone, 17-hydroxyprogesterone, 44-an- drostenedione, testosterone and dehydroepiandrosterone in the
carcinoma group. The fact that these differences between the 2 groups are more evident in the periphery than in the adrenal veins may be explained perhaps by the observation that the venous drainage from a large carcinoma generally is far greater than that from a relatively small adrenocortical adenoma. Con- sequently, modest concentration differences between the 2 groups in adrenal steroid secretion are magnified in the periph- eral samples as the result of the large difference in the bolus (concentration times blood flow) being delivered to the periph- ery in carcinomas versus adenomas. This exaggeration of dif- ferences between the 2 groups in peripheral samples is fortui- tous, since peripheral blood samples are obtained much more readily than adrenal venous samples.
Thus, biochemical testing of peripheral blood samples can be used to distinguish adrenocortical carcinomas from adenomas preoperatively. The most striking finding is marked elevation in peripheral levels of 17-hydroxyprogesterone, 44-androstene- dione and dehydroepiandrosterone in the carcinoma group com- pared to the adenoma group. An elevation in any of these 3 compounds in the peripheral blood, coupled with an elevation of peripheral 11-deoxycortisol and a high ratio of 11-deoxycor- tisol to cortisol in a cushingoid patient with an adrenal mass is highly suspicious of carcinoma.
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