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Biomedical subjects

W F Young

Publications and source records attributed to W F Young.

At least 91 records · Page 5Linked to original sources
PubMed1994

Aqueous flow in humans after adrenalectomy.

PURPOSE: This study was performed to determine if the circadian rhythm of aqueous humor formation and the aqueous humor suppressing effect of beta-adrenergic antagonists can occur in the absence of adrenally derived epinephrine. METHODS: Twenty-one human subjects who had undergone bilateral adrenalectomy were studied during a 28-hour period. The study was divided into four time periods as follows: morning 1 (8 AM to noon), afternoon (noon to 4 PM), night (midnight to 6 AM), and morning 2 (8 AM to noon). At 6:45 AM before the morning 2 measurements, one drop of 0.5% timolol was applied to one eye and one drop of placebo (artificial tears) was applied to the other eye. Topical fluorescein and a scanning fluorophotometer were used to measure the rate of aqueous humor flow. Twenty normal controls were studied in a similar fashion but did not undergo the morning 2 measurement. RESULTS: In the subjects lacking adrenals, the daytime rates of aqueous flow were 3.17 +/- 0.78 microliters/min (mean +/- SD) and 3.16 +/- 0.67 microliters/min for the morning 1 and afternoon periods, respectively. The rates in daytime periods were not significantly different from each other (P = 0.699). The rate of aqueous flow for the night period was 1.37 +/- 0.37 microliters/min, a 57% reduction from both morning 1 and afternoon periods (P < 0.001). The morning, afternoon, and night rates of flow in normal controls were not significantly different from the rates in subjects lacking adrenals. For the morning 2 period, the aqueous flow was 2.74 +/- 0.54 microliters/min for the placebo-treated eye and 1.77 +/- 0.38 microliters/min for the timolol-treated eye. The rate of aqueous flow was reduced (35%) in the timolol-treated eye when compared to the fellow placebo-treated eye (P < 0.001). The timolol-treated eye also showed a 26% reduction in intraocular pressure when compared to the fellow placebo-treated eye (P < 0.001). CONCLUSION: The study demonstrates that both the circadian rhythm of aqueous flow and the daytime response to timolol persist in the absence of the adrenal glands.

Adrenalectomy↗
PubMed1994

The effect of oral dexamethasone on the circadian rhythm of aqueous humor flow in humans.

PURPOSE: To determine if the circadian rhythm of plasma corticosteroid activity is necessary for the circadian rhythm of aqueous humor flow to occur in humans. METHODS: Twenty normal volunteers were recruited for this randomized, double-masked, placebo-controlled study. Oral dexamethasone was given at a dose of 0.5 mg every 6 hours; this is equivalent to more than two times the normal 24-hour endogenous adrenal corticosteroid production. This dosage schedule will maintain a relatively constant level of corticosteroid action throughout a 24-hour period. Topical fluorescein and a scanning fluorophotometer were used to measure the rate of aqueous humor flow. Subjects were studied on two separate days. On one study day, the subject took 0.5 mg of dexamethasone every 6 hours; on the other study day, the same subject took a placebo every 6 hours. RESULTS: During the morning, aqueous flow was 4.06 +/- 0.70 microliters/min (mean +/- SD) in subjects taking dexamethasone and 3.82 +/- 0.85 in subjects taking a placebo. This 6% higher dexamethasone flow was not significant (P = 0.10). During the afternoon, aqueous flow was 3.83 +/- 0.78 in subjects taking dexamethasone and 3.52 +/- 0.77 in subjects taking a placebo. This 9% higher dexamethasone flow was statistically significant (P = 0.02). The nighttime aqueous flow was 1.38 +/- 0.45 in subjects taking dexamethasone and 1.43 +/- 0.34 in subjects taking the placebo. There was not a significant difference between placebo and dexamethasone during the night (P = 0.40). On each day, intraocular pressure was measured at 8:00 AM, 4:00 PM, and 6:00 AM. When comparing dexamethasone to placebo, no significant difference was observed in any of the intraocular pressures. CONCLUSIONS: The study is interpreted as showing that the reduction of aqueous humor flow during sleep can occur in the absence of a comparable fall in plasma corticosteroid pathway.

Administration, Oral↗
PubMed1993

Hypertension and dyslipidemia in patients with insulinoma.

Hyperinsulinemia is alleged to contribute to the pathogenesis of hypertension and dyslipidemia (hypertriglyceridemia) in the setting of insulin resistance. To assess the association among hyperinsulinemia, hypertension, and hypertriglyceridemia in the absence of insulin resistance, we determined their prevalence in a large cohort of patients with insulinoma (N = 250). In this retrospective case-control study, patients with insulinoma were matched by age, gender, race, and year of operation with 217 control patients admitted to the hospital for elective cholecystectomy. Mean preoperative blood pressure measurements were compared between study patients and control patients. In addition, age-, gender-, and race-specific percentiles of blood pressure were compared with data from the National Health and Nutrition Examination Survey I, and those of triglycerides (N = 65) and cholesterol (N = 70) were compared with Mayo Clinic normal reference data. The study group consisted of 105 men and 145 women; the median age was 41 years (range, 8 to 82). The median duration of symptoms before operation was 1.9 years (range, 0.05 to 40 years). After adjustment for body mass index, no statistically significant differences in systolic and diastolic blood pressure were noted between patients with insulinoma and matched control patients (131 +/- 19 versus 128 +/- 18 mm Hg and 81 +/- 11 versus 79 +/- 9 mm Hg, respectively). No relationship was observed between duration of hyperinsulinemia (as long as 40 years) and blood pressure. The age- and gender-specific percentiles of systolic and diastolic blood pressure of the patients with insulinoma did not differ from the age- and gender-specific percentiles for the general white population.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Aging and the human pituitary gland.

Pituitary glands obtained at autopsy from 41 men (90 to 97 years old) and 45 women (90 to 98 years old) were studied histologically and immunohistochemically to determine the age-related alterations. Pituitaries from patients 30 to 39 years old (48 cases) and 60 to 89 years old (187 cases) were also studied and served as controls. Interstitial, perivascular fibrosis was seen in 88% of the aged adenohypophyses and, although significantly more intense than that in those of the fourth decade of life (P < 0.001), was similar to that noted in those of the seventh to ninth decades. Pituitaries of men were significantly more fibrotic than were those of women (P < 0.05). In proportion to the extent of fibrosis, the number of somatotrophs decreased in the lateral wings, whereas other cell types did not change quantitatively. Small deposits of amyloid and of iron were detected in seven and three cases, respectively. Squamous metaplasia in cells of the pars tuberalis was noted in 29%. The incidence of "basophil invasion" (the presence of corticotrophs in the posterior lobe) was 30%, a figure similar to that in younger controls. Granular cell tumorlets were detected in four aged neurohypophyses (5%), a frequency similar to that in control glands. Pituitary adenomas (two null cell, two lactotroph, and one corticotroph adenomas) were found of three men and two women in the study group. This 9% incidence of adenomas did not differ from that observed in the fourth decade (8%) or seventh decade (10%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1993

Evaluation of gastric emptying using radionuclides: gastric lavage versus ipecac-induced emesis.

STUDY OBJECTIVES: To compare the efficacy of gastric lavage and ipecac-induced emesis by using a radionuclide marker in a simulated overdose and to determine the amount of material recoverable after lavage fluid appears clear. DESIGN: Case-control, prospective cross-over study. SETTING: Nuclear medicine department of Valley Medical Center, Fresno, California. TYPE OF PARTICIPANTS: Fourteen male and five nonpregnant female adult volunteers with no pre-existing gastrointestinal disease and no medication use. INTERVENTIONS AND MEASUREMENTS: In phase 1, each volunteer ingested 30 capsules labeled with a measured amount of Tc99m with 75 mL H2O followed in five minutes by ipecac-induced emesis. In phase 2, two to four weeks later, each subject was lavaged after ingesting 30 labeled capsules. After lavage appeared clear, a 1,000-mL supplemental lavage was done and analyzed separately. All emesis or gastric lavage fluid was collected and measured for tracer activity. RESULTS: All subjects in the ipecac group vomited with an average time from ipecac to emesis of 19 minutes. Two subjects withdrew from the study, refusing to complete lavage due to discomfort. Based on retrieved material, ipecac-induced emesis returned significantly more tracer (mean +/- SD, 54.1 +/- 21.3%) than lavage until clear (mean +/- SD, 30.3 +/- 17.4%) (P = .0021). Supplemental lavage returned 12.9% of the total recovered marker (SD, 11.6%). The total of initial and supplemental returns from lavage was 35.5% (SD, 21.0%). This return was significantly less than that returned by ipecac-induced emesis (P = .016). CONCLUSION: In this study, ipecac-induced emesis was significantly more effective than gastric lavage in emptying the stomach after simulated overdose. Significant amounts of ingested material are recoverable in gastric lavage return after it appears clear.

Adult↗
PubMed1993

Spontaneous migration of an intracranial bullet into the cervical canal.

We have reported a case of intracranial to intraspinal migration of a retained bullet fragment over a course of approximately 4 years. The patient remained asymptomatic. The bullet was removed via a posterior cervical laminectomy. Migration of bullet fragments, though rare, should be included as one of the delayed complications of gunshot wound to the head.

Adult↗
PubMed1993

An early comparative analysis of the use of fibular allograft versus autologous iliac crest graft for interbody fusion after anterior cervical discectomy.

During a 2-year period (1988-1989), 23 cases of anterior cervical discectomy were performed with cadaveric fibular allograft instead of autologous iliac crest graft. The mean age of the patients was 35 years. There were 10 men and 13 women. In most cases, a one-level fusion was performed at the C5-6 level. The Smith-Robinson technique was used for discectomy and fusion, for both one- and two-level fusions. Evidence of radiographic fusion was achieved in 92% of the cases. Twenty-five cases of anterior cervical discectomy in which autologous iliac crest graft was used (1987-1988) were examined retrospectively for comparison. The mean duration of hospital stay was less in the allograft group (5.4 days vs. 7.25 days). In addition, postoperative pain was less in the allograft group because the allograft group did not have pain from the donor site. In conclusion, the use of fibular allograft for interbody fusion after anterior cervical discectomy can be performed with acceptable rates of fusion and less postoperative pain, as compared to the use of autologous iliac crest graft.

Adult↗
PubMed1993

Congenital gigantism due to growth hormone-releasing hormone excess and pituitary hyperplasia with adenomatous transformation.

The cause of gigantism in most patients is a GH-secreting pituitary tumor. In this report, a case of congenital gigantism due to probable central hypersection of GH-releasing hormone (GHRH) is described. Normal at birth (4.4 kg; 53 cm), our 7-yr-old male patient grew progressively thereafter to attain a height of 182 cm and a weight of 99.4 kg at the time of our evaluation. The markedly increased baseline plasma levels of GH (730 micrograms/L) did not suppress during a standard 3-h oral glucose tolerance test, but did increase 54% after iv infusion of GHRH. Baseline plasma levels of insulin-like growth factor-I, PRL, and immunoreactive GHRH were also markedly increased. Computed imaging of the head showed a large, partially cystic sellar and suprasellar mass. Extensive imaging studies did not localize a potential source of GHRH. Preoperative treatment with octreotide and bromocriptine for 4 months resulted in a 25% reduction of suprasellar tissue mass. The pituitary tissue removed at transsphenoidal and transfrontal operations showed massive somatotroph, lactotroph, and mammosomatotroph hyperplasia. Areas of GH- and PRL-secreting cell adenomatous transformation were also evident. No histological or immunohistochemical evidence of a pituitary source of GHRH was found. The peripheral plasma immunoreactive GHRH concentration remained unaffected by pharmacological and surgical interventions. We suspect that a congenital hypothalamic regulatory defect may be responsible for the GHRH excess in this case.

Adenoma↗
PubMed1993

Assessment of the human risk associated with the presence of carcinogenic compounds in drinking water.

Both organic and inorganic contaminants which have been implicated in causing cancer in man or, more commonly, in laboratory animals can be found in drinking water. Apart from arsenic there are none for which there is convincing epidemiological evidence of a significant risk to man. However environmental epidemiology is fraught with difficulties. There are also difficulties in interpreting laboratory animal data and extrapolating this to the low concentrations found in drinking water although mathematical models can be very useful if used sensibly. There is a danger that the rather extreme public perception of cancer could lead to over regulation of some contaminants in water, possibly with an increase in risk from other hazards such as microbiological contamination.

Animals↗
PubMed1992

Octreotide treatment of acromegaly. A randomized, multicenter study.

OBJECTIVE: To determine the effects of the somatostatin analog, octreotide acetate, in patients with acromegaly. DESIGN: Double-blind, randomized trial. SETTING: Fourteen university-affiliated medical centers. PATIENTS: One hundred fifteen acromegalic patients, 70% of whom had persistent disease after pituitary surgery or radiotherapy. INTERVENTION: Subcutaneous octreotide, 100 micrograms, or placebo every 8 hours for 4 weeks. Four weeks after the end of treatment, patients were randomized to receive 100 or 250 micrograms octreotide subcutaneously every 8 hours for 6 months. RESULTS: After 2 weeks of treatment, a single 100-micrograms injection reduced mean serum growth hormone (GH) to 30% of the pretreatment concentration within 2 hours. The integrated mean GH level was reduced over 8 hours from 39 +/- 11 micrograms/L to 9 +/- 2 micrograms/L (P less than 0.001). Mean plasma insulin-like growth factor-1 (IGF-1) was reduced from 5100 +/- 400 U/L to 2400 +/- 400 U/L (P less than 0.001). After 6 months, the mean GH was reduced from 39 +/- 13 to 15 +/- 4 micrograms/L by 300 micrograms of octreotide and from 29 +/- 5 micrograms/L to 9 +/- 2 micrograms/L by 750 micrograms of octreotide daily. The mean IGF-1 concentration was suppressed to 2100 +/- 300 and 2500 +/- 400 U/L after 300 and 750 micrograms octreotide, respectively. Integrated mean GH levels were reduced to < 5 micrograms/L in 53% (95% CI, 39% to 67%) and 49% (CI, 35% to 63%), and IGF-1 levels were normal in 68% (CI, 54% to 82%) and 55% (CI, 40% to 70%) of patients receiving low- and high-dose octreotide, respectively. A substantial decrease in headache, amount of perspiration, joint pain, and finger circumference occurred in two thirds of the patients. The pituitary size was reduced in 19% (CI, 5% to 33%) and 37% (CI, 22% to 52%) of patients receiving 6 months of low- and high-dose octreotide, respectively. Ten percent and 13% of patients in each treatment group developed transient diarrhea; 10% and 14%, biliary sludge; and 6% and 18%, cholelithiasis, respectively. CONCLUSION: Octreotide effectively decreased GH and IGF-1 concentrations in 53% and 68% of patients, respectively. The higher dose resulted in increased frequency of tumor shrinkage but added no biochemical or clinical benefit.

Acromegaly↗
PubMed1992

Pituitary lactotrophs and somatotrophs in pregnancy: a correlative in situ hybridization and immunocytochemical study.

Lactotroph hyperplasia is a prominent finding in the adenohypophyses of pregnant women. In order to elucidate the morphogenesis of this change, pituitaries from 16 women in various phases of pregnancy were collected at autopsy and studied by histology, immunocytochemistry and in situ hybridization. The results showed that the increase in the amount of prolactin (PRL) mRNA paralleled the progressive lactotroph hyperplasia. The presence of mitoses in PRL-immunoreactive cells provided evidence that proliferation of preexisting lactotrophs contribute to lactotroph accumulation. Growth hormone (GH) immunoreactive cells showed a marked reduction in GH mRNA indicating that GH synthesis was inhibited. In many GH-immunoreactive cells, PRL mRNA became apparent. These findings demonstrate that GH is stored following discontinuation of GH synthesis. It appears that, when PRL is secreted in excess during pregnancy, somatotrophs are recruited to produce PRL. These somatotrophs begin to express PRL mRNA, transform to bihormonal mammosomatotrophs and possibly later to lactotrophs, contributing to PRL production. Mature somatotrophs may be regarded as reserve cells in the adenohypophysis, having the potential to switch hormone synthesis and to convert to mammosomatotrophs and possibly lactotrophs.

Adolescent↗
PubMed1992

The pituitary gland in hyperthyroidism.

The pituitary glands of 33 patients (24 women and 9 men, 18 to 78 years old) who died in thyrotoxicosis (18 with Graves' disease and 15 with toxic multinodular goiter [Plummer's disease]) were examined by histologic and immunocytologic methods. Thirteen patients (39%) died in "thyroid storm." The avidin-biotin-peroxidase complex immunostaining method was used to demonstrate the spectrum of pituitary hormones, including growth hormone, prolactin, adrenocorticotropic hormone, thyrotropin, follicle-stimulating hormone, luteinizing hormone, and alpha-subunit. The most striking finding was a pronounced decrease or loss of immunoreactivity to thyrotropin in all thyrotoxic cases, a consistent change that allowed ready distinction of thyrotoxic from euthyroid pituitary glands. When immunoreactive thyrotrophs were identified, they were sparse and small and demonstrated only faint thyrotropin reactivity. No morphologic differences were noted between the pituitary glands of patients with Graves' disease or Plummer's disease or between sexes. Loss of thyrotropin immunoreactivity was found to be reversible in that thyrotropic cells in the pituitary glands of 16 additional concurrently studied patients, who had thyrotoxicosis but were treated and subsequently had normal thyroid function or hypothyroidism, appeared normal or even hyperplastic. Other types of adenohypophysial cells in both the thyrotoxic and the successfully treated groups exhibited no abnormalities. Pituitary adenomas were incidental findings in 6 of the 33 patients (18%). Their immunotypic spectrum included three prolactin-immunoreactive tumors, two growth hormone-containing adenomas (one of which was plurihormonal), and one tumor with follicle-stimulating hormone and luteinizing hormone; no thyrotropin-containing adenomas were noted. No examples of pituitary hyperplasia were encountered in pituitary glands of thyrotoxic patients, and no hypophysitis or fibrosis was noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1992

The pituitary gland in patients with breast carcinoma: a histologic and immunocytochemical study of 125 cases.

Pituitary glands obtained at autopsy of 125 women with disseminated breast carcinoma were studied to determine whether pituitary prolactin cell abnormalities (hyperplasia or adenoma) might be involved in the pathogenesis of breast carcinoma. In addition, we studied 85 pituitary glands obtained from unselected, consecutive autopsies in women without breast carcinoma but who died of other diseases (control group). The frequency of lactotroph hyperplasia was slightly higher in patients with breast carcinoma than in the control group, but the difference was not statistically significant, nor were differences in the frequency and size of pituitary adenomas, prolactin-producing or otherwise. No correlation was found between the presence of lactotroph hyperplasia or prolactin-producing adenomas (or both) and such factors as the patient's age, bilaterality of the carcinoma, previous treatment with tamoxifen citrate or oophorectomy, stage of disease, or survival. The frequency of breast carcinoma metastatic to the pituitary gland was higher in the study group than in the control group; however, the difference was not statistically significant. No preferential site of metastatic involvement in the pituitary gland was noted. Relative proportions of other lesions such as infarcts, cysts, lymphocytic infiltrates, and basophilic invasion were similar in the study and control groups. This study indicates that accumulation of prolactin cells, whether hyperplastic or adenomatous, cannot be considered a major risk factor for the genesis or progression of breast carcinoma.

Adenoma↗
PubMed1992

Cushing's syndrome associated with ectopic production of corticotrophin-releasing hormone, corticotrophin and vasopressin by a phaeochromocytoma.

We describe a case of Cushing's syndrome caused by a phaeochromocytoma secreting corticotrophin-releasing hormone (CRH) and corticotrophin (ACTH). A 49-year-old white woman presented with a 1-month history of lower limb oedema, polydipsia and polyuria. Physical examination revealed a patient with plethoric facies, lanugo-type facial hair, central obesity, red abdominal striae, lower limb oedema, and blood pressure of 210/115 mmHg. Laboratory studies showed high plasma ACTH and markedly elevated urinary cortisol excretion that suppressed more than 50% with high-dose dexamethasone administration. Computed tomographic scan of the abdomen showed a 4-cm left adrenal tumour. Catecholamines and metabolites were markedly increased in a 24-hour urine collection. Results of venous catheterization studies showed that CRH and ACTH were secreted by the tumour. In addition, with ovine CRH administration, inferior petrosal sinus sampling showed pituitary secretion of ACTH. Left adrenalectomy resulted in complete remission of Cushing's syndrome. Light microscopic and immunohistochemical studies revealed a phaeochromocytoma that produced CRH, ACTH and vasopressin. RNA studies showed that this tumour, in contrast to normal adrenal and other reported phaeochromocytomas, transcribed a lone pituitary-sized (1200 nucleotide) pro-opiomelanocortin mRNA. This is the second reported case of a CRH-secreting phaeochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1992

C-peptide suppression test: effects of gender, age, and body mass index; implications for the diagnosis of insulinoma.

To assess the effects of gender, age, and body mass index (BMI) on suppression of plasma C-peptide during insulin-induced hypoglycemia, 101 lean and obese, healthy men and women ages 20 to 80 yr underwent infusion of human regular insulin, 0.125 U/kg over 60 min after an overnight fast. Plasma glucose, insulin, and C-peptide were measured every 30 min for 120 min. C-peptide concentrations were influenced by gender at 30 min, by BMI at baseline and both BMI and age at all subsequent time points. Because of variations in baseline plasma C-peptide concentrations, percent decrease in C-peptide was evaluated. Significantly less percent decrease of C-peptide with increased age at 30, 60, and 90 min and with increased BMI at 30 and 60 min were noted with no effect of gender. From stepwise regression analysis using multiple, additional variables only the plasma glucose concentration at 30 min made a significant, albeit small (8%), contribution to the variability in percent decrease in C-peptide at 60 min. When C-peptide responses from eight histologically confirmed insulinoma patients were contrasted to values adjusted for age, gender, and BMI of normal subjects, all insulinoma patients had abnormal responses when percent decrease in C-peptide was used, whereas only four insulinoma patients had abnormal response when actual C-peptide concentrations were used.

Adult↗
PubMed1992

Coexisting corticotroph and lactotroph adenomas: case report with reference to the relationship of corticotropin and prolactin excess.

A 57-year-old obese woman with hypertension, diabetes mellitus, osteoporosis, and a 40-year history of secondary amenorrhea was diagnosed with corticotropin-dependent Cushing's syndrome. Dynamic endocrine testing and radiological evaluation did not reveal definitively the source of the excess corticotropin. Bilateral adrenalectomy was performed with resolution of the signs and symptoms of hypercortisolism. Four years later, the patient was noted to have rising serum corticotropin levels and an enlarging pituitary mass; hyperprolactinemia also was documented. A diagnosis of Nelson-Salassa syndrome was made, and she underwent a transsphenoidal adenomectomy. A histological examination of the specimen revealed two distinct, albeit contiguous, adenomas: a corticotroph adenoma and a lactotroph adenoma. Postoperatively, the serum prolactin and corticotropin levels decreased significantly. Although the stalk section effect resulting from compression by a pituitary adenoma can raise serum prolactin levels, a concurrent lactotroph adenoma should be considered in patients with nonfunctional or functional pituitary adenomas of other types associated with significantly elevated prolactin levels. The mechanisms underlying simultaneous adrenocorticotropic hormone and prolactin excess are discussed.

Adrenal Cortex↗
PubMed1990

Association of hypokalemia, aldosteronism, and renal cysts.

The recognition of renal cysts in two patients with chronic hypokalemia and the renal effects of hypokalemia in certain species of animals prompted this study of the possible association of hypokalemia and renal cysts in patients with primary aldosteronism or primary renal potassium wasting. Using CT scans, we studied 55 patients with primary aldosteronism, of whom 24 had cysts (44 percent). The cysts were more frequent in patients with adrenal tumors than in those with idiopathic adrenal hyperplasia. Sixteen of the 26 patients with tumors (62 percent) had renal cysts, which were often multiple and located in the medulla. Lower plasma potassium levels and higher serum aldosterone levels, urinary aldosterone excretion, and plasma renin activity were correlated with the extent of the cystic disease. Sequential observations indicated that prolonged hypokalemia can be accompanied by the development of renal scarring and that the size and number of cysts can decrease markedly in some patients after the removal of an adrenal adenoma. The association of hypokalemia, aldosteronism, and renal cysts was also supported by the finding of multiple medullary cysts in two patients with primary renal potassium wasting. We conclude that chronic hypokalemia is accompanied by enhanced renal cytogenesis and may lead to interstitial scarring and renal insufficiency. Renal cysts are thus dynamic structures whose growth can be influenced by hormonal or pharmacologic interventions.

Adenoma↗