Introduction
Measurement of GH and IGF-1 in acromegaly
Biochemical versus symptom control
Tumor shrinkage
Control of comorbidities
A 40 year-old female was referred to the endocrinologist in April 2008 due to amenorrhea over the previous 10 months
|
Symptoms |
Increased shoe size (from 35 to 38) |
Oily skin, excessive sweating |
Excessive snoring |
Amenorrhea (10 months) |
Polyarthralgia |
Signs |
Height: 1.56 m |
Weight: 66.3 kg |
Blood Pressure (BP): 160/100 mmHg |
Enlarged hands and feet |
Macroglossia, diastema |
Prognathism, dental malocclusion |
No goiter |
Personal and family history |
No family history of diabetes, cancer, thyroid disease or pituitary disease |
The last medical evaluation was made in 2004; no biochemical abnormality was found |
Lab tests |
GH (ICMA): 23.8 μg/L |
IGF-1 (ICMA): 960 μg/L (normal 101–267 μg/L) |
GH nadir during OGTT: 6.3 μg/L |
Prolactin and thyroid function tests: normal |
Estradiol: 46 pmol/L (12.6 pg/mL) |
FSH: 0.8 IU/L |
Fasting plasma glucose: 7.6 mmol/L (137 mg/dL) |
HbA1c = 7.4 % |
Serum calcium: normal |
Triglycerides: 5.5 mmol/L (487 mg/dL) |
HDL cholesterol: 0.8 mmol/L (31 mg/dL) |
Diagnosis |
Acromegaly caused by a GH-secreting pituitary macroadenoma |
MRI |
Macroadenoma (2.3 × 1.8 cm), with infrasellar, parasellar and suprasellar extension (Fig. 1) |
Computerized visual field testing ⇒ Normal |
Echocardiogram |
Marked left ventricular (LV) hypertrophy |
No valvular abnormalities |
Treatment |
Patient was submitted to transsphenoidal surgery in Sept 2008, which was not curative (Fig. 1) |
IGF-1: 802 μg/L (normal 101–267 μg/L) |
GH: 13.6 μg/L |
GH nadir: 3.7 μg/L |
SSA was started in March 2009, followed by a higher dose in May 2009 followed by SSA + cabergoline 3 mg/week |
IGF-1 response to medical treatment showed improvement to normal range (101–267 μg/L) with sequential medical therapy from 780 μg/L to 253 μg/L |
Thyroid ultrasound |
June 2008: normal |
January 2011: 1.7 cm hypoechoic solid nodule with increased blood flow in right lobe |
FNA biopsy ⇒ Papillary thyroid carcinoma |
March 2011 ⇒ Total thyroidectomy |
Thyroid histology ⇒ BRAF
V600E-positive tall cell variant papillary thyroid carcinoma |
Patient’s comorbidities |
Thyroid carcinoma |
Diabetes mellitus |
Dyslipidemia |
Left ventricular hypertrophy |
Polyarthralgias |
Central hypogonadism |
Excessive snoring (sleep apnea?) |
Effect of treatment on comorbidities |
Thyroid carcinoma ⇒ No evidence of disease recurrence or metastasis after total thyroidectomy and 131I abalation therapy |
Diabetes ⇒ Metformin XR (750 mg/d) required to control blood glucose and HbA1c levels |
Dyslipidemia ⇒ resolved with the improvement of diabetes and normalization of GH and IGF-1 levels |
Hypertension ⇒ BP control achieved with losartan + amlodipine + indapamide |
Central hypogonadism/excessive snoring ⇒ resolved with GH/IGF-1 normalization |
LV hypertrophy ⇒ improvement after BP control and hormonal normalization |