A non-functioning pituitary adenoma is a pituitary adenoma that is not hormonally active (in other words, not associated with clinical syndromes such as amenorrhea-galactorrhea in the context of prolactinomas, acromegaly, Cushing’s disease, or hyperthyroidism secondary to TSHomas). They account for 15-30% of pituitary adenomas. 98
Table 20 presents data on the prevalence of non-functioning adenomas. No incidence data were available.
|POPULATION||METHOD||DATA SOURCE||PREVALENCE PER 100,000||REFERENCE|
|UK (n=81,149)||Review of clinical data||16 surgical centers in Banbury||22.2||Fernandez et al. 201074|
|Sweden (n=592 adult patients diagnosed with PAs)||Review of clinical data||Swedish Pituitary Registry||1.8
|Tjonstrand et al. 201499|
|Review of clinical data||Nationwide health registries in Sweden||2.0
|Olsson et al. 2015100|
|Iceland (n=471)||Review of clinical data||All pituitary adenomas diagnosed in Iceland 1955-2012||42.32||Agustsson et al. 201573|
Abbreviations: UK, United Kingdom; n, number.
A retrospective cohort study that examined insurance claims databases reported that in 2008, the annual cost of treating clinically non-functioning adenomas was $13,708 per patient in the US 101
A very large Swedish registry study of patients with non-functioning pituitary adenomas showed an overall excess mortality in women and in patients with a young age at diagnosis. Increased mortality was seen for cerebrovascular and infectious diseases.100
A study in the United Kingdom reported that only age at diagnosis remained an independent predictor of mortality (hazard ratio 1.10; 95% CI, 1.07-1.13, p<0.001), whereas sex, presentation with acute apoplexy, extent of tumor removal, radiotherapy, recurrence, untreated GH deficiency, follicle-stimulating hormone/luteinizing hormone deficiency, ACTH deficiency, TSH deficiency, and treatment with desmopressin for CDI had no impact.102 Tables 21 summarizes data on life expectancy and mortality of patients with non-functioning adenomas.
|UK (n=546)||Retrospective cohort study in a tertiary referral center in the UK||SMR was 3.6 (95% CI, 2.9-4.5), for those operated before 1990, 4.7 (95% CI, 2.7-7.6) and for those after 1990, 3.5 (95% CI, 2.8-4.4).||N/A||N/A||Ntali et al. 2015102|
|Denmark (n=160)||Patient follow-up (mortality calculated 12.4 years after operation)||1.18 (95% confidence limits (CI) 0.87-1.60).||0.83 (CI 0.55-1.26).||1.97 (CI 1.20-3.21)
|Lindholm et al. 2006103|
|Sweden (n=2,795 patients with non-functioning pituitary tumors)||Review of clinical data||SMR of 1.10 (1.00-1.20).||1.29 (CI 1.11-1.48)||1.29; (CI 1.11-1.48)||Olsson et al., 2015100
Abbreviations: SMR, standardized mortality ratio; UK, United Kingdom; n, number; N/A data not available.
Table 22 presents data on key trends and health outcomes related to the treatment of non-functioning adenomas.
|Italy (n=84)||Surgery||In the non-surgical group (33 patients), the macroadenomas showed a 15% probability of tumor growth and reduction. Similar tumor size alterations were observed also for the microadenomas. In the surgical group (51 patients), both classes of tumor remnants (>1 and <1 cm) remain mainly stable postoperatively through the time of last imaging.||Karamouziz et al. 2015104|
|Italy(n=68)||Fractionated radiotherapy for non-functioning pituitary tumors||49 patients had a tumor reduction, 16 remained stable, and three progressed.||Minniti et al. 2015105
Abbreviation: n, number.