Your Visual Guide Pituitary Tumors

Understand this diagnosis through data, infographics, and evidence based on modern classification and current research.

~15,000
New Pituitary Tumor Cases per Year (U.S.)
Understanding Pituitary Tumors
What Are Pituitary Tumors & How Are They Classified?
Pituitary tumors (pituitary neuroendocrine tumors, PitNETs) are classified by hormone production and cell lineage. Functioning tumors secrete excess hormones; non-functioning present with mass effect.
Pituitary Neuroendocrine Tumor
Hormone Status?
Functioning (~65%)
Functioning (~65%) (~65%)
Hormone-secreting tumors
Prolactinoma GH-secreting ACTH-secreting TSH-secreting
Non-Functioning (~35%)
Non-Functioning (~35%) (~35%)
Mass effect, visual field loss
Gonadotroph Null cell Silent corticotroph
Aggressive/Atypical
Aggressive/Atypical (<5%)
Ki-67 >3%, invasion, recurrence
Atypical adenoma Pituitary carcinoma
Tumor Grading
Pituitary Tumor Classification
Pituitary tumors are classified by hormone secretion (functioning vs non-functioning) and cell lineage.
1
Prolactinoma
Most common functioning pituitary tumor (~40%). Secretes prolactin. Usually responds to dopamine agonist medical therapy without surgery.
2
GH-secreting (Acromegaly)
Causes acromegaly in adults, gigantism in children. Somatotroph lineage (PIT1+). Treated with surgery and somatostatin analogs.
3
ACTH-secreting (Cushing Disease)
Causes hypercortisolism. Often microadenomas (<10mm). Corticotroph lineage (TPIT+). Transsphenoidal surgery is first-line.
4
TSH-secreting
Rarest functioning adenoma (<1%). Causes central hyperthyroidism. Thyrotroph lineage. Surgery and somatostatin analogs.
5
Nonfunctioning Pituitary Adenoma
Clinically silent, no hormone excess. ~30% of pituitary tumors. Presents with mass effect (visual field defects, headache).
6
Craniopharyngioma
Not a true pituitary adenoma. Adamantinomatous (CTNNB1 mutation) or papillary (BRAF V600E). Arises from Rathke pouch remnants.
7
Aggressive/Carcinoma
Rare aggressive PitNETs with rapid growth, invasion, or resistance to standard therapy. Temozolomide is key treatment.
Molecular Markers
The Key Biomarkers
Modern classification depends on specific molecular markers. Each reveals something different about the tumor.
Diagnostic
USP8
Ubiquitin-Specific Protease 8
Hotspot mutations in ~40% of corticotroph adenomas (Cushing disease). Activates EGFR signaling.
Cushing disease
Diagnostic
GNAS
G-Protein Alpha Subunit
Activating mutations (McCune-Albright) in ~40% of GH-secreting adenomas. Constitutive cAMP signaling.
Acromegaly
Predictive
MEN1
Menin
Germline mutations cause MEN1 syndrome: pituitary, parathyroid, and pancreatic tumors. Screen family members.
MEN1 syndrome
Predictive
AIP
Aryl Hydrocarbon Receptor IP
Germline mutations cause familial isolated pituitary adenoma (FIPA). Young-onset, often GH-secreting.
FIPA syndrome
Predictive
BRAF V600E
BRAF Kinase Mutation
Defines papillary craniopharyngioma. Potential target for BRAF/MEK inhibitor therapy (vemurafenib+cobimetinib).
Papillary cranio
Diagnostic
CTNNB1
Beta-Catenin
Mutations define adamantinomatous craniopharyngioma. Nuclear accumulation on IHC. Distinct from papillary subtype.
Adamantinomatous
Diagnostic
PIT1
Pituitary Transcription Factor
Expressed in GH, PRL, and TSH lineage tumors. Key for pituitary adenoma lineage classification.
Lineage marker
Diagnostic
TPIT
T-Box Transcription Factor
Expressed in corticotroph lineage. Defines ACTH-secreting adenomas and silent corticotroph tumors.
Corticotroph
Signs & Symptoms
Pituitary Tumor Signs & Symptoms
Symptoms arise from hormone excess, hormone deficiency, or mass effect on surrounding structures.

Visual Field Defects

Bitemporal hemianopia from optic chiasm compression. Most common presenting symptom of large nonfunctioning adenomas.

Headache

Sellar/parasellar pressure. Can be severe with apoplexy (hemorrhage into tumor).

Hormonal Excess

Acromegaly features (GH), Cushingoid features (ACTH), galactorrhea/amenorrhea (prolactin), hyperthyroidism (TSH).

Hypopituitarism

Deficiency of one or more anterior pituitary hormones from compression of normal gland.

Diabetes Insipidus

Rare with adenomas; more common with craniopharyngioma or postoperatively. Excessive thirst and urination.

Pituitary Apoplexy

Acute hemorrhage or infarction: sudden headache, visual loss, ophthalmoplegia. Neurosurgical emergency.

Diagnosis
The Diagnostic Journey
From hormonal evaluation to imaging — the path to a pituitary tumor diagnosis.
1

Hormonal Testing

Complete anterior pituitary panel: prolactin, IGF-1, cortisol, thyroid function, gonadotropins

2

MRI Sella

Dedicated pituitary protocol MRI with gadolinium and dynamic contrast sequences

3

Visual Field Testing

Formal perimetry to assess optic chiasm compression and monitor treatment response

4

Dynamic Endocrine Tests

Dexamethasone suppression, glucose tolerance, CRH stimulation for specific diagnoses

5

IPSS

Inferior petrosal sinus sampling for ACTH-dependent Cushing syndrome lateralization

6

Treatment Plan

Based on tumor type, size, hormone status, visual function, and patient goals

Treatment
Treatment Options for Pituitary Tumors
Treatment varies by tumor type: medical therapy for prolactinoma, surgery for most others, radiation for refractory cases.

Transsphenoidal Surgery

Endoscopic endonasal approach is standard. High cure rates for microadenomas. Preserves pituitary function in experienced hands.

Dopamine Agonists

First-line for prolactinoma: cabergoline or bromocriptine. Normalizes prolactin and shrinks tumor in >90% of cases.

Somatostatin Analogs

Octreotide LAR, lanreotide for acromegaly. Normalize IGF-1 in ~50-70%. Tumor shrinkage in ~20-30%.

Radiation Therapy

SRS (Gamma Knife) or fractionated for residual/recurrent tumors. Hormonal normalization over years.

Temozolomide

For aggressive pituitary tumors and carcinomas. MGMT methylation predicts response. 6-month trial standard.

Clinical Trials

Immunotherapy, targeted agents (BRAF/MEK for craniopharyngioma), and novel medical therapies under investigation.

Find matching trials →
Care Team
Your Multidisciplinary Care Team
Pituitary tumor management requires close collaboration between endocrinology and neurosurgery at a specialized center.
Core Specialists

Neurosurgeon

Primary specialist for surgical resection and skull base approaches

Radiation Oncologist

Plans and delivers radiation therapy and stereotactic radiosurgery

Neuro-oncologist

For higher-grade or refractory pituitary tumors requiring systemic therapy

Support Team

Neuroradiologist

Specialized imaging interpretation and monitoring

Neuropathologist

Tissue analysis, WHO grading, and molecular profiling

Nurse Navigator

Guides you through appointments, insurance, and logistics

Resources
Support Organizations
Organizations providing information, community, and support for pituitary tumor patients.

Pituitary Network Association

Dedicated to pituitary tumor patient support, education, and advocacy for improved treatment.

Visit Pituitary Network Association →

Cushing's Support & Research Foundation

Specifically supporting Cushing disease and syndrome patients with resources and research.

Visit Cushing's Support & Research Foundation →

Acromegaly Community

Support and resources for acromegaly patients and families navigating treatment and follow-up.

Visit Acromegaly Community →

National Brain Tumor Society

Leading nonprofit investing in research, advocacy, and patient services for all brain tumors.

Visit National Brain Tumor Society →

Want to Explore Clinical Trials?

Search clinical trials for pituitary tumors and find the ones that match your specific diagnosis and hormone profile.

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