TUMOR · TOPIC
MECHANISM · GENETICS
FEATURES
CLUE · TREATMENT
Chromaffin cell tumor of the adrenal medulla; secretes epinephrine and norepinephrine episodically
Paroxysms: headache, sweating, palpitations/tachycardia, pallor, anxiety; sustained or episodic HTN; hyperglycemia
Triggers: anesthesia, tumor palpation, tyramine, metoclopramide, β-blockers
Tumor metabolizes catecholamines continuously
↑ plasma free metanephrines or 24-h urine metanephrines, VMA; then CT/MRI, MIBG
Metanephrines more sensitive than catecholamines
Neuroendocrine nests
Nests ("Zellballen") of polygonal cells with salt-and-pepper chromatin; chromogranin ⁺; S100 ⁺ sustentacular cells
Malignancy defined only by metastasis
Up to ~1/3 germline: RET (MEN2A/2B), VHL, NF1, SDHB/SDHD, MAX, TMEM127
Young age, bilateral, extra-adrenal, family history
Old "rule of 10s" understates heredity
Block α-receptors first, then β
Phenoxybenzamine (irreversible α) or doxazosin 1–2 weeks → β-blocker for tachycardia → adrenalectomy; volume expansion
β-blocker first → unopposed α → hypertensive crisis
Extra-adrenal chromaffin tumor (sympathetic) or head-neck (parasympathetic); SDH mutations
Organ of Zuckerkandl (aortic bifurcation), bladder (headache/syncope with urination), carotid body (painless neck mass)
Extra-adrenal tumors make norepinephrine only (no PNMT)
Neuroblastoma
most common extracranial solid tumor of infancy
Neural crest; adrenal medulla or anywhere along the sympathetic chain
Child < 2: firm, irregular abdominal mass that crosses the midline; calcifications; HTN less common
↑ urine HVA and VMA
Neuroblastoma — pathology & genetics
Small round blue cells, Homer-Wright rosettes; synaptophysin, NSE ⁺
MYCN (N-myc) amplification → poor prognosis; age < 18 months → better
Stage MS (4S) infants may regress spontaneously
Neuroblastoma — spread & paraneoplastic
Metastasizes to bone, orbit, liver, skin
Periorbital bruising ("raccoon eyes"), "blueberry muffin" skin nodules, bone pain; opsoclonus-myoclonus ("dancing eyes, dancing feet")
Opsoclonus: anti-neuronal antibodies
Benign, fully mature neural crest tumor
Older children/adults; posterior mediastinum or adrenal
Ganglion cells + Schwann stroma
Adrenal metastases & incidentalomas
Adrenals are common metastatic sites (lung, breast, melanoma)
Incidental adrenal mass → test for cortisol, aldosterone (if HTN), metanephrines
Bilateral mets can cause Addison