Adrenal and paraganglia

Question 1

Adrenal tumour with a variable number of ganglion cells set within Schwannian stroma. Must not have visible neuropil. Ganglion cells are large, with eccentric round nucleus, prominent nucleolus, and granular eosinophilic cytoplasm, which may contain lipofuscin/neuromelanin or Nissel substance. Schwann cells are bland spindle cells with wavy nuclei set within a fibrillary collagenous stroma.

Answer 1

Ganglioneuroma

Differential diagnosis: Ganglioneuroblastoma

Plan:
Correlate with clinical history and radiologic features
Examine further blocks [extensively sample lesion] (to exclude a component of neuroblastoma which would indicate ganglioneuroblastoma)
IPX to support Dx: S100, synaptophysin (expect positive)

Question 2

Head/neck region tumour with Zellballen architecture composed of nests of chief cells with abundant pale eosinophilic cytoplasm and neuroendocrine nuclei surrounded by highly vascular stroma. Mitotic figures are usually rare.

Answer 2

Parasympathetic paraganglioma

Differential diagnosis:
Neuroendocrine tumour
Parathyroid adenoma
Medullary thyroid carcinoma

Plan:
Correlate with clinical history and radiographic features (?familial syndrome)
IPX to support Dx: AE1/AE3, synaptophysin and chromogranin, GATA3, S100 (expect cytokeratin negative, others positive, S100 stains sustentacular cells)
IPX to discount DDx: PTH, calcitonin
IPX to evaluate familial syndromes: SDHB, CAIX
Next steps: Synoptic report, discuss at MDT
Advice to clinician: May be associated with familial syndrome (SDH deficiency, VHL) Clinical correlation is required.

Question 3

Adrenal tumour with “Zellballen” architecture with nests of tumour cells separated by capillaries. Cells have granular amphophilic cytoplasm. Nuclei are neuroendocrine (round and finely speckled) but can also show neuron-like vesicular chromatin with a conspicuous nucleolus, or degenerative/endocrine atypia. Mitotic figures are usually rare.

Answer 3

Phaeochromocytoma

Differential diagnosis:
Adrenal cortical adenoma or carcinoma

Plan:
Correlate with clinical history and radiographic features (?catecholamine secretion ?familial syndrome ?size/necrosis radiologically)
Examine further blocks (e.g. for margins, atypical features)
IPX to support Dx: AE1/AE3, synaptophysin and chromogranin, GATA3, S100 (expect cytokeratin negative, others positive, S100 stains sustentacular cells)
IPX to discount DDx: Melan-A, SF1
IPX to evaluate familial syndromes: SDHB, CAIX, FH and 2SC, MAX
Next steps: Risk straficiation (e.g GAPP, PASS scores), synoptic report, discuss at MDT
Advice to clinician: May be assiociated with familial syndromes. Clinical correlation is required.

Question 4

Well circumscribed adrenal tumour composed of mature adipocytes and haematopoietic cells of all three lineages

Answer 4

Myelolipoma

Plan:
Correlate with clinical history and radiology (?congenital adrenal hyperplasia)
Otherwise, no specific action required for this benign diagnosis