Lung Flashcards
cystic lung lesions
bronchogenic cyst
ciliated foregut cyst
enterogenous cyst
CCAM
sequestration
bronchial atresia
congenital lobar overinflation
mesothelial cyst
lymphatic malformation
pleuropulmonary blastoma
CPAM vs sequestration
CPAM: communicates with tracheobronchial tree, normal pulmonary artery supply, 3 types (depend on number and size of cyst)
Seq: prominent systemic artery, extralobar (own pleural covering) or intralobar
spindle cell lesions
non-neo: mycobacterial pseudotumour, organizing pneumonia
epithelial: spindle cell carcinoid, spindle cell carcinoa, thymoma
mesenchymal: SFT, IMT, synovial sarcoma, lymphangioleiomyomatosis, PEComa, leiomyoma/LMS, Kaposi sarcoma
mesothelioma
melanoma
biphasic lesions
carcinoid
adenosquamous ca
carcinosarcoma
synovial sarcoma
fetal adenocarcinoma (looks like endometrioid ca with sq morules)
pulmonary blastoma (adults, fetal adenoca-like with malignant primitive stroma)
pleuropulmonary blastoma (kids, benign cystic glands with malignant primitive stroma)
pleomorphic sarcoma
benign mimics of malignancy
squamous metaplasia (vs SCC)
florid type II pneumocyte hyperplasia (vs malignancy)
hamartoma (vs bland ca/sarc)
meningothelial-like nodules (vs carcinoid)
sclerosing pneumocytoma/’haemangioma’

Sclerosing pneumocytoma:
papillary, solid, sclerosed or angiomatous
cuboidal surface cells, round stromal cells
EMA, TTF1+
surface cells CK+
malignant mimics of benign
subtle metastases (eg lobular ca)
malignancy obscured by inflammation
almost normal
SECRET ALV
sequestration
emboli: fat, amniotic fluid, marrow, brain, liver, foreign body
CMV
RB
emphysema
pulmonary hypertension
amyloid
lymphangioleiomyomatosis (SMA, HMB45+)
vasculitis
neuroendocrine tumours
typical carcinoid: <2 mit/2mm2, no necrosis (tumorlet if = 5mm)
atypical carcinoid: 2-10 mit/2mm2, punctate necrosis
large cell neuroendocrine ca: >10 mit/2mm2, large necrosis, organoid with palisades and/or rosettes, lower NC ratio
small cell ca: >10 mit/2mm2, large necrosis, molding, crush artefact, size less than 3 lymphocytes
AAH vs AIS vs MIA/adenoca
AAH (usu has ca too): <5mm, mildly atypical pneumocytes, ‘peg like’
AIS: lepidic growth, no invasion, septal sclerosis common
MIA: = 3cm, <5mm invasion (and no LVI, necrosis or STAS)
NB: these are all RESECTION ONLY. If biopsy, call ‘lepidic growth’ only.
NB: if >3cm, call lepidic predominant adenoca

Pulmonary blastoma (basal nuclei, clear cytoplasm)

Pleomorphic (spindle and giant cell) carcinoma

Basaloid carcinoma

Bronchial mucous gland adenoma
primary lung vs thymic ca
thymic: CD5, CD117+
eosinophilic reactions
simple eosinophilia (no reaction)
acute eosinophilic pneumonia (DAD)
chronic eosinophilic pneumonia (organising DAD and organising pneumonia)
allergic bronchopulmonary aspergillosis (allergic mucin +/- aspergillus in large bronchi)
bronchocentric granulomatosis (granulomas only in bronchioles, related to CEP/ABPA)
DDX for bronchocentric granulomas
bronchocentric granulomatosis
TB
fungal
Wegener granulomatosis
rheumatoid nodule
cystic fibrosis
eosinophils
idiopathic
drugs
infection: aspergillus, parasites
inflammation: asthma, Churg-Strauss
neoplasms: LCH, mastocytoma, lymphomas
granulomas
infection
drugs
foreign body
sarcoid
hypersensitivity pneumonia
vasculitis (Wegener, Churg-Strauss)
collagen vascular disease (SLE, RA)
bronchocentric granulomatosis
malignancy
granulomatous infections
TB
MAIC (hot tub lung, small bronchioles)
fungal
parasites
granulomatous foreign body
always polarise!
aspiration pneumonia
IV drug users
talc, silicon, aluminium, beryllium
histiocytes
MAIC
Whipples
malakoplakia
DIP/RB
lipoid pneumonia
Rosai-Dorfman
LCH
lymphoma
Aspergillus infections
aspergilloma: colonisation of existing cavity
ABPA: ILD, may not see fungi
acute invasive aspergillosis: invades vessels
infections
CMV
measles
TB/MAIC
Aspergillus
Histoplasma (necrotising granuloma)
Cryptococcus (granuloma, mucicarmine+)
Pneumocystis (frothy pink material in alveoli, GMS+ cf diffuse alv proteinosis: PAS+)
Toxoplasma (GMS, giemsa+)
lymphoid infiltrate
LIP: dense mononuclear, along septa
nodular lymphoid hyperplasia
follicular bronchitis/bronchiolitis
BALT lymphoma: confluent monotonous cells
lymphomatoid granulomatosis: necrosis, angioinvasive, large atypical CD20/EBV+ cells
other lymphomas (esp DLBCL)
ILD - histologic patterns
(report these, clinical terms in bracket)
DAD (AIP)
organising pneumonia (COP)
UIP (idiopathic pulmonary fibrosis) - look for asbestos bodies
NSIP
DIP
LIP
RB (RB-ILD)
Before calling idiopathic, exclude…
infection
sepsis
shock
inhalants
drugs
radiation
autoimmune disorders
haemorrhage
antibody mediated: Goodpasture (anti BM IgG, linear IgG on DIFL)
immune complex mediated: SLE (‘full house’ on DIFL)
pauci immune: Wegener (c-ANCA), MPA (p-ANCA)
idiopathic pulmonary haemosiderosis
clear cell lesions
clear cell/sugar tumour
clear cell SCC
mets: RCC, ACC, seminoma