JC WCS 16: PLEURAL EFFUSION & BRONCHIAL CARCINOMA

JC WCS 16: PLEURAL EFFUSION & BRONCHIAL CARCINOMA
Prof WK Lam

Medicine

Mon 11-11-02
PLEURAL EFFUSION

INTRODUCTION

Abn accum fluid in pleural space

Normal form'n pleural fluid

Usu. few mm fluid in pleural space ® lubricate visc + parietal layers

Pro of pleural fluid = 15g/L

Maintained by balance (disruption = abn pleural fluid)

Hydrostatic press caps: force fluid fr BV ® pleural space (9cm H2O)

Oncotic press: draw fluid into BV (10cm H2O)

Pleural cap perm'y

Pleural lymphatic drainage

BV (1) Parietal pleura = systemic a's (2) Visceral pleura = low press pul circ

Fluid filtered fr arterial cap on parietal side ® most resorb by venous cap on visceral side (remainder + filtered pro ® lymphatics)

AETIOLOGY

Transudate = ¯ pro pleural fluid ( hydrostatic, ¯ oncotic press)

Exudate = pro pleural fluid ( cap perm, ¯ lymphatic drainage)

Hydrostatic press

CHF
Renal F (H2O reten'n)
Other vol o'load

¯ Oncotic press (¯ albumin: ¯ product'n vs. loss - usu kid, rarely GIT)

Cirrhosis: ¯ product'n

Nephrotic syndr: loss

Severe malnutrit'n: ¯ product'n

Other h-albuminaemia

Cap perm'y (inflamed pleura)

Infect'n lung/pleura (incl. TB)
Collagen vasc dis (vasculitis)
Malig
Intraab (pancreatitis, liver abscess)
Pul embol'm

¯ Lymphatic drainage

Malig infiltration lymphatics (mediast, pul, pleural)
Necrotising/ granulomatous infect'n (HK = TB, Other = fungal)
Pleural fibrosis

CLINICAL FEATURES (dep. effusion size)

Asympt to SOB
Irritant cough
Chest pain (pleural acutely inflam - "pleuritic")
Other rel to u'lying dis

P/E

< 500ml - no sign

Mod - dull percuss'n, ¯ breath sound/ fremitus

>1500ml - as above + insp lag (¯ expansion), medias shift

Atelectasis (lung collapse) above effusion (bronchial BS, aegophony - high-pitch nasal speech b/c low-freq sounds dispersed)

Other: ankle oedema (CHF), lymphadenopathy (malig)

INVESTIGATIONS

CXR

PA - ³ 300ml, blunt costophrenic ang, fluid meniscus shadow

Lat - fluid meniscus (free-flow) vs. pockets (loculated)

Lat decubitus - sm effus'n, confirm free-flow

Contralat mediast shift if ³ 1500ml (no shift if collapse)

Other: pul congest'n, lung mass, rib erosion

US pleura

Non-Dx CXR
Sm effus'n 10-15mm on lat decub CXR
Loculated (cannot tap w/thoracentesis)

Thoracentesis

Unilat effus'n (bilat asymm)

Pleuritic pain, F

Pleural fluid ® LDH, pro, cell count, differential, mibi, cytol

Light's criteria 4 exudate

Pleural pro / serum pro > 0.5
Pleural LDH / serum LDH > 0.6
Pleural LDH > 200IU/L

Appearance

Clear/ yellow ® transudate

Straw ® trans/ exudate

Blood-tinge ® exudate (excl. traumatic tap)

Milky ® (pseudo)chylothorax

Bloody ® trauma, infarct, malig

Pus ® empyema

Anchovy ® amoebic liver abscess rupture intro pleural sp

Biochem

Gluc + pH: ¯ in exudate (pH < 7.3, gluc < 5.3) - eg. empyema, rheum pleuritis, malig

Adenosine deaminase: TB > 45 U/mL (also empyema, rheum pleuritis)

Amylase: in pancreatitis, oeso rupture

TG/ chylomicrons: chylothorax

Chol (+ ¯ TG): pseudochylothorax (fr LT transudate)

Cell count + differential

Transudate WBC < 1000/mm3

Exudate WBC > 1000/mm3

Acute inflam neutrophil (eg parapneumonic effus'n)

TB/ Malig lymphocyte

Cytol

+ve yield for 3 sep pleural effusion spec's for Pt w/malig = 70-80%

Mibi

Bact Gram smear, culture
AFB smear, culture
Other - eg. fungus

Additional

F - infection, collagen vasc dis, infarct'n

Hx + P/E - infection, collagen vasc dis, DVT, pleural rub

If no obvious chest infec'n + amylase ® CT ab

Malig - CT chest (parenchymal lesions) + Bronchoscopy (¯ yield if no lesions on radiol)

Biopsy (Percutaneous Pleural)

Exduative pleural effus'n with no obvious aetiology (after above Ix)
Usu TB, neoplasm

Thoracoscopy

Isolated exudative pleural eff (+ no obvious aetiology after above Ix)

MANAGEMENT

Transudate

Address systemic issue

Parapneumonic effus'n + empyema

Stages

Pleuritis sicca: pneum ® extend to pleura ® pleuritis (± pleura eff)

Exdudative: "UPE - uncomplicated parapneumonic effusion", inflam med ® cap perm ® exudate (fluid: clear, sterile, neutrophil, pH N, LDH < 1000U)

Fibropurulent: "CPE - complicated…", no appropriate ABX ® inv pleura ® locul'n due to fibrin clot/membr (fluid: turbid, infective agent, pH < 7.2, LDH>1000)

Organisation: fibroblasts ® pleura ® thick non-elastic pleural peel (trapped lung) = perm func disab'y

Systemic ABX (earlier better)

Chest tube drainage - not UPE, for CPE, empyema (loculation: US/CT guide)
Intrapleural fibrinolytic agents - CPE with locul'n, empyema, can avoid (f)
Therapeutic thorascopy (adhesionolysis, fibrinolysis) - failed Tx after ABX, tube, fibrinolytics

Thoracotomy w/decortication (rare) - chronic post-pneumonic empyema w/no response to ABX/tube

Other causes of exudate effus'n

TB effus - TB meds

Pul emb - anti-coag

Collagen vasc dis - Tx

Chylothorax - thoracic duct repair, med-chain TG diet if chronic

Pseudochylothorax - u'lying cause

Malig effus - observe, Tx ca, thoracentesis (<1.5L/time), if repeated chest tap ® chemical pleurodesis

CA BRONCHUS

EPIDEMIOLOGY

HK: 65% ca lung deaths > 60yo
M: > 90% chronic smokers; lung ca 1/3 M deaths
F: 50% non-smokers (adenocarcinoma = 60%)

Passive smoking: RR = 2 (cf. active = 10-20)

Diet: ¯ fruit/ veg, Vit A

Wok: oil emission at high T

Other: kerosene stove, incense, radon, TB, HLA Ag, k-ras oncogene, p53 TSG

PATHOLOGY

	M (%)	F(%)
SQ (squamous cell)	38	15
AD (adenocarcinoma)	32	60 *
LA (large cell)	15	10
SM (small cell)	15	15

Note: AD in F, 'ing AD in M (will o'take SQ)

CLINICAL FEATURES

1. CXR abn only (5%)
2. Constitutional symps	- Malaise, ¯ app/ BW
3. Primary lesion
a) Bronchial mucosa ulcer'n	- Cough, sputum, haemoptysis
b) Obstruct'n: partial (complete)	- Wheeze, pneum (dyspnoea)
4. Intrathoracic spread
a) Along lymph ® both lungs (lymphangitis carcinomatosis)	- Cough, dyspnoea
b) Pleura/ Pleural effusion	- Chest pain, dyspnoea
c) Pericardial (cardiac tamponade)	- Dyspnoea
d) SVCO	- Dyspnoea, stridor, dysphagia, facial swell
e) L recur laryngeal n	- Hoarse (hooks under aortic arch)
f) Brachial plexus (C8, T1,2) + cervical symp ganglion (Horner)	- Pain: shoulder/ arm - Sweat 1side/ face, ptosis, constrict pupil
g) Oeso	- Dysphagia
h) Chest wall/ rib	- Chest pain, swell
5. Distant metastases
a) Lymphatics	- Mass: neck, supraclav fossa
b) Blood
Skin Bone Liver Brain Adrenals - common, clinically silent	- Skin mass - Bone pain (back, pelvis) - Epigastric distending discomfort - Hemiplegia, focal epilepsy
6. SNMS (Systemic Non-Metastatic Syn) *
a) CT: clubbing, HPOA	- Arthralgia, pain extremities
b) Ectopic H
ADH (¯ Na+)	- Confused, weak
ACTH (¯ K+)	- Weak
PCP ( Ca++) - PT-like peptide	- Polyuria, thirst, confused
Bone metastases most common cause for Ca++ in ca lung
c) NM
Encephalopathy	- Dementia, confusion
Cerebellar degeneration	- Ataxia, clumsiness
Peripheral neuropathy	- Paraesthesia, weakness
Myasthenia-like (Eaton-Lambert)	- Weakness
Dermatomyosis	Looks like sunburn, weakness, skin rash

* SNMS: 10% ca lung, 1^st symp of occult tumour \ specific, effective Tx of symptoms

CELL TYPE CHARACTERISTICS

	SQ	AD	LA	SM
Smoking	+++	+	+	+++
Sit	C	P	P	C
Pleural effusion	+	+++	+++	++
Growth	+	+	+	+++
Metastatic pot	+	++	++	+++
SNMS	+	+	+	+++
Chemo/ Rad	+	+	+	+++

INVESTIGATIONS

DIAGNOSIS

1. CXR

Uniat hilar enlargement
Peripheral tumour mass
Collapse
Elevated hemidiaphragm
Pleural effusion
Mediastinal LN
Pancoast tumour (apical w/ rib erosion)
Carinomatosis

2. Cytology

Sputum
Bronchial wash + brush
Pleural fluid
Transthoracic FNA (LN, skin, nodules)

3. Histol

Bronchoscopic biopsy (trans/bronchial)
Pleura
LN (direct, mediastinoscopy)
Other metastases (skin, liver)
Exploratory thoracotomy
Rib erosion

STAGING

Blood test
Bronchoscopy
Biopsy - pleura, LN
CT thorax/ upper ab (liver, adrenal)
As indicated - CT/MRI brain, bone scan, PET scan
Cardiac/ lung func'n

MANAGEMENT

Surgery

Best chance cure (minority)
Dep: (1) Tumour: early stage, NSC (2) Pt: CP func, performance status

Rad'n

Radical/ cure: single tumour, if cannot do surg due to med reasons
Palliative: metastasis (bone, cerebral, SC), SVCO

Chemo

cyclical combo chemo (2-4 cse, 3-4w apart)

SC: 4-6 cse, 60-90% response (b/c fasting growing cf. NSC), eg. cisplatin + VP16, CAV, limited dis use chemo + rad (prophylactic cranial rad if complete response), survival 14-18m (vs. no Tx 3m)

NSC: adv/ metastatic cases, 30-60% partial response (PR) ( relapse), survival 2-3m only, eg. MIP/ cisplatin + VP16 (PR 40%, cheaper), new: taxol/ taxotere/ gemcitabine (PR 60%, expensive)

S/E: alopecia, mouth ulcer, nausea + v, diarrhoea, BM suppression (all cytokines)
Spec S/E: nephrotoxic (cisplatin), cardiac (adriamycin)

Multimodal

rad + CT ± surg

locally advanced cases

Supportive

Hospice
Analgesic (opioid) - symptomatic: cough suppression, thoracentesis, pleurodesis
Psychosocial

PROGNOSIS

Few: stage 1 NSC - after surg 50% at 5y (most 10% at 5y)

85% ca lung ® active smoking (\ anti-tob prg)