Small Lung Biopsies

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Small Lung Biopsies

• Richard Bishop
• Histopathology
• Leeds General Infirmary

2
Introduction

• Small ones are more tricky
• Less information on which to base your critical
  decisions
• Cover some of particularly difficult areas

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Some major distinctions to make

• benign - malignant
• epithelial - not epithelial
• SCLC - NSCLC
• SCC adenocarcinoma
• Degree of certainty with which you make these
  diagnostic decisions is tempered by the gravity
  of diagnosis eg nsc v sc rx, therefore need to
  have basic knowledge of important distinctions as
  far as clinicians go

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Difficult areas 1

• How much is enough?
• When do I need Immunos?
• Largish neuroendocrine looking cells
• Are they SCLC, NSCLC or large cell NEC?
• Dead tumour cells?
• Tumour necrosis or necrotic infection/infarction

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Difficult areas 2

• Inflamed material
• Is it infection or tumour?
• benign looks malignant
• Crushed lymphocytes (vs SCLC) or glands (vs
  NSCLC), in situ disease, very reactive
  epithelium
•  
• malignant looks benign
• lymphomatous infiltrate, crushed sclc,  

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Difficult areas 3

• worrying things
• necrotic material, para/orthokeratotic material,
  big irregular nuclei
• SCLC vs NSCLC
•  
• SCC vs adenoCa - sometimes relevant especially if
  ?1y ?2y
• When to mention 2y should be considered

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Some Other Entities

• Salivary gland type tumours
• Carcinoid
• Inflammation/infection
• Adenomas
• Papillomas

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Good references for tumours in Lung

• WHO book (histological typing of tumours of lung
  and pleura)
• AFIP fascicle
• Corrins Pathology of the Lungs
• Group 3 consultants!

9
Some things not to forget

• Is there enough for diagnosis?
• Clinical features
• Tumour heterogeneity
• Primary vs Secondary
• False negative better than false positive ie have
  a high threshold for confident diagnosis