Bronchogenic Carcinoma

1. BRONCHOGENIC CARCINOMA

2. Learning Objectives
At the end of this presentation, you should
know
• Different histological types of bronchogenic
carcinoma
• Gross appearance of each type
• Microscopic appearance of each type.
• Differences between each type.

3. BRONCHOGENIC CARCINOMA
There are four main histologic types of primary bronchogenic
carcinoma : -
1. Squamous cell carcinoma
2. Adenocarcinoma
3. Bronchioalveolar carcinoma
4. Small cell carcinoma
5. Large cell carcinoma

4. SQUAMOUS CELL CARCINOMA
GROSS :
• The tumour is often hilar or
central arising from a large
bronchus
• Variable size and invades
adjacent lung parenchyma
• Cut surface of tumour shows
extensive necrosis and cavitation
C/S grey-white fleshy tumour in bronchus at its
bifurcation and occluding lumen partly (arrow)
The tumour is seen extending directly into
adjacent lung parenchyma and hilar nodes

5. SQUAMOUS CELL CARCINOMA
MICROSCOPY :
• Varying grades of differentiation
from well-differentiated with
keratinisation to poorly
differentiated
• Intercellular bridges or keratinisation
often seen in well differentiated
• Edge of tumour often shows
squamous metaplasia, epithelial
dysplasia and carcinoma insitu
Islands of invading malignant squamous cells
are seen. A few well-developed cell nests
with keratinisation are evident.

6. ADENOCARCINOMA
GROSS :
• Classically peripheral tumors which
does not form a cavitary lesion
• Single or multiple solid firm yellow-
white nodule or mass which may invade
pleura
Peripheral tumor

7. ADENOCARCINOMA
MICROSCOPY :
• Invasive malignant epithelial tumor
with glandular differentiation or mucin
production by tumor cells
• Various patterns- acinar, lepidic,
papillary, micropapillary, and solid with
mucin formation
• Tumors show desmoplastic reaction,
lymphovascular or pleural invasion
with areas of necrosis
Gland-forming adenocarcinoma

8. BRONCHIOALVEOLAR CARCINOMA
• Variant of adenocarcinoma
• Growth along existing alveolar walls ( lepidic
pattern)
• No association with smoking

9. Small cell carcinoma
GROSS :
• The tumour is frequently hilar or
central in location
• The tumour appears as a nodule
measuring 1-5 cm in diameter with
ulcerated surface
• Cut surface - tumour is yellowish-
white with areas of necrosis and
haemorrhages

10. SMALL CELL CARCINOMA
MICROSCOPY :
• Tumour cells -uniform, small,
larger than lymphocytes
• Dense round or oval nuclei
having diffuse chromatin,
inconspicuous nucleoli and
scanty cytoplasm
• Tumour cells arranged in cords,
aggregates and ribbons, or
around small blood vessels
forming pseudorosettes The tumour cells are arranged in sheets,cords,
aggregates and at places form pseudorosettes.
The individual tumour cells are small, uniform,
lymphocyte-like with scanty cytoplasm.

11. LARGE CELL CARCINOMA
GROSS :
• The tumor is peripheral with
lobulated apperance and
bulging borders
• Cut surface shows gray white
"fish flesh" areas with areas of
hemorrhage and necrosis

12. LARGE CELL CARCINOMA
MICROSCOPY :
• Tumour cells - large, polygonal
and anaplastic cells growing in
sheets or solid nests
• No clear adenocarcinoma,
squamous or neuroendocrine
morphology
• Moderately abundant cytoplasm,
well defined cell borders,
vesicular nuclei, prominent
nucleoli
• Foci of central necrosis and
hemorrhage may be present
The tumor cells are pleomorphic and show no
evidence of squamous or glandular differentiation.