This document discusses lung tumors, specifically bronchogenic carcinoma (lung cancer). It notes that bronchogenic carcinoma makes up 90-95% of primary lung tumors and is the most common cause of cancer death. The main risk factor for developing lung cancer is cigarette smoking, as smoking increases risk 10-fold and heavy smoking increases risk 20-fold. The document further describes the classification, clinical features, spread, and pathology of various types of lung cancer including squamous cell carcinoma, adenocarcinoma, small cell carcinoma, and large cell carcinoma.

1. Lung tumoursLung tumours
Primary tumours (arising in the lungs)Primary tumours (arising in the lungs)
 Broncogenic carcinoma (90 – 95%)Broncogenic carcinoma (90 – 95%)
 Bronchial carcinoids – 5%Bronchial carcinoids – 5%
 HamartomaHamartoma
 Mesenchymal tumoursMesenchymal tumours
 BenignBenign
 Fibroma, Leiomyoma, lipoma, haemangioma & chondromaFibroma, Leiomyoma, lipoma, haemangioma & chondroma
(rare)(rare)
 MalignantMalignant
 Fibrosarcoma, leiomyosarcoma & othersFibrosarcoma, leiomyosarcoma & others
Secondary metastatic tumours – is the commonest lung tumourSecondary metastatic tumours – is the commonest lung tumour

2. Bronchogenic carcinomaBronchogenic carcinoma
 Bronchogenic carcinoma is a malignant neoplasm of the lung arisingBronchogenic carcinoma is a malignant neoplasm of the lung arising
from the epithelium of the bronchus or bronchiole.from the epithelium of the bronchus or bronchiole.
 Lung cancer is the most frequent cause of cancer death andLung cancer is the most frequent cause of cancer death and
accounts for 14% of all cancer diagnoses and 28% of all canceraccounts for 14% of all cancer diagnoses and 28% of all cancer
deaths.deaths.

3. Etiology & PathogenesisEtiology & Pathogenesis
Risks of developing lung ca areRisks of developing lung ca are
1. Cigarette smoking1. Cigarette smoking
• Most important & common etiological factor in theMost important & common etiological factor in the
development of lung cancer.development of lung cancer.
• Evidences are Statistical, clinical & experimentalEvidences are Statistical, clinical & experimental
• Statistical - Smokers have 10 fold greater risk than nonStatistical - Smokers have 10 fold greater risk than non
smokers & heavy smokers 20 fold greater risksmokers & heavy smokers 20 fold greater risk
• Clinical – histological changes like hyperplasia,Clinical – histological changes like hyperplasia,
squamous metaplasia & dysplasia can be seen insquamous metaplasia & dysplasia can be seen in
smokerssmokers

4. CarcinogensCarcinogens
Cigarette smoke contains a number of proven carcinogensCigarette smoke contains a number of proven carcinogens
in both the particulate and gaseous phase including:in both the particulate and gaseous phase including:
-Aromatic Hydrocarbons-Aromatic Hydrocarbons
-Nitrosamines, Nitrosonornicotine-Nitrosamines, Nitrosonornicotine
-Polonium-Polonium

5. 2. Industrial Exposure2. Industrial Exposure
 Radiations of all typeRadiations of all type
 Workers withWorkers with
 -Asbestos-Asbestos
 -Coal-Coal
 -Nickel-Nickel
 -Chromates-Chromates
 -Mustard Gas-Mustard Gas
 -Iron-Iron
 - Arsenic- Arsenic
3. Air Pollution – carcinogens in pollutant air3. Air Pollution – carcinogens in pollutant air

6. 4. Genetic factors4. Genetic factors
It is suggested that there is genetic predisposition to lungIt is suggested that there is genetic predisposition to lung
cancercancer
5. Scarring5. Scarring
Some lung cancer arise in the vicinity of pulmonary scarsSome lung cancer arise in the vicinity of pulmonary scars
(Infarct & TB) & are termed scar cancer(Infarct & TB) & are termed scar cancer

7. Clinical featuresClinical features
Cough, sputum production, weight loss, anorexia, fatigue,Cough, sputum production, weight loss, anorexia, fatigue,
dyspnea, hemoptysis, and chest paindyspnea, hemoptysis, and chest pain
Obstruction may produce focal emphysema, atelectasis,Obstruction may produce focal emphysema, atelectasis,
bronchiectasis, or pneumoniabronchiectasis, or pneumonia

8. MorphologyMorphology
 They arise in the lining epithelium of major bronchi usually close toThey arise in the lining epithelium of major bronchi usually close to
hilus of lungshilus of lungs
 Starts as small mucosal lesion & then mayStarts as small mucosal lesion & then may
 Form intraluminal massForm intraluminal mass
 Invade the bronchial mucosaInvade the bronchial mucosa
 Form large bulky massesForm large bulky masses
 Bulky tumours may show focal areas of Hg, necrosis, softening &Bulky tumours may show focal areas of Hg, necrosis, softening &
cavitaioncavitaion


9. A progression of histologic changes in the lung occurs from smokingA progression of histologic changes in the lung occurs from smoking
fromfrom
 (1) proliferation of basal cells,(1) proliferation of basal cells,
 (2) to development of atypical nuclei with prominent nucleoli,(2) to development of atypical nuclei with prominent nucleoli,
 (3) to stratification,(3) to stratification,
 (4) to development of squamous metaplasia and(4) to development of squamous metaplasia and
 (5) carcinoma in situ, to(5) carcinoma in situ, to
 (6) invasive carcinoma.(6) invasive carcinoma.

10. Classification of Bronchogenic CarcinomaClassification of Bronchogenic Carcinoma
According to morphology WHO has classified lung cancer as follow:According to morphology WHO has classified lung cancer as follow:
1.1. Squamous cell carcinoma (25-40%)Squamous cell carcinoma (25-40%)
2.2. Adenocarcinoma (25-40%)Adenocarcinoma (25-40%)
a.a. bronchial derivedbronchial derived
b.b. bronchioloalveolar carcinomabronchioloalveolar carcinoma
3.3. Small cell carcinoma (20-25%)Small cell carcinoma (20-25%)
4.4. Large cell carcinoma (10-15%)Large cell carcinoma (10-15%)

11. Squamous cell CarcinomaSquamous cell Carcinoma
 It is commonly found in menIt is commonly found in men
 Closely related with smoking.Closely related with smoking.
 Approximately 2/3Approximately 2/3rdrd
of these tumors are centrally located and tend toof these tumors are centrally located and tend to
expand against the bronchus, causing extrinsic compression.expand against the bronchus, causing extrinsic compression.
 These tumors are prone to undergo central necrosis and cavitation.These tumors are prone to undergo central necrosis and cavitation.
 SCCA tends to metastasize later than does ACA.SCCA tends to metastasize later than does ACA.
 SCCA may be more readily detected on sputum cytology than ACA.SCCA may be more readily detected on sputum cytology than ACA.

12. MicroscopicallyMicroscopically
 Well differebtiated to anaplasticWell differebtiated to anaplastic
 keratinization i.e. production of keratin pearls, stratification, andkeratinization i.e. production of keratin pearls, stratification, and
intercellular bridge formation are exhibited.intercellular bridge formation are exhibited.

13. This isThis is
anotheranother
sqamoussqamous
cellcell
carcinomacarcinoma
that extendsthat extends
from hilumfrom hilum
to pleura.to pleura.
The blackThe black
areasareas
representrepresent
anthracoticanthracotic
pigmentpigment
trapped intrapped in
the tumor.the tumor.

14. This is a squamous cellThis is a squamous cell
carcinoma of the lungcarcinoma of the lung
that is arising centrallythat is arising centrally
in the lung (as mostin the lung (as most
squamous cellsquamous cell
carcinomas do). It iscarcinomas do). It is
obstructing the rightobstructing the right
main bronchus. Themain bronchus. The
neoplasm is very firmneoplasm is very firm
and has a pale white toand has a pale white to
tan cut surface.tan cut surface.

15. This is a largerThis is a larger
squamous cellsquamous cell
carcinoma in which acarcinoma in which a
portion of the tumorportion of the tumor
demonstrates centraldemonstrates central
cavitation, probablycavitation, probably
because the tumorbecause the tumor
outgrew its bloodoutgrew its blood
supply.supply.

16. This is the microscopic appearance of squamous cellThis is the microscopic appearance of squamous cell
carcinoma with nests of polygonal cells with pink cytoplasmcarcinoma with nests of polygonal cells with pink cytoplasm
and distinct cell borders. The nuclei are hyperchromatic .and distinct cell borders. The nuclei are hyperchromatic .

17. In this squamous cell carcinoma at the upper left is a keratin pearl. AtIn this squamous cell carcinoma at the upper left is a keratin pearl. At
the right, the tumor is less differentiatedthe right, the tumor is less differentiated

18. Adenocarcinoma (ACA)Adenocarcinoma (ACA)
 It is derived from the mucus-producing cells of the bronchial epitheliumIt is derived from the mucus-producing cells of the bronchial epithelium
in the terminal bronchioles or alveolar walls .in the terminal bronchioles or alveolar walls .
 It is the most common type of lung cancer in women and in non-It is the most common type of lung cancer in women and in non-
smokers.smokers.
 Male female ratio is equalMale female ratio is equal
 Most of ACA tumors (75%) are peripherally located.Most of ACA tumors (75%) are peripherally located.
 It tends to metastasize earlier than squamous cell carcinoma (SCCA)It tends to metastasize earlier than squamous cell carcinoma (SCCA)

19. Microscopic featuresMicroscopic features
 Gland formation with mucin productionGland formation with mucin production
 Consist of cuboidal to columnar cells with adequate to abundant pinkConsist of cuboidal to columnar cells with adequate to abundant pink
or vacuolated cytoplasmor vacuolated cytoplasm

20. Slide 16.48

21. moderately differentiated adenocarcinoma - peripheral lung cancers that have not
metastasized can be easily resected

22. Microscopically, the bronchioloalveolar carcinoma is composed of columnar cellsMicroscopically, the bronchioloalveolar carcinoma is composed of columnar cells
that proliferate along the framework of alveolar septae. The cells are well-that proliferate along the framework of alveolar septae. The cells are well-
differentiated. These neoplasms in general have a better prognosis than mostdifferentiated. These neoplasms in general have a better prognosis than most
other primary lung cancersother primary lung cancers

23.  This is a peripheralThis is a peripheral
adenocarcinoma of the lung.adenocarcinoma of the lung.
Adenocarcinomas and large cellAdenocarcinomas and large cell
anaplastic carcinomas tend toanaplastic carcinomas tend to
occur more peripherally in lung.occur more peripherally in lung.
 Adenocarcinoma is the one cellAdenocarcinoma is the one cell
type of primary lung tumor thattype of primary lung tumor that
occurs more often in non-occurs more often in non-
smokers and in smokers whosmokers and in smokers who
have quit.have quit.
 If this neoplasm were confined toIf this neoplasm were confined to
the lung (a lower stage), thenthe lung (a lower stage), then
resection would have a greaterresection would have a greater
chance for cure.chance for cure.
 The solitary appearance of thisThe solitary appearance of this
neoplasm suggests that the tumorneoplasm suggests that the tumor
is primary rather than metastatic.is primary rather than metastatic.

24. Small cell lung cancerSmall cell lung cancer
 About 80% are centrally located.About 80% are centrally located.
 The disease is characterized by a very aggressive tendency toThe disease is characterized by a very aggressive tendency to
metastasize.metastasize.
 It is highly malignant .It is highly malignant .
 It is strongly associated with smoking (99%).It is strongly associated with smoking (99%).
 It spreads very early to mediastinal lymph nodes and distantIt spreads very early to mediastinal lymph nodes and distant
sites, especially bone marrow and brain.sites, especially bone marrow and brain.
 Usually produce paraneoplstic syndromeUsually produce paraneoplstic syndrome

25.  Arising centrally in this lung andArising centrally in this lung and
spreading extensively is a smallspreading extensively is a small
cell anaplastic (oat cell)cell anaplastic (oat cell)
carcinoma.carcinoma.
 The cut surface of this tumor hasThe cut surface of this tumor has
a soft, lobulated, white to tana soft, lobulated, white to tan
appearance.appearance.
 The tumor seen here has causedThe tumor seen here has caused
obstruction of the main bronchusobstruction of the main bronchus
to left lung so that the distal lungto left lung so that the distal lung
is collapsed.is collapsed.
 Oat cell carcinomas are veryOat cell carcinomas are very
aggressive and oftenaggressive and often
metastasize widely before themetastasize widely before the
primary tumor mass in the lungprimary tumor mass in the lung
reaches a large size.reaches a large size.

26. MicroscopicallyMicroscopically
 Sheets or clusters of cells with dark nuclei and very little round orSheets or clusters of cells with dark nuclei and very little round or
oval cytoplasm.oval cytoplasm.
 This "oatlike" appearance under the microscope provides the termThis "oatlike" appearance under the microscope provides the term
oat cell carcinoma to this disease.oat cell carcinoma to this disease.
 Few cells are spindle or polygonal shape too.Few cells are spindle or polygonal shape too.

27. Large cell carcinomaLarge cell carcinoma
 It is undifferentiated (anaplastic) carcinomaIt is undifferentiated (anaplastic) carcinoma
 These tumors tend to occur peripherally and may metastasizeThese tumors tend to occur peripherally and may metastasize
relatively early.relatively early.
MicroscopicallyMicroscopically ,,
 Anaplastic, pleomorphic cells with vesicular or hyperchromaticAnaplastic, pleomorphic cells with vesicular or hyperchromatic
nuclei and abundant cytoplasm.nuclei and abundant cytoplasm.
 There are a large number of multinucleated giant cells.There are a large number of multinucleated giant cells.

28. Paraneoplastic syndromes in bronchogenic Ca.Paraneoplastic syndromes in bronchogenic Ca.
 ACTH- Cushings syndromeACTH- Cushings syndrome
 Serotonin – Carcinoid syndromeSerotonin – Carcinoid syndrome
 Gonadotropins – GynaecomastiaGonadotropins – Gynaecomastia
 ADH – HyponatraemiaADH – Hyponatraemia
 Parathormone – HypercalcaemiaParathormone – Hypercalcaemia
 Calcitonin – hypocalcaemiaCalcitonin – hypocalcaemia

29. SpreadSpread
Invasion or local spreadInvasion or local spread
 May infiltrate the peribronchial tissue, mediastinum, pleural cavity orMay infiltrate the peribronchial tissue, mediastinum, pleural cavity or
into peritoneuminto peritoneum
MetastasisMetastasis
 Lymphatic spread – trachea, bronchial & mediastinal nodesLymphatic spread – trachea, bronchial & mediastinal nodes
 Blood spread – Liver, brain, bones & adrenal are common. No organBlood spread – Liver, brain, bones & adrenal are common. No organ
or tissue is sapredor tissue is sapred

30. Secondary Pathology associated with lung cancerSecondary Pathology associated with lung cancer
 Bronchial ObstructionBronchial Obstruction
 Partial obstruction- EmphysemaPartial obstruction- Emphysema
 Total obstruction- AtelectasisTotal obstruction- Atelectasis
 Severe suppurative or ulcerative bronchitis or bronchiectasisSevere suppurative or ulcerative bronchitis or bronchiectasis
 Pulmonary abscessPulmonary abscess
 Superior venacava syndromeSuperior venacava syndrome
 Pericarditis and pleuritisPericarditis and pleuritis
 Systemic- Paraneoplastic syndromeSystemic- Paraneoplastic syndrome

31. Secondary metastatic tumours of lungsSecondary metastatic tumours of lungs
 Both carcinomas & sarcomas of any site in the body frequentlyBoth carcinomas & sarcomas of any site in the body frequently
spread to the lungsspread to the lungs
 Via lymphatics or blood or direct continuity (oesophageal,Via lymphatics or blood or direct continuity (oesophageal,
mediastinal)mediastinal)
 Usually multiple discrete nodules are scattered throughout the lungsUsually multiple discrete nodules are scattered throughout the lungs

32. Commonly suggested investigations for diagnosis of theCommonly suggested investigations for diagnosis of the
diseasedisease
- Sputum for cytologySputum for cytology
- Chest X-rayChest X-ray
- FNAC/biopsy of tumor mass or secondary lymph nodesFNAC/biopsy of tumor mass or secondary lymph nodes
- BronchoscopyBronchoscopy
- CT scan/MRICT scan/MRI

37.  Classify the lung tumoursClassify the lung tumours
 Give the etiopathogenesis of Bronchogenic carcinomaGive the etiopathogenesis of Bronchogenic carcinoma
 Classify bronchogenic carcinomaClassify bronchogenic carcinoma
 Give the morphology of bronchogenic squamous cellGive the morphology of bronchogenic squamous cell
carcinomacarcinoma