1. Damian Gimpel Waikato Cardiothoracic Unit
Benign lung tumours
Damian Gimpel
Waikato Cardiothoracic Unit

2. Arises from 1950’s  Liebow Classification
Essence of classification is origin of growth
If any pulmonary nodule can’t be proven to be benign  removed

3. Classification

4. Hamartomas Most common benign tumour Roughly 8% of pulmonary neoplasms
Asymptomatic
Incidentalomas post routine CXR
Male 2:1
30-60 years old
Location – Peripheral (Note – Can be bronchial)

5. Hamartomas Mostly solitary pulmonary nodules  rarely multiple nodules
well-circumscribed lesions - 1 and 2 cm in diameter
Calcification may be present but may not be obvious on the plain chest radiograph.
CT  calcification and fat  popcorn calcification in a well demarcated lesion is highly suggestive of a benign neoplasm.

6. Hamartomas

7. Clear cell tumour Histology  resemble metastatic renal cell carcinoma
Characterized by sheets and cords of polygonal cells separated by a prominent brovascular stroma.
Eosinophilic cytoplasm
The nuclei are characteristically bland and vary in size; mitoses are usually absent.
Peripherally located, and are typically 2 cm or less in size.
Immunohistochemical analysis  definitive diagnosis

8. Germ cell tumour Benign teratomas  rare
They occur generally in young patients
May occasionally manifest with trichoptysis
(coughing out hair)

9. Germ cell tumour

10. Epitheloid - AAH Atypical adenomatous hyperplasia (AAH)
Also known as  alveolar cell hyperplasia, atypical alveolar hyperplasia,
or bronchioloalveolar cell adenoma
One or more small, asymptomatic ground-glass opacities in the
periphery of the lung.
Lesion is often seen adjacent to or within the same mass of a bronchoalveolar carcinoma (BAC).
Histologically  proliferation of minimally atypical cuboidal type II pneumocytes.

11. Epitheloid - AAH
Clinical differentiation between AAH and true BAC is essentially impossible

12. Mesodermal ORIGINS

13. Sclerosing haemangioma
middle-aged women
Again asymptomatic  Peripheral
well-circumscribed nodule that may be partially calcifi ed
Grossly, the lesion may appear hemorrhagic.
tumors range in diameter from 1 to 8 cm.
Radiographically  well-defined, homogeneous, Round or oval masses in all patients.
Histology  four major patterns in the same tumor: solid, papillary, vascular and sclerotic

14. Sclerosing haemangioma
Newer immunohistochemical research  primitive respiratory epithelial cell, not a mesenchymal cell.
Reclassification  alveolar pneumocytoma

15. hemagiopericytoma Wide range of age presentation
2 to 15 cm in diameter.
hemoptysis, dyspnea, and chest pain.
characterized by its vascularity and the peritheliomatous arrangement of the tumor cells.
There are well preserved vascular channels
Questionable as to whether this is a true or malignant lesion

16. Granular cell / Schwannoma
solitary pulmonary nodules
may occur in the trachea or main stem bronchi, occasionally as multiple lesions.
M:F = 1
30-40 years of age
younger than that typically of patients with endobronchial malignancies.
Patients usually present with cough or other symptoms suggestive of bronchial obstruction

17. Bronchopulmonary fibroma
Tracheobronchial tree or within the pulmonary parenchyma.
Fibromas occurring in the pulmonary parenchyma usually are
asymptomatic and appear as well-circumscribed nodules
without specific characteristics to differentiate them from
other lesions.
Wedge excision is both diagnostic and curative
Histology  abundance of collagen and bland spindle
cells

18. lipoma
Bronchial in origin  submucosal fat that is present between cartilaginous rings.
Parenchymal lipomas are rare.
The symptoms and signs  Location
Most common  manifestations of obstruction
predominate with the larger lesions.
Usually pedunculated tumors with a narrow stalk that are covered by normal respiratory mucosa.
Can also arise in the visceral and parietal pleura (RARE)

19. leiomyoma Rare  Most common soft tissue tumor of the lung.
Smooth muscle fibers.
Women account for two thirds of the affected patients  AGE 35
solitary, peripheral, pulmonary nodules  Asymptomatic.
no specific characteristics that distinguish this lesion from other pulmonary nodules.

20. Other TYPES

21. Bronchial associated lymphoid tumours (BALT)
Histology  small lymphoid cells interspersed among clusters of plasma cells
The tumor usually has a nodular appearance because of its tendency to localize around lymphoid follicles.
Post removal  Lymphoma workup
If no other evidence of lymphoma exists  out patient follow

22. Other
pulmonary meningioma
ganglionoma
lymphangioma

23. diagnosis Incidentalomas:
Most benign tumors manifest as asymptomatic nodules found
on a routine chest radiography or CT performed for other
Reasons.
Most are peripheral
Small percentage of benign lesions are in an endobronchial location and may be manifested by lobar or whole lung collapse, hyperinflation
secondary to a ball-valve mechanism, cough, pneumonia, or,
occasionally, hemoptysis.

24. bronchoscopy when there is an endobronchial lesion
diagnosis
bronchoscopy when there is an endobronchial lesion
However! Most are Peripheral
NEED TISSUE!

25. no criteria are absolute
diagnosis
no criteria are absolute
a number of factors point to a benign diagnosis.

26. diagnosis
Lesions in non smokers, younger than 30 years of age are extremely unlikely to be Malignant Timing  if it has not changed in size over 2 years or longer, it is also generally safe to consider it benign, Dense or central calcification is considered to be a reliable indicator that a lesion is benign, as is popcorn calcification, which suggests a hamartoma.

27. diagnosis
Positron emission tomography  there is clearly significant overlap between the two groups A specific benign diagnosis is made only 10% of the time by bronchoscopy 67% of the time by TTNB.

28. diagnosis
only a definitive benign diagnosis by cytology or microbiologic examination
Specific benign findings include cartilage or fat suggestive of a hamartoma or fungal elements or acid-fast organisms diagnostic of an infectious process.

29. management Simple excision of a benign lesion is curative.
Excision may be done without the need for an anatomic resection, although the type of resection is obviously dependent on the location of the lesion.
Conservation of lung tissue is paramount.

30. management
Surgical therapy of benign lesions located in the parenchyma is mandated largely by the fact that the diagnosis usually cannot be definitively established until the lesion isremoved.