Lecture16

Question 1

Describe the epidemiology of lung cancer?

Answer 1

Most common causes of cancer death, yet 5th most common cancer.

Question 2

What is the median age for patients?

Answer 2

50-70years in age. Male predominance, predominantly through smoking, yet it has been decreasing.

Question 3

Describe a strong link to lung cancer?

Answer 3

Smoking at around 85%.

Question 4

Describe the pathogenesis?

Answer 4

Strong link to smoking. Subdivide lung cancer based on the pathology: squamous and small cell cancer. The mutations in p53 etc. There is genetics which can increase/decrease risk of lung cancer.

Question 5

Describe the pathology reports of patients with lung cancer?

Answer 5

Based on morphology, and different molecular changes between different morphological types of lung cancer. 20-25% are Small Cell Lung Cancer and 70-75% are Non-Small Cell Lung Cancer.

Question 6

What does the pathology reflect?

Answer 6

The cell of origin. Different patterns of mutation. Important as it has implications both clinically and therapuetically.

Question 7

Describe the importance of lung cancer classification?

Answer 7

For a long time different morphologic classifications, now we are recognising different pattern on gene mutations. Significant therapeutic implications. IN NSCLC there are two inhibitors: erlotinib and gefitinib are involved in tyrosine kinase inhibition. This will stop the EGF pathway.

Question 8

Describe the clinicopathological features of Lung Cancer 1?

Answer 8

A lot of the presentation will be of local effects; lesion in the lung i.e. coughing up of blood. If the lesion is blocking the airway, could cause pneumonia. If it is a local spread, you may get a pleural effusion (fluid in the pleural space) or nerve entrapment. Or if spreads to the mediastinum could get pressure on the SVC (present with paralysis of vocal cords - so forcefulness of voice).

Question 9

Describe SVC obstruction?

Answer 9

Mediastinal mass on XRAY. The JVP will be engorged and distended, other venous networks will open up. Oedema, facial fullness and congestion of the face. A test is to put the arms above the head, and increases the obstruction, blocked off all the venous return - get red in the face.

Question 10

Describe Horner’s syndrome?

Answer 10

Nerve impinged on by the tumour, so get drooping of the eye. Often asymptomatic. Hoarseness in the voice, due to recurrent, laryngeal nerve being impinged. If you try and get them to do a high E, it is very hard for them to do.

Question 11

Describe the clinicopathological features of Lung Cancer 2?

Answer 11

Symptoms in the initial presentation may be due to metastatic spread. The patient may present with pathological fracture, bone pain, or neurological presentation. The presentation might be from the secondary spread, rather than from primary lesion. Do a chest X-RAY to find the primary lung lesion.

Question 12

Describe the clinicopathological features of Lung Cancer 3?

Answer 12

Often known as paraneoplastic features.
Small cell cancers produce endocrine factors that can cause a systemic syndrome. Patients may present with Cushing syndrome (increased cortisol production, moon face, osteoporosis). Present low sodium, and hypercalcaemia due to production PTH-related peptide. Finger clubbing (between the nail edge and the skin there is normally a defined indentation, early on there is a loss of the nail fold, and can get an expansion around the nail base) is not specific but can show up in patients with lung cancer, and constitutional symptoms (e.g. weight loss).

Question 13

Describe NSCLC: squamous cell carcinoma?

Answer 13

Linked to smoking. Mutations are induced by the carcinogens in the cigarette smoke. Cells undergo dysplasia, inter-localised carcinoma, local invasion, and distal invasion of the tumour. From a pathologic point of view, these arise in the main bronchi and segmental bronchi at the mucosal surface. Irritate the airway, and associated with coughing up blood. Invaded through the bronchial wall into the adjacent lung tissue.

Question 14

Describe adenocarcinoma lung cancer?

Answer 14

Seen in non-smokers, and tend to rise out in the periphery of the lungs. May present with chest pain, pneumonia, effusion or pain or apical lesion with horner’s syndrome. Under the microscope, attempts to form glandular structure: papillary, acinar or more solid. It is an NSCLC.

Question 15

Describe bronchioalveolar carcinoma?

Answer 15

This type of carcinoma is a subtype of adenocarcinoma and arises in the wall of the alveolar. Infrequent and can be single or multiple lesions throughout the lung.

Question 16

Describe Small Cell Lung Cancer?

Answer 16

There is a strong link with smoking. Often associated with paraneoplastic syndromes. Arise in the Hila, central, not out in the periphery. They are rapidly growing, necrosis, and secondary bleeding. Under the microscope, there are masses of small round/spindle shaped cells with high mitotic index (rapidly dividing).

Question 17

What is the most common neoplasm in the lung?

Answer 17

Metastatic disease from colorectal, breast or other sites. Often the patient will have multiple tumours in the lung. Usually, the patient’s primary will be known.

Question 18

Describe tumours of the pleura?

Answer 18

There are tumours that arise off the pleural surface (mesothelial cells) - mesothelioma. These are a consequence of exposure to the carcinogenic asbestos fibres. These tend to be occupational exposures: engineering, plumbing, building industry. Once you start to break up the asbestos, that is when you’ll release the fibres.