Lung carcer

 

Lung cancers may be classified according to histological subtypes. The main distinction is between small cell and non- small cell lung cancer. Non-small cell lung cancer is the most common variant and accounts for 80% of all lung cancers.

Non-small cell lung cancer

These share common features of prognosis and management. Paraneoplastic features and early disease dissemination are less likely than with small cell lung carcinoma. They comprise the following tumours:

• Adenocarcinoma (40% cases) most common lung

cancer type encountered in never smokers.

• Squamous cell carcinoma (25% cases) more slow

growing and are typically centrally located

• Large cell carcinoma (10% cases)

Small cell lung carcinoma

Small cell lung carcinomas are comprised of cells with a neuro endocrine differentiation. The neuroendocrine hormones may be released from these cells with a wide range of paraneoplastic associations. These tumours are strongly associated with smoking and will typically arise in the larger airways. They disseminate early in the course of the disease and although they are usually chemosensitive this seldom results in long lasting remissions.

Management of non small cell carcinoma:

Management

• Only 20% suitable for surgery

• Mediastinoscopy performed prior to surgery as CT does not always show mediastinal lymph node involvement

• Curative or palliative radiotherapy

• Poor response to chemotherapy

Surgery contraindications

• Assess general health

• Stage IIIb or IV (i.e. metastases present)

• FEV1 < 1.5 litres is considered a general cut-off point*

• Malignant pleural effusion

• Tumour near hilum

• Vocal cord paralysis

• SVC obstruction