Large cell carcinoma Accounts for 5-10% of all lung cancers. Strongly associated with cigarette smoking. The lesion occurs peripherally and grows rapidly, with early metastases and a poor outcome They lack any diagnosic features to suggest their diagnosis prior to biopsy.

Pancoast tumors Represent 1-3% of all lung cancers . Typically involve the lower trunks of the brachial plexus, intercostal nerves, stellate ganglion, adjacent ribs, and vertebrae. More than 95% are NSCC . Horner's syndrome, mediastinal and supraclavicular adenopathy and vertebral body invasion portends a poorer prognosis

Pancoast Tumours Imaging MRI is more accurate in identification of the extent of tumor involvement; it is superior to CT scanning in the detection of invasion of adjacent organs (eg, vertebral bodies, brachial plexus, subclavian vessels). CT or MRI of the brain is recommended in the initial evaluation, because distant metastases to the brain are not infrequent

Differential Diagnosis of an opacity at the Superior Sulcus Mesothelioma. Lymphoma. Plasmacytoma. Metastatic malignancies (thyroid, larynx). Lymphomatoid granulomatosis. Cervical rib syndrome. Tuberculosis. Fungal infections.

Small Cell Lung Cancer strong association with smoking . Rapid growth. Early spread to distant sites. Exquisite sensitivity to chemo and radiotherapy. Frequent association with distinct paraneoplastic syndromes. Surgery usually plays no role in its management, except in rare situations (<5% of patients) in which it presents at a very early stage as a solitary pulmonary nodule

Small cell lung cancer 18% of all lung cancers. Often present with bulky hila and mediastinal lymph node masses. TNM system does not provide important prognostic information; only useful in <5%.

Staging of Small Cell Carcinoma Stage Description Limited stage Disease confined to one hemithorax; includes involvement of mediastinal, contralateral hilar, and/or supraclavicular and scalene lymph nodes. Extensive stage Disease has spread beyond the definition of limited stage, or malignant pleural effusion is present

With central tumors, distinguishing primary tumor from lymph node metastasis may be impossible

International Staging System for Lung Cancer This is the common evaluation framework,because, patient treatment options and prognosis are directly related to their tumor stage at presentation . Derived from a TNM classification scheme with four separate stage groups from I to IV. Stage I reflects the best prognosis, stage IV the worst.

Tumor (T) TX - Positive malignant cytology, no lesion seen T1 - Diameter smaller than or equal to 3 cm T2 - Diameter larger than 3 cm T3 - Extension to pleura, chest wall, diaphragm, pericardium, within 2 cm of carina, or total atelectasis T4 - Invasion of mediastinal organs (eg, esophagus, trachea, great vessels, heart), malignant pleural effusion, or satellite nodules within the primary lobe

T1 Tumor Diameter of 3 cm or smaller , surrounded by lung or visceral pleura.

T2: A tumor with any of the following features: Larger than 3 cm. Associated with atelectasis or post-obstructive pneumonitis that does not involve the entire lung . Invades the visceral pleura.

T3: A tumor of any size that directly invades any of the following: The chest wall (including superior sulcus tumors), diaphragm, mediastinal pleura, parietal pericardium.

T3: A tumor of any size that directly invades any of the following Tumor in the main bronchus less than 2 cm distal to the carina (but without involvement of the carina). Tumor associated with atelectasis or obstructive pneumonitis of the entire lung.