Hemoptysis can occur at any stage of lung cancer, from diagnosis to the terminal care of lung cancer patients. The clinical management of malignancy-associated hemoptysis may additionally be aggravated by systemic anticoagulation therapies or other concomitant pulmonary disease states, such as inflammatory/infectious lung disease or pulmonary vascular abnormalities.1
VASCULAR ANATOMY OF THE LUNGS
The lungs are supported by a dual vascular circulation: the pulmonary circulation (usually a low-pressure system) and the bronchial arteries, small vessels that travel with the bronchial network. The bronchial arteries support the architecture of the lung with a high-flow, high-pressure system. Bleeding from the bronchial arteries can vary from minor hemoptysis to large-volume hemoptysis leading to hypoxemia from drowning. Similar to other causes of hemoptysis, malignancy-associated hemoptysis occurs primarily from the bronchial arteries (82%) and uncommonly from the pulmonary arteries (6.4%).2
Hemoptysis attributable to lung cancer may manifest (1) as a harbinger of lung cancer in 27% of patients as determined by population-based series3,4; (2) as an iatrogenic complication during the investigative phase of cancer; or (3) as a terminal event in the late stages of lung cancer. Hemoptysis has been shown in autopsy series to be the cause of death in up to 12% of patients with lung cancer.5
HEMOPTYSIS AS A HARBINGER OF CANCER
Hemoptysis-associated malignancy varies with the different histologic subtypes of lung cancer; at least 21.6% of patients during their struggles with lung cancer will experience some form of hemoptysis.6 As a presenting symptom, it carries a positive predictive value of greater than 5% with a likelihood ratio of up to 13 for identifying cancer of the lung.7,8 The only other higher likelihood ratio with regard to lung cancer is clubbing of the digits as a physical sign.9 The initial presentation of hemoptysis is so concerning, based on emotive response, it may drive patients toward early investigation because of the fear of cancer.7
A previous large review of lung cancer patients conducted by the Veteran’s Administration in 1980 revealed that the amount of hemoptysis varies in accordance with the different histologic types of lung cancer. Hemoptysis occurs in association with squamous cell cancer (4.2%), adenocarcinoma (15.7%), and small cell carcinoma (16%). With large cell carcinoma it occurs in 23% of cases.4 However, in squamous cell lung cancer, as stage migration increases from early to late stages, there is an increase in the rate of hemoptysis.3 Furthermore, the amount of hemoptysis differs strikingly for each histologic type, with severe hemoptysis occurring primarily in squamous cell cancer (50–88% of severe hemoptysis cases). Adenocarcinoma and large cell carcinoma contribute far fewer cases to series of patients presenting with severe hemoptysis.2,4,5 Malignancy-associated massive hemoptysis is also more commonly seen with tumor necrosis or cavitation (21–50%), ...