Wednesday, July 11, 2007

Lung Carcinoma

Lung carcinoma is a malignant lung tumor usually categorized as small cell or non–small cell. Cigarette smoking is the major risk factor for most types. Symptoms include cough, chest discomfort, and, less commonly, hemoptysis, but many patients are asymptomatic and some present with metastatic disease. Diagnosis is suspected by chest x-ray or CT scan and confirmed by biopsy. Treatment is with surgery, chemotherapy, and/or radiation therapy. Despite advances in treatment, the prognosis is poor, and attention is focused on early detection and prevention.

Epidemiology, Pathophysiology, and Classification

An estimated 171,900 new cases of lung carcinoma are diagnosed each year in the US, and the disease causes 157,200 deaths annually. The incidence is rising in women and appears to be leveling off in men. Black men are at especially high risk.

Cigarette smoking, including passive (secondhand) smoking, is the most important cause. Risk differs by age and smoking intensity and duration; risk after smoking cessation declines but probably never returns to baseline. Exposure to radon, a breakdown product of naturally occurring radium and uranium, is the most important environmental risk factor in nonsmokers.

Chest Wall Tumors

Primary chest wall tumors consist of 5% of all thoracic tumors and 1 to 2% of all primary tumors. Almost 12 are benign, the most common of which are osteochondroma, chondroma, and fibrous dysplasia. A wide range of malignant chest wall tumors exist. Over 12 are metastases from distant organs or direct invasions from adjacent structures (breast, lung, pleura, mediastinum). The most common malignant primary tumors arising from the chest wall are sarcomas; about 45% originate from soft tissue and 55% from cartilaginous or bony tissue. Chondrosarcomas are the most common primary bone chest wall sarcoma and arise in the anterior tract of ribs and less commonly from the sternum, scapula, or clavicle. Other bony tumors include osteosarcoma and small-cell malignant tumors (Ewing's sarcoma, Askin's tumor). The most common soft-tissue primary malignant tumors are fibrosarcomas (desmoids, neurofibrosarcomas) and malignant fibrous histiocytomas. Other primary tumors include chondroblastomas, osteoblastomas, melanomas, lymphomas, rhabdomyosarcomas, lymphangiosarcomas, multiple myeloma, and plasmacytomas.

Symptoms, Signs, and Diagnosis

Soft-tissue chest wall tumors often present as a localized mass without other symptoms; some patients have fever. Patients usually do not experience pain until the tumor is more advanced. In contrast, primary cartilaginous and bone tumors are often painful.

Patients with chest wall tumors require chest x-ray, CT, and sometimes an MRI to determine the original site and extent of the tumor and whether it is a primary chest wall tumor or a metastasis. Biopsy confirms the diagnosis.

Bronchial Carcinoid

Bronchial carcinoids are rare, slow-growing neuroendocrine tumors arising from bronchial mucosa that affect patients in their 40s to 60s.

Half of patients are asymptomatic, and 1⁄2 present with symptoms of airway obstruction, including dyspnea, wheezing, and cough, which often leads to a misdiagnosis of asthma. Recurrent pneumonia, hemoptysis, and chest pain are also common. Paraneoplastic syndromes, including Cushing's syndrome due to ectopic ACTH, acromegaly due to ectopic growth hormone–releasing factor, and Zollinger-Ellison due to ectopic gastrin production, are more common than carcinoid syndrome (see Carcinoid Tumors: Carcinoid Syndrome), which occurs in < 3% of patients with the tumor. A left-sided heart murmur (mitral stenosis or regurgitation) occurs rarely due to serotonin-induced valvular damage (as opposed to the right-sided valvular lesions of GI carcinoid).

Diagnosis is based on bronchoscopic biopsy, but evaluation often initially involves chest CT, which reveals tumor calcifications in up to 1⁄3 of patients.

Drug Information
scans are useful for determining regional and metastatic spread. Increased urinary serotonin and 5-hydroxyindoleacetic acid levels support the diagnosis but are not commonly present.

Tuesday, July 10, 2007

Airway Tumors

Primary tracheal tumors are rare (0.1/100,000 people). They are often malignant and found at a locally advanced stage. The most common malignant tracheal tumors include adenoid cystic carcinoma, squamous cell carcinoma, carcinoid, and mucoepidermoid carcinomas. The most common benign airway tumor is a squamous papilloma, although pleomorphic adenomas and granular cell and benign cartilaginous tumors also occur.

Symptoms, Signs, and Diagnosis

Patients often present with dyspnea, cough, wheezing, hemoptysis, and stridor. Hemoptysis occurs with squamous cell carcinoma and can lead to earlier diagnosis, whereas wheezing or stridor occurs more often with the adenoid cystic variant. Dysphagia and hoarseness can also be present initially and usually indicate advanced disease.

Symptoms of airway narrowing can herald life-threatening airway obstruction and require immediate hospitalization and evaluation with bronchoscopy. Bronchoscopy can both stabilize the airways and obtain specimens for diagnosis. If a malignancy is found, more extensive testing for metastases is done.

Air Pollution–Related Illness

The major components of air pollution in developed countries are nitrogen dioxide (from combustion of fossil fuels), ozone (from the effect of sunlight on nitrogen dioxide and hydrocarbons), and suspended solid or liquid particles. Burning of biomass fuel is an additional important source of particulate matter indoors in developing countries. Passive smoking can be considered as related.

The effect of air pollution on lung disease can be substantial at high pollution levels, which can trigger asthma and COPD exacerbations. People living in areas with high traffic, especially when stagnant air is created by thermal inversions, are at particular risk. Of the so-called criteria air pollutants (oxides of nitrogen, oxides of sulfur, ozone, carbon monoxide, lead, and particulates), only CO and lead do not affect airways hyperreactivity. Long-term exposure may increase respiratory infections and symptoms in the general population, especially children.

Ozone, which is the major component of smog, is a strong respiratory irritant and oxidant. Levels tend to be highest in the summer, late morning, and early afternoon. Short-term exposures can produce dyspnea, chest pain, and airways reactivity. Children who participate in outdoor sports during high ozone pollution days are more likely to develop asthma. Long-term exposure to ozone produces a small, permanent decrease in lung function.

Dental Health

A bright smile and sweet-smelling breath may be two of the mainstays of Madison Avenue, but the fact remains that healthy teeth and gums can improve your overall well being.

In fact, research studies have recently pointed to gum disease as a trigger to other more serious conditions like diabetes and heart disease.

There was a time when going to the dentist struck fear into the bravest of characters, but today improved techniques have lessened the degree of discomfort felt even in complicated dental procedures.

On the Web, find out more about recent advances in dentistry and cosmetic dentistry, plus how to's on coping with toothache pain, common phobias, and more on self-care, brushing, flossing, and otherwise maintaining good dental habits through a lifetime ...

Alternative Medicine

When East meets West in modern medicine it can often be a source of controversy, but recent studies have been turning up some very persuasive arguments for incorporating non-Western medicine and holistic approaches with more traditional views.

Non-drug treatments are an important part of the debate.

The controversial use of herbs,vitamin and mineral therapies. acupuncture, and chiropracty are now more mainstream than ever as consumers hear more about the sometimes harmful side-effects of traditional drug treatments.

In particular, news about the benefits of Omega-3 fatty acids - proven to treat a host of conditions from ADD to macular degeneration - point to a growing trend toward over-the-counter risk prevention and self-care.

On the Web, keep informed at top sites offering information, results of recent studies, news & updates on the alternative approach to health & fitness ...