Bronchial carcinoid is a rare tumor, making up 0.5 to 1.0% of all primary lung tumors. There is no known relationship to smoking or other environmental factors. Carcinoid tumors commonly present with hemoptysis, wheezing, stridor, recurrent pneumonia, or lung abscess due to bronchial obstruction. Many patients, however, are asymptomatic and tumor is an incidental radiographic finding. They spread by either the lymphatics or the bloodstream. Prognosis depends on the histologic appearance. Typical (well-differentiated) tumors are usually indolent with survival exceeding 90% after resection. Carcinoids with atypical histologic features (architectural disorganization, necrosis, or a mitotic rate of 2-5 mitoses per 10 high power fields) have a worse prognosis. They are much more likely to recur locally or to have distant metastases.
A 68-year-old male former smoker, originally presented with hemoptysis and was found to have a right middle lobe endobronchial carcinoid. A bronchoscopic biopsy revealed cells with bland nuclei, less than two mitotic figures per high power field, and no areas of necrosis. A right middle lobectomy was performed. Surgical margins and sampled lymph nodes were free of tumor. The patient did well postoperatively but did not follow-up in the pulmonary clinic. Two years later, the patient was seen with a 6 month history of hemoptysis and dyspnea on exertion. He denied any flushing, diarrhea, or abdominal cramping. Physical exam revealed wheezing localized over the right lung field and was otherwise normal. Computed tomography of the chest demonstrated probable endobronchial lesions in the upper trachea and the right mainstem bronchus. Bronchoscopy demonstrated numerous endobronchial lesions in the subglottic space, the upper trachea, and throughout the right mainstem bronchus and bronchus intermedius. Biopsies were obtained from the distal bronchus intermedius and the pathology revealed atypical histologic features with seven mitoses per ten high power fields.
Bronchial carcinoid is usually a slow growing, locally invasive malignant tumor. Chemotherapy and radiation therapy are ineffective treatments; resection is the only means of cure. Many techniques have been shown to be successful: bronchoscopic resection, bronchial sleeve resection, wedge resection, lobectomy, and pneumonectomy. In histologically typical carcinoid with small tumor size and complete resection (like our patient initially), 10-year survival rates are in excess of 95%. Carcinoid tumors generally metastasize to the liver, bones, brain, and adrenal glands. Recurrence after resection is generally local to the area of resection or to regional lymph nodes. Although treatment for endobronchial carcinoid is often successful, they have a highly varied clinical course. Aggressive metastatic disease with survival less than one year has been reported. Our patient was admitted following his bronchoscopy. Further work-up revealed distant metastases to the liver, spleen, and vertebral bodies. Resection of the tracheal tumors using carbon dioxide laser was planned but the patient developed a myocardial infarction. He supsequently expired from respiratory failure deciding against further treatment.
Patients with bronchial carcinoid have a variable course and require regular follow-up evaluation, although whether this will allow earlier detection of recurrence and improve outcomes requires further study.
M.J. Rossing, None.