Chapter 085. Neoplasms of the Lung (Part 17) docx

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Chapter 085. Neoplasms of the Lung (Part 17) docx

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Chapter 085. Neoplasms of the Lung (Part 17) Chemotherapy The chemotherapy combination most widely used for SCLC is etoposide plus cisplatin or carboplatin, given every 3 weeks on an outpatient basis for four to six cycles. Increased dose intensity of chemotherapy adds toxicity without clear survival benefit. Appropriate supportive care (antiemetics, fluid support with cisplatin, monitoring of blood counts and blood chemistries, monitoring for signs of bleeding or infection, and, as required, use of hematopoietins) and adjustment of chemotherapy doses on the basis of nadir granulocyte counts are essential. The prognosis of patients who relapse is poor. Patients who relapse >3 months since the completion of their initial chemotherapy (so-called chemosensitive disease) have a median survival of 4–5 months; patients who do not respond to initial chemotherapy or relapse within 3 months (chemorefractory disease) have a median survival of only 2–3 months. Patients with chemosensitive disease may be retreated with their initial regimen. Topotecan has modest activity as second-line therapy, or patients can be entered onto clinical trials testing new agents. Considerations for Therapy of SCLC Limited-Stage Disease Combined-Modality Chemoradiotherapy Radiation therapy to the thorax is associated with a small but significant improvement in long-term survival for patients with limited-stage SCLC (5% at 3 years). Chemotherapy given concurrently with thoracic radiation is more effective than sequential chemoradiation but is associated with significantly more esophagitis and hematologic toxicity. In one randomized study, twice-daily hyperfractionated radiation was compared with a once-daily schedule; both were administered concurrently with four cycles of cisplatin and etoposide. Survival was significantly higher with the twice-daily regimen (median survival 23 months compared with 19 months; 5-year survival 26% compared with 16%), but the twice-daily regimen gave more grade 3 esophagitis and pulmonary toxicity. Patients should be carefully selected for concurrent chemoradiation therapy based on good performance status and pulmonary reserve. PCI significantly decreases the development of brain metastases (which occur in about two-thirds of patients who do not receive PCI) and results in a small survival benefit (~5%) in patients who have obtained a complete response to induction chemotherapy. Deficits in cognitive ability following PCI are uncommon and often difficult to sort out from effects of chemotherapy or normal aging. Radiation Therapy for Palliation Palliative radiation therapy is an important component of the management of SCLC patients. Cranial radiation often decreases the signs and symptoms of brain metastases. In the case of symptomatic, progressive lesions in the chest or at other critical sites, if radiotherapy has not yet been given to these areas, it may be administered in full doses (e.g., 40 Gy to the chest tumor mass). Surgery Although surgical resection is not routinely recommended for SCLC, occasional patients meet the usual requirements for resectability (stage I or II disease with negative mediastinal nodes). Often this histologic diagnosis is made in some patients only on review of the resected surgical specimen. However, when such SCLC patients are discovered, they should receive standard SCLC chemotherapy. Retrospective series have reported high cure rates if postoperative chemotherapy is used, although it is unclear what the outcome would be with chemoradiation therapy alone, given the relatively low bulk disease of these patients. Lung Cancer Prevention Deterring children from taking up smoking and helping young adults stop is likely to be the most effective lung cancer prevention. Smoking cessation programs are successful in 5–20% of volunteers; the poor efficacy is due to the addictive nature of nicotine use, which is as strong as addiction to heroin. Chemoprevention is an experimental approach to reduce lung cancer risk; no benefit has yet been shown for chemoprevention. Two putative chemoprevention agents, vitamin E and β-carotene, actually increased the risk of lung cancer in heavy smokers. Benign Lung Neoplasms The benign neoplasms of the lung, representing <5% of all primary tumors, include bronchial adenomas and hamartomas (90% of such lesions) and a group of very uncommon benign neoplasms (epithelial tumors such as bronchial papillomas, fibroepithelial polyps; mesenchymal tumors such as chondromas, fibromas, lipomas, hemangiomas, leiomyomas, pseudolymphomas; tumors of mixed origin such as teratomas; and other diseases such as endometriosis). The diagnostic and primary-treatment approach (surgery) is basically the same for all these neoplasms. They can present as central masses causing airway obstruction, cough, hemoptysis, and pneumonitis. The masses may or may not be visible on radiographs but are usually accessible to fiberoptic bronchoscopy. Alternatively, they can present without symptoms as SPNs and are evaluated accordingly. In all cases, the extent of surgery must be determined at operation, and a conservative procedure with appropriate reconstructions is usually performed. . Chapter 085. Neoplasms of the Lung (Part 17) Chemotherapy The chemotherapy combination most widely used for SCLC is etoposide plus. smokers. Benign Lung Neoplasms The benign neoplasms of the lung, representing <5% of all primary tumors, include bronchial adenomas and hamartomas (90% of such lesions) and a group of very uncommon. Palliative radiation therapy is an important component of the management of SCLC patients. Cranial radiation often decreases the signs and symptoms of brain metastases. In the case of symptomatic,

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