Chapter 085. Neoplasms of the Lung (Part 10) potx

Neoplasms of the Lung Part 10 Staging of Small Cell Lung Cancer Pretreatment staging for patients with SCLC includes the initial general lung cancer evaluation with chest and abdominal

Chapter 085 Neoplasms of the Lung

(Part 10)

Staging of Small Cell Lung Cancer

Pretreatment staging for patients with SCLC includes the initial general lung cancer evaluation with chest and abdominal CT scans (because of the high frequency of hepatic and adrenal involvement) as well as fiberoptic bronchoscopy with washings and biopsies to determine the tumor extent before therapy; brain CT scan (10% of patients have metastases); and radionuclide scans (bone) if symptoms or other findings suggest disease involvement in these areas Bone marrow biopsies and aspirations are rarely performed given the low incidence of isolated bone marrow metastases Chest and abdominal CT scans are very useful

to evaluate and follow tumor response to therapy, and chest CT scans are helpful

in planning chest radiotherapy ports

If signs or symptoms of spinal cord compression or leptomeningitis develop

at any time in lung cancer patients with disease of any histologic type, a spinal CT

scan or MRI scan and examination of the cerebrospinal fluid cytology are performed If malignant cells are detected, radiotherapy to the site of compression and intrathecal chemotherapy (usually with methotrexate) are given In addition, a brain CT or MRI scan is performed to search for brain metastases, which often are associated with spinal cord or leptomeningeal metastases

Resectability and Operability

In patients with NSCLC, the following are major contraindications to curative surgery or radiotherapy alone: extrathoracic metastases; superior vena cava syndrome; vocal cord and, in most cases, phrenic nerve paralysis; malignant pleural effusion; cardiac tamponade; tumor within 2 cm of the carina (not curable

by surgery but potentially curable by radiotherapy); metastasis to the contralateral lung; bilateral endobronchial tumor (potentially curable by radiotherapy); metastasis to the supraclavicular lymph nodes; contralateral mediastinal node metastases (potentially curable by radiotherapy); and involvement of the main pulmonary artery Pleural effusions are generally considered malignant regardless

of whether they are cytology positive, particularly if they are exudative, bloody, and have no other probable etiology Most patients with SCLC have unresectable disease; however, if clinical findings suggest the potential for resection (most common with peripheral lesions), that option should be considered

Physiologic Staging

Patients with lung cancer often have cardiopulmonary and other problems related to chronic obstructive pulmonary disease as well as other medical problems To improve their preoperative condition, correctable problems (e.g., anemia, electrolyte and fluid disorders, infections, and arrhythmias) should be addressed, smoking stopped, and appropriate chest physical therapy instituted Since it is not always possible to predict whether a lobectomy or pneumonectomy will be required until the time of operation, a conservative approach is to restrict resectional surgery to patients who could potentially tolerate a pneumonectomy In addition to nonambulatory performance status, a myocardial infarction within the past 3 months is a contraindication to thoracic surgery because 20% of patients will die of reinfarction An infarction in the past 6 months is a relative contraindication Other major contraindications include uncontrolled major arrhythmias, an FEV1 (forced expiratory volume in 1 s) <1 L, CO2 retention (resting PCO2 >45 mmHg), DLCO <40%, and severe pulmonary hypertension Recommending surgery when the FEV1 is 1.1–2.0 L or <80% predicted requires careful judgment, while an FEV1 >2.5 L or >80% predicted usually permits a pneumonectomy In patients with borderline lung function but a resectable tumor, cardiopulmonary exercise testing could be performed as part of the physiologic evaluation This test allows an estimate of the maximal oxygen consumption (ṼO2max) A ṼO2max <15 mL/kg per min predicts for high risk of postoperative complications

Lung Cancer: Treatment

The overall treatment approach to patients with lung cancer is shown in Table 85-4 Patients should be encouraged to stop smoking, particularly if they will be undergoing surgery or radiation therapy Those who do fare better than those who continue to smoke

Table 85-4 Summary of Treatment Approach to Patients with Lung Cancer

Non-Small Cell Lung Cancer

Stages IA, IB, IIA, IIB, and some IIIA:

Surgical resection for stages IA, IB, IIA, and IIB

Surgical resection with complete-mediastinal lymph node dissection and consideration of neoadjuvant CRx for stage IIIA disease with "minimal N2 involvement" (discovered at thoracotomy or mediastinoscopy)

Consider postoperative RT for patients found to have N2 disease

Stage IB: discussion of risk/benefits of adjuvant CRx; not routinely given

Stage II: Adjuvant CRx

Curative potential RT for "nonoperable" patients

Stage IIIA with selected types of stage T3 tumors:

Tumors with chest wall invasion (T3): en bloc resection of tumor with involved chest wall and consideration of postoperative RT

Superior sulcus (Pancoast's) (T3) tumors: preoperative RT (30–45 Gy) and CRx followed by en bloc resection of involved lung and chest wall with postoperative RT

Proximal airway involvement (<2 cm from carina) without mediastinal nodes: sleeve resection if possible preserving distal normal lung or pneumonectomy

Stages IIIA "advanced, bulky, clinically evident N2 disease" (discovered preoperatively) and IIIB disease that can be included in a tolerable RT port:

Curative potential concurrent RT + CRx if performance status and general medical condition are reasonable; otherwise, sequential CRx followed by RT, or

RT alone

Stage IIIB disease with carinal invasion (T4) but without N2 involvement:

Consider pneumonectomy with tracheal sleeve resection with direct reanastomosis to contralateral mainstem bronchus

Stage IV and more advanced IIIB disease:

RT to symptomatic local sites

CRx for ambulatory patients; consider CRx and bevacizumab for selected patients

Chest tube drainage of large malignant pleural effusions

Consider resection of primary tumor and metastasis for isolated brain or adrenal metastases

Small Cell Lung Cancer

Limited stage (good performance status): combination CRx + concurrent chest RT

Extensive stage (good performance status): combination CRx

Complete tumor responders (all stages): consider prophylactic cranial RT

Poor-performance-status patients (all stages):

Modified-dose combination CRx

Palliative RT

All Patients

RT for brain metastases, spinal cord compression, weight-bearing lytic bony lesions, symptomatic local lesions (nerve paralyses, obstructed airway, hemoptysis, intrathoracic large venous obstruction, in non-small cell lung cancer and in small cell cancer not responding to CRx)

Appropriate diagnosis and treatment of other medical problems and supportive care during CRx

Encouragement to stop smoking

Entrance into clinical trial, if eligible

Abbreviations: CRx, chemotherapy; RT, radiotherapy