Early diagnosis of carcinoma of the lung. Simultaneous screening with chest x-ray and sputum cytology

Early diagnosis of lung cancer

Recent advances in computer-assisted image analysis, tumor biology, PCR-based assays, fluorescence bronchoscopy, spiral CT, endobronchial treatment modalities, and chemoprevention make it possible to re-examine the strategy of early detection in the comprehensive management of lung cancer.

Non-small cell lung cancer. Part I: Biology, diagnosis, and staging

Squamous, large cell, and adenocarcinoma, collectively termed non-small cell lung cancer (NSCLC), are diagnosed in approximately 75% of patients with lung cancer in the United States. The treatment of these three tumor cell types is approached in virtually identical fashion because, in contrast to small cell carcinoma of the lung, NSCLC more frequently presents with localized disease at the time of diagnosis and is thus more often amenable to surgical resection but less frequently responds to chemotherapy and irradiation. Cigarette smoking is etiologically related to the development of NSCLC in the great majority of cases. Genetic mutations in dominant oncogenes such as K-ras, loss of genetic material on chromosomes 3p, 11p, and 17p, and deletions or mutations in tumor suppressor genes such as rb and p53 have been documented in NSCLC tumors and tumor cell lines. NSCLC is diagnosed because of symptoms related to the primary tumor or regional or distant metastases, as an incidental finding on chest radiograph, or rarely because of a paraneoplastic syndrome such as hypercalcemia or hypertrophic pulmonary osteoarthropathy. Screening smokers with periodic chest radiographs and sputum cytologic examination has not been shown to reduce mortality. The diagnosis of NSCLC is usually established by fiberoptic bronchoscopy or percutaneous fine-needle aspiration, by biopsy of a regional or distant metastatic site, or at the time of thoracotomy. Pathologically, NSCLC arises in a setting of bronchial mucosal metaplasia and dysplasia that progressively increase over time. Squamous carcinoma more often presents as a central endobronchial lesion, while large cell and adenocarcinoma have a tendency to arise in the lung periphery and invade the pleura. Once the diagnosis is made, the extent of tumor dissemination is determined. Since most NSCLC patients who survive 5 years or longer have undergone surgical resection of their cancers, the focus of the staging process is to determine whether the patient is a candidate for thoracotomy with curative intent. The dominant prognostic factors in NSCLC are extent of tumor dissemination, ambulatory or performance status, and degree of weight loss. Stages I and II NSCLC, which are confined within the pleural reflection, are managed by surgical resection whenever possible, with approximate 5-year survival of 45% and 25%, respectively. Patients with stage IIIa cancers, in which the primary tumor has extended through the pleura or metastasized to ipsilateral or subcarinal lymph nodes, can occasionally be surgically resected but are often managed with definitive thoracic irradiation and have 5-year survival of approximately 15%.(ABSTRACT TRUNCATED AT 400 WORDS)

Screening by nurse clinicians in cancer prevention and detection

Cancer screening by definition as an organized effort to detect cancer at an early stage when reduced mortality is possible. Cancer screening should not be the exclusive responsibility of comprehensive cancer centers or large urban medical centers. Rather, every health professional should play a significant role in the early detection and education of patients with cancer. As seen here, some of the most common and life-threatening forms of cancer are the most preventable. Practical and inexpensive steps exist for thorough and effective screening. Nurses educated in the early detection of cancer are in a unique position; they are on the front line of patient care in the promotion and education of patients to the many benefits of early detection. Preventive efforts, such as screening and early detection, coupled with vastly improved treatment modalities, provide a very real and potent weapon against diseases that only 20 years ago were considered incurable.

Cytologic diagnosis of radiographically occult squamous call carcinoma of the lung

From 1978-1980, 20 patients with radiographically occult squamous cell carcinoma of the lung were admitted to Toronto General Hospital. Among them, five had in situ carcinoma, three had microinvasive carcinoma, and 12 early invasive. All cases were first diagnosed by cytologic examinations of sputum, localized by bronchoscopy, and had been verified histologically. It appears that a cytologic diagnosis of in situ squamous cell carcinoma of the lung could not be established on the basis of a single abnormal squamous cell or an occasional group of abnormal cells, but could be reached by putting together all the cytologic findings observed in the preparations. The criteria for the cytologic diagnosis are elucidated. Cytomorphologically there was no difference between microinvasive and advanced invasive carcinoma. However, in a patient with known localized in situ carcinoma and previous persistent cytologic findings of the same from that particular site, the finding of frankly malignant cells from the same site in the follow-up bronchoscopic examination was almost definitely an indication of microinvasive carcinoma, which usually showed evidence of both in situ and invasive carcinoma in the bronchial brushing specimens. None of the three microinvasive carcinoma cases had positive lymph nodes, but four of the 12 patients with early invasive carcinoma had metastases to the nodes at the time of surgery. Hence, the best time to effectively treat the invasive squamous cell carcinoma of the lung is at the microinvasive stage when the disease is considered curable.

Lung cancer

Only patients with localized lung cancer benefit from curative resection. Curative radiotherapy is recommended in patients with a resectable tumor in whom surgery is precluded for medical reasons. Adjuvant preoperative or postoperative therapy of any type does not improve the results of surgery except in patients with Pancoast tumor. Therapy for nonlocalized tumors does not affect survival. Radiotherapy has a palliative effect in 50 to 75 per cent of patients presenting with symptoms from either a primary lesion or metastases and should therefore be recommended in symptomatic patients. The palliative effect of chemotherapy is limited in lung cancers other than small cell carcinomas. However, chemotherapy alone or in association with radiotherapy produces remarkable tumor regression and some improvement of survival in small cell carcinoma. The use of immunotherapy in the treatment of lung cancer is still under evaluation.

Preliminary report of the lung cancer detection program in New York

The early lung cancer detection program in New York is described, and preliminary prevalence rate data are reported. Cigarette-smoking men over the age of 45, who are considered at high risk, are encouraged to enroll in the program and, to date, 6,612 have done so. These men receive PA and lateral chest x-rays annually, while a randomly selected sub-population of about half also have sputum cytology every four months. A controlled study of sputum cytology as an adjunct to the chest x-ray is now in progress. There were 15 cases of late lung cancer (pathologic stages II and III) detected at the initial examination, and 11 early cases (pathologic stages O and I). In the population of 3,387 men who had x-rays alone there were three early lung cancers detected; in the population of 3,225 men who had both examinations four early cancers were detected by x-ray and four by cytology. In addition, three cases of larynx cancer were detected by cytology. The early lung cancers detected by x-ray were peripheral and most were bronchiolar or adenocarcinoma; the early cancers detected by cytology were central epidermoid carcinoma of major bronchi. No early carcinomas were detected by both techniques. These findings suggest that a combination of chest x-rays and sputum cytology can be more effective than either one alone in detecting early lung cancer.

Diagnostic and therapeutic challenges following the cytologic diagnosis of in situ carcinoma of the lung

Clinical challenges associated with the cytologic detection of eight cases of occult pulmonary carcinoma are presented. The pulmonary lesions were successfully localized and resected in three of six cases encountered since the availability of flexible fiberoptic bronchoscopy and selective bronchial brushing. Two of the resected neoplasms were unequivocally in situ, while preoperative radiotherapy precluded accurate pathologic determination of invasiveness in the third. The reported experience with unequivocal in situ bronchogenic carcinoma localized and treated surgically prior to invasion through the basement membrane now totals 17 cases (15 previously reported). Forty-four additional cases (43 previously reported) have been localized and resected following early invasion. From this group totaling 61 occult carcinomas, only two patients (3 percent) are known to have died of pulmonary carcinoma during a followup ranging from 2 to 20 years.

The Mayo Lung Project for early detection and localization of bronchogenic carcinoma: a status report

The Mayo Lung Project (MLP) is a screening program designed to detect bronchogenic carcinoma at a curable stage. Screening tests include chest roentgenograms, three-day "pooled" sputum cytology studies, and lung-health questionnaires. These are being applied every four months to a study population of outpatients who have a high probability of developing lung cancer. Initial patient acceptance of the screening program has been excellent. Small asymptomatic lung cancers have been detected both roentgenographically and cytologically. The two procedures have complemented each other with little overlap. Chest roentgenography has proved most useful in diagnosing peripherally situated cancers, whereas sputum cytology studies have been most effective in identifying early squamous cancer involving major airways. At present, more cancers have been detected roentgenographically than cytologically, but the cytologically detected cases appear to have a better prognosis. Roentgenographically occult cancers have been localized with regularity, although the localization process is complicated. Theoretically, vigorous application of radiologic and cytologic screening, combined with optimum use of localizing procedures and treatment, could increase the five-year survival rate among lung cancer patients to nearly 50 percent. However, the actual survivorship attained will ultimately be determined by currently imponderable factors such as patient acceptance of longterm screening, frequency of multicentric respiratory cancers, and incidence of noncancerous smoking-related diseases, especially chronic obstructive pulmonary disease and ischemic heart disease.

Symptoms and Survival in Lung Cancer

From the analysis of 167 patients with lung cancer operated by radical resection at the National Cancer Institute of Milan and from the review of the literature, the authors reach the following conclusions: a) Prognosis of lung cancer is related to symptoms. Prognosis is better in asymptomatic patients and in those with long-term primary symptoms than in patients with short-term symptoms, or with clinical signs of mediastinal involvement or metastases. Symptomatologic classification is therefore useful also in a pretherapeutic phase. b) Although in asymptomatic patients there are better chances of cure, mass screening in asymptomatic people may be unsuccessful because of the limited number of asymptomatic cancers and the limits in radiographic diagnosis. This latter, in fact, even if rouled out in a preclinical phase, is not early. c) We need new epidemiological trends to improve both the effectiveness of mass screening and therapy in asymptomatic people.

The early diagnosis of lung cancer

Earlier diagnosis of malignant disease in the lung may bring about improvements in the treatment. This article discusses the effects of early diagnosis on the prognosis. Cancer of the lung may be associated with other lung pathology, thus increasing the problems of diagnosis. Diagnosis depends on radiological examination, cytology of the sputum, radio-isotope lung scanning and mediastinoscopy: an account is given of how these may be used to diagnose the condition whilst it is still at an early stage and suitable for radical treatment.