Experience with the cytologic detection, localization, and treatment of radiographically undemonstrable bronchial carcinoma

Superficial endobronchial lung cancer: radiologic-pathologic correlation

OBJECTIVE

To analyze the plain chest radiographic and CT findings of superficial endobronchial lung cancer and to correlate these with the findings of histopathology.

MATERIALS AND METHODS

This study involved 19 consecutive patients with pathologically proven lung cancer confined to the bronchial wall. Chest radiographs and CT scans were reviewed for the presence of parenchymal abnormalities, endobronchial nodules, bronchial obstruction, and bronchial wall thickening and stenosis. The CT and histopathologic findings were compared.

RESULTS

Sixteen of the 19 patients had abnormal chest radiographic findings, while in 15 (79%), CT revealed bronchial abnormalities: an endobronchial nodule in seven, bronchial obstruction in five, and bronchial wall thickening and stenosis in three. Histopathologically, the lesions appeared as endobronchial nodules in 11 patients, irregular thickening of the bronchial wall in six, elevated mucosa in one, and carcinoma in situ in one.

CONCLUSION

CT helps detect superficial endobronchial lung cancer in 79% of these patients, though there is some disagreement between the CT findings and the pathologic pattern of bronchial lesions. Although nonspecific, findings of bronchial obstruction or bronchial wall thickening and stenosis should not be overlooked, and if clinically necessary, bronchoscopy should be performed.

Roentgenographically occult small-cell lung cancer: case report and review of the literature

This report describes a rare case of roentgenographically occult small-cell lung cancer in a 73-year-old man with hemoptysis. Fiberoptic bronchoscopy disclosed a 5-mm dome-shaped lesion; a biopsy established the diagnosis of small-cell lung cancer. The patient received a combination of chemotherapy and radiotherapy. More than 10 years later, he is still alive without recurrent disease. A review of the literature of roentgenographically occult small-cell lung cancer revealed the following: (1) a history of heavy smoking was common; (2) double primary bronchogenic carcinoma was noted; (3) hemoptysis or bloody sputum was an initial common symptom; (4) the sensitivity of sputum cytologic analysis was relatively low; (5) the tumor, which was shiny, smooth, and covered with bronchial epithelium, was often located at the bifurcation; and (6) lymph node metastatic involvement occurred.

Endoscopic criteria of early squamous cell carcinoma of the bronchus

BACKGROUND

Early lung cancer, not extending beyond the bronchial cartilaginous layer without regional lymph node involvement is considered curable by endoscopic laser therapy or limited surgery. The endoscopic criteria for early squamous cell carcinoma of the bronchus, however, have not yet been determined.

METHODS

For 44 resected lesions of roentgenographically occult bronchogenic squamous cell carcinomas, the relationship between endoscopic findings and the degree of histologic extent of tumor was examined.

RESULTS

The lesions were divided into three types: polypoid or nodular (PN), flatly spreading (FS), and mixed. Thirty-three lesions arising from the central bronchus included 7, 19, and 7 of the PN, FS, and mixed types, respectively. In the central lesions, the degree of transmural invasion and the greatest dimension correlated, but the degree of intramural invasion of PN-type lesions was higher than that of the FS type. The PN-type lesions smaller than 10 mm and the FS type smaller than 15 mm in greatest dimension were found within the cartilaginous layer without regional lymph node involvement. All lesions of the mixed type were larger than 20 mm. Three of the lesions larger than 20 mm had regional lymph node involvement. All 11 lesions originating in the peripheral bronchus were of the FS type, and a lesion of only 5 mm in greatest dimension had extracartilaginous invasion.

CONCLUSIONS

The endoscopic criteria of early squamous cell carcinoma of the bronchus may be applied to central PN lesions smaller than 10 mm and central FS lesions less than 15 mm in greatest dimension. Any lesions of mixed type should be excluded from the criteria.

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.

Asbestos and cancer in Finland

Cancer mortality of men with diagnosed asbestosis was studied in Finland. Of the 174 men registered as having asbestosis, 56 had died before 1977, whereas the number of expected deaths based on the Finnish male population was only 23.4. The respective figures for lung cancer were 19 observed and 2.1 expected. The mean age of these 19 lung cancer patients was 57.8 yr, and lung cancer was the cause of death (underlying cause) in 35% of all diseased men with asbestosis. The proportion of lung cancer mortality from all deaths among Finnish men 55-64 yr old is 10.8%, which is clearly lower than that among the men with asbestosis. No excess of other malignancies was found in Finland among workers with asbestosis.

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.

Relationships of morphology to clinical presentation in ten cases of early squamous cell carcinoma of the lung

The morphologic changes in 10 patients who were found to have squamous cell carcinoma of the lung before they became evident on chest x ray are discussed. It is suggested that these cases have a long preclinical course as invasive carcinomas that ranges from a microscopic focus of microinvasion (possibly originating from in situ carcinoma in submucosal gland epithelium) to a large concentric carcinoma which may have metastasized to regional lymph nodes. Although the duration of the in situ phase of squamous cell carcinoma of the bronchus in not known, it was evident that the expanse of in situ carcinoma frequently far exceeded that of the invasive carcinoma, and usually extended proximal to the invasive lesion. It is important that the extent of the in situ lesion is determined preoperatively. Finally, multifocal in situ (or invasive) carcinoma was found in at least two of the cases, either synchronously or metachronously.

New horizons in lung cancer diagnosis

Lung cancer is rarely diagnosed and treated while still localized. Sputum cytology allows detection of radiologically occult tumors but conventional endoscopic procedures frequently prove inadequate for localization. It is the purpose of this report to outline the endoscopic observations and methods we have developed in successfully localizing 17 consecutive, radiologically occult carcinomas discovered in the sputum of 15 patients. A detailed examination of the upper respiratory tract demonstrated occult tumors in two patients. A segment by segment fiberbronchoscopic study under anesthesia allows multiple brushings and meticulous handling of specimens. Lesion localization is provided as well as identification of synchronous second primary tumors. Biopsies at the lobar spur and carina assist in determining the proximal extent of carcinoma in situ at potential surgical margins. Newer methods should enhance our recognition of inapparent carcinoma in situ allowing more efficient and more accurate tumor localization and a better appreciation of its extent.

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.

Flexible fiberoptic bronchoscopy. Its place in the search for lung cancer

The use of sputum cytology has demonstrated that conventional bronchoscopic equipment often fails to permit localization of earlier, more peripheral tumors. The flexible fiberbronchoscope now opens up new bronchial horizons but does not replace rigid instruments. Our experience in 300 fiberoptic studies has suggested certain guidelines for determining in which patients the flexible equipment should be used and in which conventional instruments are preferred. By means of a comprehensive endoscopic study, we successfully localized eight “sputum positive,” radiologically occult bronchogenic carcinomas. The fiberbronchoscope is essential in searching the segments for subtle changes of early cancer. These findings are documented by a color television system. A detailed pathological study demonstrates the importance of preoperative marginal biopsies in excluding carcinoma in situ which may extend some distance from even small tumors. In 94 patients with cancer we located 85 (90%) by direct visualization and/or bronchoscopic specimens. Sixty-eight (72%) involved primarily the segmental or more peripheral areas while main bronchus tumors were large and suggested spread from a more distal site of origin. The fiberbronchoscope has greatly extended our capabilities, allowing a better understanding of early lung cancer and greatly improved localization.

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.

Carcinoma in situ and early invasive carcinoma of the bronchus

Ten patients are described who underwent lobectomy or pneumonectomy and were shown to have a bronchial carcinoma in situ or early invasive carcinoma. The diagnosis was generally made only by histological examination following resection. The lesions were all squamous in type. It is probably uncommon for such lesions to be multifocal at any one time and following removal they carry a good prognosis. However, we think that these patients have a much increased chance of subsequently developing further squamous bronchial carcinomas in the remaining lung tissue, and so a prolonged follow-up over many years is desirable. In our series, these early lesions were present in only 2·0% of all resections for lung cancer. A group of patients with such early tumours present with disproportionately severe radiographic changes, as there is a papillary lesion producing bronchial obstruction, and so the lesion appears clinically to be more advanced than it really is. A pre-operative diagnosis of carcinoma in situ is more likely in the other group of patients without obstruction, who are heavy smokers, are chronic bronchitics, and are having repeated small haemoptyses. This group presents a problem in management and requires careful observation. Investigations for finding early lesions include regular cytological examination of the sputum, followed by bronchoscopy in an attempt to localize the lesion if cytology is positive. Lobectomy or pneumonectomy should be undertaken when the site is established.