SYMPTOMATOLOGY.—The interest of the clinical observer nucleates itself around the symptomatology and diagnosis. The frequent negative results of physical examination indubitably prove that its teachings alone are insufficient for the purposes of diagnosis, so that any study of a case would be partial which did not unite the evidence yielded by physical signs with the general symptoms. The clinical evidences are more definite when the neoplasms are multiple and associated with some mediastinal process than when single or absolutely primary growths. The development of the disease is insidious. Gradually the facies and general surface of a patient indicate the true nature of the malady by the characteristic cachexia. Cough is an early symptom, unimportant save that it cannot be assigned to any definite cause. It may be dry and hard, attended only by expectoration of glairy mucus, or the sputa may be purulent. Usually the amount is in ratio with the degree of coexistent bronchitis. In the latter stages of the disease the sputa may contain blood, resembling prune-juice or black-currant jelly, due to erosion of some of the blood-vessels. In this stage of softening cells characteristic of the new growth, with portions of the pulmonary structure, may be found on microscopic examination of the sputa; the appearance of the expectoration sometimes suggests fibrinous bronchitis.
When there is elevation of temperature it may present a hectic type, with night-sweats, which are stated by Walsh to be sometimes confined to the affected side. The presence of an abnormal temperature-curve is indicative of associated inflammation of the bronchial mucous membrane, the development of a pleural process or of phthisis, especially the fibroid form. The pulse becomes accelerated in ratio to the degree of these inflammations and the failure of the sufferer's strength.
The new growth determines some mechanical symptoms cognate to all intra-thoracic tumors, especially those which involve the mediastinum. Lancinating pain would presumably be a constant symptom, but is, in fact, infrequent, unless the growth or growths enlarge so as to cause pressure on the nerve-trunks, in which event pain may become a distressing symptom. Characteristic pains complicate those cases in which the pleural tissues are involved in the morbid process. Dyspnoea is a pressure-symptom of considerable import if other conditions capable of producing it, especially uncomplicated emphysema, are rigidly excluded. When the new formation is infiltrated throughout the lungs, the growth may, as in miliary tubercle, impair the aërating power of the lungs by diminishing their elasticity and increasing their density. When, however, the process is local and restricted, the dyspnoea may be due to irritation of the terminal filaments of the vagus; this being a mixed nerve composed of accelerator and inhibitory filaments, the balance of innervating power may be readily destroyed and partial or incomplete respiratory effort follow. Dyspnoea may also result from pleural adhesions or effusions, or may be secondary to direct cardial or pericardial involvement in the cancerous process. Palpitation or increased pulse-rate may be referred to irritation of the vagi, or to some of the foregoing pathological processes.
Kindred to these symptoms are the changes in the voice, which sometimes undergoes frequent variations due to irritation or pressure on the trachea or on the branches of the pneumogastric nerve, especially when mediastinal disease is present. Aphonia, huskiness, a bass voice, or high treble, one or all, may be constant or alternating harbingers of the concealed mischief. The laryngoscope will inform one whether there is direct involvement of the larynx with morbid growth. Dysphagia is to be expected if the new formation involves the regions through which the oesophagus passes, and a sacculated pouch may be formed above the compressed spot. Changes of posture may increase or diminish the pressure, and thus the dysphagia or dyspnoea may at times be more pronounced than at others. Dysphagia may also be due to swelling of the oesophagus near the location of pressure. Reflex irritation of the sympathetic ganglia may induce pupillary contractions in one or both eyes: this symptom is chiefly present when the mediastinum is involved.
The physical signs contingent on pulmonary cancer include those ordinarily indicative of bronchitis with or without atrophic emphysema, simple pleural effusion, or chronic pleurisy with retraction. By inspection a study should be made of the contour of the thorax, the respiratory movement, and displacements of the intra-thoracic viscera. The thorax may appear enlarged, either from the new formation or from associated pleural effusions. It is often retracted, owing to the atrophic changes, and collapse brought about by the new formation or induced by pleural adhesions. The movements of the chest, unless there is a pleural complication, possess no distinctive character in this disease. Displacements of the heart or trachea may be expected on mechanical principles if there is mediastinal disease. General inspection may detect in the clubbed fingers evidences of venous obstruction, and sometimes an asphyxial hue of the upper portion of the body. Nearly always a general emaciation with anxious expression exists, and a tawny or lemon-hued skin indicative of the cancerous cachexia.
By palpation of the substernal or supra-clavicular spaces one may reach masses of painless, movable, glandular enlargement, but these may be easily overlooked unless a careful study be pursued. Circumscribed swellings of the thoracic walls may be detected, though not often, and the glands of the axillæ and neck may enlarge. Palpation may also reveal an inequality in volume between the radial pulses, but not so commonly as in purely mediastinal tumors or in aneurisms. Percussion and auscultation are negative or yield an area of dulness or flatness with restricted or absent respiratory murmur. When there is a single large growth the boundaries of these signs are local. If the tumors are diffused the respiratory murmur varies. In tiers of lung it is feeble or absent; elsewhere it is harsh, puerile, or bronchial. Chiefly remarkable is the fact that the character of the respiratory murmur cannot be harmonized with any other pulmonary states when the entire clinical evidence is taken. Vocal resonance corresponds with the respiratory murmur according to accepted laws. When there is pressure on the principal bronchus on one or both sides, one can detect either a snoring, increased bronchial respiration, or else, if the pressure decidedly narrows the calibre of the bronchus, the breathing becomes feeble or wheezing. Expiration may be prolonged and sonorous in character, with or without râles. The pressure is rarely equal on the two sides. The vocal resonance in these cases is ringing and brazen. Mensuration corroborates inspection. Pleural effusion from whatever cause is revealed by the ordinary signs. Enlargement of the bronchial glands, either primary or coexistent with the development of cancer in the lung, reveals itself by pressure-symptoms proportionate in their severity to the degree of bronchial enlargement. Pain, laryngeal irritation, differences in the radical pulses, tumor if the enlargement is anterior, one or all, may be present. The aorta itself may be compressed by the enlarged glands; and by the narrowing of its lumen thrill, and even systolic, murmur can appear, making a differential diagnosis from aortic aneurism very difficult. (Vide [MEDIASTINAL TUMORS].) Embolism and thrombosis, with the ordinary symptoms, may complicate the course of pulmonary cancer and obscure the diagnosis.
The duration of cancer of the lung is fixed by Walsh at 13.2 months, mean average, maximum, at 27 months; minimum, at 3.5 months; but this is based on a confessedly small contingent of cases. The first symptoms, dry cough, pain in the chest, difficulty of breathing, may last for some years without alarming the patient. After the more dangerous phenomena appear the course is often more rapid. The history of cancer in the lung in the main corresponds with cases of similar types of cancer elsewhere. The grave symptoms appear earlier in cases of mediastinal cancer than in cancer of the lungs proper. Death may result from asphyxia; from bronchial obstruction; from pulmonary oedema occurring suddenly, as in chronic alcoholism; from embolism of the pulmonary artery; or from pleural effusion. Life may gradually ebb away through general asthenia with malnutrition; in some remarkable cases the same result is accompanied by hectic fever and the typhoid phenomena, with evidences of tissue-disintegration.
COMPLICATIONS.—The complications of pulmonary cancer have been already outlined. They are chiefly the bronchial, pleural, and mediastinal processes. Primary cancer of the lungs possesses a feeble tendency to metastasis.
DIAGNOSIS.—The most valuable assistance is derived from a close study of the personal and hereditary history. Whenever a new growth has been extirpated, the possibility of its reappearance in the lungs should always be remembered. The most disciplined comparative analysis of physical signs may be fruitless. The origin of a primary growth from the roots of the lungs may help to interpret the physical signs, and examination of the sputa should never be omitted. In secondary cancer the history of the case may include the removal or development of morbid growths from other parts of the body. Any pulmonary symptoms in these cases become more suspicious than they would in persons in whom no signs of cancerous diathesis have ever made their appearance. This rule must not be pressed too far, for forms of pleurisy, bronchitis, and pneumonia or phthisis may be the explanation of the symptoms.
In the differential diagnosis it is a matter of universal experience that some form of chronic pleurisy is the most frequent source of doubt to the clinician. It has been said by Wintrich that vocal fremitus in cancer is more often present than absent. If there is much pleural effusion, paracentesis will be helpful in two ways. When the fluid is turbid, highly albuminous, with a large proportion of coagulable fibrin, it is an evidence of its inflammatory origin; but if it is clear and limpid, and upon standing gives but a delicate veil of pseudo-fibrin, it indicates a passive or mechanical cause. If the fluid evacuated should contain any considerable amount of blood, such a peculiarity in association with the other symptoms already indicated is to be regarded as probable evidence of the existence of cancer of the pleura. If the external veins of the thorax are enlarged, they indicate a deep-seated cause of pressure. In malignant disease with retraction there may be less deepening and narrowing of the intercostal spaces on full respiratory movement than is associated with chronic pleurisy: there is usually greater volume and nearness of the respiratory murmur, although this is more noticeable on the left than on the right side, since the liver is present in the latter. The greater severity of the local symptoms and the increase in gravity of the disease must be contrasted with the features of a disease in the decline, as is the case in chronic pleurisy. Walsh considers that "the normal position of shoulder, spine, and scapulæ distinguishes cancer from the results of simple pleurisy." In addition, we have the shorter duration of cancer, which is never over two and a half years, often less. The lemon-hued cachexia is so frequently absent that the inference from general inspection of the features is marred. From fibroid forms of pulmonary disease we have the pressure-signs, giving evidences of mediastinal new formation; also the possible prune-juice expectoration of cancer. The retraction and displacements of the intra-thoracic organs, chiefly the heart, are greater in fibroid disease than in either pleurisy or cancer.