Pain.—Mild renal colic may arise from transient impaction of a clot in the ureter, and a guide to the kidney affected is at once estab lished; but the pain ceases directly the clot is expelled into the blad der, and the shape and appearance of the coagulum in the urine inter pret the cause and character of the renal suffering. When the clots in the bladder are large there may be some difficulty and straining in evacuating them; nay, there may be even temporary retention, but when the clots are evacuated the vesical colic subsides. With these exceptions and that of the hematuria, renal carcinoma is usually a symptomless affection at first. Of those patients who have been under my care not one had pain beyond a slight backache and feeling of lassitude, due to the excessive loss of blood for the first nine months. Pain in the back was, however, induced as the growth progressively increased and involved the surrounding structures. The hemorrhage, probably by depleting the vessels and relieving tension, usually lessens the pain in the later stages.
Pain is, however, experienced if swelling from nephritis ensues. In two cases not included in the above I have known great pain pro duced by septic inflammation of the carcinomatous kidney. In both
eases I believe that the acute suppurative nephritis was the result of catheterism, and death occurred in the very earliest stage (compare section on Treatment).
Tumor. —Probably the very large renal tumors are sarcomatous. The true carcinomata rarely reach a large size without causing much pain and constitutional effects.
Yaricocele occasionally appears in the later stages of renal cancer, and is a very important additional evidence of impediment by pres sure of a malignant growth ; so much so that if a varicocele suddenly makes its appearance in a patient about the age of fifty it impera tively calls for an immediate examination of the kidney of the corre sponding side.
Frequency of micturition apart from that temporarily induced by clot retention * is not common. Obstinate constipation, flatulence, and other digestive troubles are often complained of.
Malaise and cachexia are noticed in rare instances even before the hrematuria or tumor, and are to be regarded as an ominous sign of dissemination. Usually the cachexia is due to loss of blood in the earlier stages.