472 TUMOES. 



DuHons tumors are those which at the outset exhibit a benign 

 type, but spontaneously, or by improper or incomplete surgical 

 interference, gradually assume the characteristics of malignant 

 tumors 5 or, being from the first in a moderate degree malignant, 

 gradually become infectious, and multiply both locally and in the 

 internal organs. 



The peculiar wasting of the body, the depreciation of the con- 

 stitution, the so-called "dyserasia," or "cachexia," which by 

 former surgeons was considered as the primary cause of the for- 

 mation of malignant tumors, to-day is regarded as of secondary 

 origin. In former times, cancer was considered as the result 

 of a certain dyscrasia; to-day, surgeons are satisfied that tumors 

 of this kind are the results of a local or general disposition. These 

 expressions, as a matter of course, explain nothing. 



(a) Clinical and pathological features. The clinical differences 

 between benign and malignant tumors are not distinctly marked in 

 all cases, but the degree of malignity can usually be determined. 



Pain in benign tumors is only exceptional, and if present it is due to 

 pressure and tension, or a transient inflammation, and not lasting. Fibroma 

 and cavernous angioma are sometimes painful ; neuroma is, as a rule, painful 

 in a high degree. Malignant tumors are from the first painful, or become 

 so in their course ; the more intense the pain the greater, as a general thing, 

 is their malignity. Especially painful are malignant tumors growing in locali- 

 ties which are abundantly supplied with nerves f. i., the socket of the eye, 

 the parotid region, the tongue, etc. 



The boundary in benign tumors is, in most cases, sharply defined to the 

 sight or touch, and the tumor has a certain degree of movability, owing 

 frequently to the presence of an ensheathing capsule. Malignant tumors 

 usually appear as an infiltration, without sharp boundaries separating them 

 from the neighboring tissues. It is only exceptional that a malignant tumor 

 is sharply marked. 



Growth in benign tumors, as a rule, is decidedly slower than in malignant. 

 It takes a number of years for a fibroma to attain the size of a man's fist, while 

 malignant tumors often reach the same size in a few months or years. 

 Scirrhus or hard cancer is an exception ; it arises frequently with an apparent 

 diminution of the bulk of the organ invaded, f. i., the female breast, and 

 during a number of years shows only a limited growth ; while, on the other 

 hand, some benign tumors (for instance, the so-called cysto-sarcoma or myxo- 

 adenoma of the female breast) may increase with great rapidity. 



The integument in benign tumors remains movable and pliable even after 

 the tumor has reached considerable size. It is only after inflammation has 

 been induced by pressure that a fixation of the skin occurs. Malignant 

 tumors, though growing beneath the skin, very soon invade that structure and 

 render it immovable before any considerable distension has taken place. There 

 is an exception to this rule when an aponeurotic or serous layer intervenes 

 between the tumor and the skin. 



