Multifocal tumors growing on the reason may be in the following areas:
Increased because of multifocal tumors (a) treatment
With the increased levels of cancer diagnosis, treatment improvements, the survival of cancer patients after treatment prolonged the survival of quality requirements have increased. With the follow-up after treatment, review the integrity of the system have sufficient time and opportunity to observe that the second or third new lesions, the survival of cancer patients ever since a short time with no chance to see the phenomenon to be found. Especially after childhood cancer treatment significantly prolonged survival time, the opportunity to discover more new tumor. Literature that: in some young person or child population, the incidence of second tumors reached 12%, and with future follow-up time, childhood cancer patients who have had access to high incidence of cancer in the age old period, The second occurrence foci detection rate will be higher.
Increased because of multifocal tumors (b) treatment
Radiation therapy, chemotherapy, cancer treatment is an important method, and is widely used in clinical practice, only for certain advanced palliative treatment of patients, but also for some of the earlier preoperative adjuvant therapy . Either radiation therapy or chemotherapy in the treatment of malignant tumors at the same time, another cancer-causing cell mutation, cancer and the inhibitory effect on immune function. Foci in the first after being cured by irradiation of the organization, it can be within 5-30 years (mean 15 years) to grow a new cancer. Li and other follow-up observation of 414 cases of survival after radiotherapy in patients followed for an average of 15 years, that is, 19 patients had a second primary malignancy, 17 cases of which cause disease, are the result of radiation therapy.
Current clinical application of chemical on the anti-cancer drugs, most of the existing or the inhibition of tumor cell killing effect, but also has different levels of carcinogenic and immunosuppressive effects. Experimental results show that the incidence of many malignancies and the body's immune function, and therefore, chemotherapy drugs suppress the immune function itself can promote tumorigenesis, which has been clinically proven and recognized. In recent years, after chemotherapy depending on the application of new reports of common malignant tumors, in particular, to strengthen the treatment effect, choose radiation therapy and combination chemotherapy in patients, but also on the induction of new tumors had synergistic effect. Thus, with the received radiation and chemotherapy increase the number of patients and survival time, the new second, the second number is bound to increase in cancer incidence.
Increased because of multifocal tumors (c) the susceptibility of the individual
Epidemiological data on cancer shows that the occurrence of cancer on quality and individual susceptibility. The same carcinogenic factors acting on the body does not necessarily have a different disease, a malignant cancer in patients with the same, due to individual physiological function and tumor immunity against different speed of tumor development, severity and prognosis is not the same . Patients have occurred since the first foci, itself implies a predisposition for cancer-causing factors in the environment have a certain sensitivity. Therefore, the tumor was cured after the first, if not lifted the original carcinogenic, or cancer-causing factors on the susceptibility of the body has not changed, there is again the possibility of a second tumor. But some people have different understanding of the view that a cancer cure, the body may have reduced the occurrence of other autoimmune and cancer risk. However, clinical statistics show that cancer be cured after the first, the possibility of occurrence of a second malignancy than normal for the common, many scholars agree that a second malignancy, or with the body's susceptibility and bias-related argument. Particular system or related systems in the same place especially in patients with second tumors.
[1] [2] Next