Cancer tumor burden

Generally, a CA 15-3 cutoff of 25 U/ml is used to detect stage I breast cancer. In higher stages, the sensitivity is reported to be much better, which makes it a good test of tumor burden. CA 15-3 is reported to be elevated in other disease conditions such as liver disease (particularly chronic hepatitis, cirrhosis, and carcinoma), some inflammatory conditions (sarcoidosis, tuberculosis, systemic erythematosus), and other carcinoma (lung and ovary). For this reason, positive CA 15-3 results should be interpreted with caution (20,21). 

Kavanagh KT, Hafer LJ, Kim DW, and others. 2001. Green tea extracts decrease carcinogen-induced mammary tumor burden in rats and rate of breast cancer cell proliferation in culture. J Cell Biochem 82(3) 387—398. 

The earliest detectable human cancers usually have a volume of at least 1 cc and contain 10 (1 billion) cells. This number reflects the result of at least 30 cycles of cell division, or cell doublings, and represents a kineti-cally advanced stage in the tumor s growth. Most patients actually have tumor burdens that are greater than 10 . Since the major limiting factor in chemotherapy is cytotoxicity to normal tissues, only a limited log cell kill can be expected with each individual treatment. 

With increasing interest in undertaking animal experimental and human clinical and intervention studies to evaluate the role of lycopene in cancer prevention, it is important that well-established molecular and clinical markers of cancer be used in these studies. In general, the main clinical end points used in animal and human experiments are the tumor burden and volume and survival rates. Now that our understanding of cancer pathology has advanced, several molecular events are beginning to be recognized and used in research to evaluate the outcomes from intervention studies. A brief overview of some of the more important molecular markers of cancer that can and should be used in future studies is presented in this section. 

Singhal, H., Bautista, D.S., Tonkin, K.S., O Malley, F.P., Tuck, A.B., Chambers, A.F., and Harris, J. F. 1997. Elevated plasma osteopontin in metastatic breast cancer associated with increased tumor burden and decreased survival. Clin. Cancer Res. 3, 605-611. 

Anderson, K., Lawson, K. A., Simmons-Menchaca, M., Sun, L., SAnders, B. G., and Kline, K. (2004), a-TEA plus cisplatin reduces human cisplatin-resistant ovarian cancer cell tumor burden and metastasis, Exp. Biol. Med., 229,1169-1176. 

Review of literature suggests that cancer-associated HUS usually occurs during widespread metastatic disease or poorly controlled carcinomas, whereas chemotherapy-associated HUS is more common when the patient is in disease remission or has minimal tumor burden [164,165]. However, the discrimination is not always dear. Murgo [165] attempted to distinguish the characteristics of malignancy-induced and chemotherapy-induced HUS and identified several features to separate the two while Gordon and Kwaan [164] showed that there are more similarities than differences. Some researchers suggest the level of serum... 

In general, the MoAbs used in treating cancer are relatively well tolerated compared with conventional cytotoxic chemotherapy. The main adverse effect associated with rituximab use is infusion-related or hypersensitivity reactions. Patients may experience fever, rigors, dyspnea, hypotension, and rarely anaphylactoid reactions. Premedication with acetaminophen, diphenhydramine, and corticosteroids can reduce these reactions. Patients with significant tumor burden at the time of first treatment with rituximab may experience tumor lysis syndrome, and appropriate measures should be implemented to prevent this complication in these patients. 

W4. Wong, I. H., Yeo, W., Chan, A. T., and Johnson, P. J., Quantitative relationship of the circulating tumor burden assessed by reverse transcription-polymerase chain reaction for cytokeratin 19 mRNA in peripheral blood of colorectal cancer patients with Dukes stage, serum carcinoembryonic antigen level, and tumor progression. Cancer Lett. 162, 65-73 (2001). 

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