Evolution of complement-fixing antibody titers with the development of Burkitt's lymphoma

Histopathology of nasopharyngeal carcinoma: correlations with epidemiology, survival rates and other biological characteristics

A total of 363 cases of nasopharyngeal carcinoma (NPC) in Singapore were classified into squamous cell carcinoma (SCC; 73 cases), non-keratinizing carcinoma (NKC; 178 cases) and undifferentiated carcinoma (UC; 172 cases). Possible biological differences between these histologic types and between tumors with and without lymphocytic infiltration were investigated by correlations with survival rates and with selected epidemiologic, immunovirologic, and immunogenetic data on the disease. The 5-year survival rates following radiotherapy were 25.3% for all cases and 58.8% for tumors restricted to the nasopharynx. The 5-year survival rate for SCC was poorer than for the combined NKC and UC groups (p less than 0.05). The 3-year survival rate was better for tumors with lymphocytic infiltration (p less than 0.05), but there were no differences in the 5-year survivals. The survival rates were better in females (p less than 0.01) and in the younger age groups (p less than 0.01). There were no significant correlations between histopathology of NPC and the distributions of cases by age, sex, HLA antigen profiles, or cell-mediated immune status. Squamous cell carcinoma was associated with lower levels of antibodies to the Epstein-Barr nuclear antigen (p less than 0.05), but there were no differences with respect to antibodies against other EBV related antigens. These findings support the view that SCC, NKC, and UC of the nasopharynx, as defined in the WHO classification, are variants of a fairly homogeneous group of neoplasms in the Singapore population.

Epidemiological evidence for causal relationship between Epstein-Barr virus and Burkitt's lymphoma from Ugandan prospective study

Results from a prospective sero-epidemiological study initiated in Uganda in 1971 indicate that children with high antibody titres to Epstein-Barr virus structural antigens are at high risk of developing Burkitt's lymphoma. These findings strongly support a causal relationship between the Epstein-Barr virus and Burkitt's lymphoma but suggest that the oncogenic potential of the virus is realised only in exceptional circumstances.

Immunity to antigens associated with a cell line derived from nasopharyngeal cancer (NPC) in non-Chinese NPC patients

Delayed hypersensibility to antigens derived from four lymphoid cell lines was measured in 27 non-Chinese patients with nasopharyngeal cancer (NPC) and 63 non-NPC cancer patients. Of the NPC patients, 17/27 (63%) had a positive skin test response to antigens derived from HKLY-28, a lymphoid cell line which was developed from an NPC biopsy. Only 10/51 (20%) and 1/13 (8%) patients with solid tumors and hematopoietic malignancies, respectively, had positive skin test responses to HKLY-28. Positive skin tests were found less frequently when extracts from cell lines derived from normal individuals or lymphoma patients were utilized, although NPC patients were more reactive to two of the non-NPC derived cell lines than the controls. The NPC patients in this study also had significantly elevated antibody titers to the Epstein-Barr virus (EBV), capsid antigen (VCA) and early antigen (EA). Titers were highest in the patients with more anaplastic nasopharyngeal carcinomas. The skin test and serologic data are consistent with studies in Chinese patients, indicating that NPC in non-Chinese and Chinese patients is biologically similar.

Nasopharyngeal carcinoma. IX. Antibodies to EBNA and correlation with response to other ebv antigens in chinese patients

Ninety-five sera from Chinese NPC patients in different stages of the disease, 38 sera from Chinese patients with other cancers, and 50 normal Chinese sera, were titrated for EBNA, VCA, EA and complement-fixing (CF/S) EBV-specific antibodies. The geometric mean (GMT) EBNA antibody titre of patients with NPC at stage I was found to be four times higher than that of normal individuals and increased in parallel with clinical deterioration. Antibody titres against EBNA did not correlate with either VCA or EA antibodies but, in general, correlated with CF/S antibodies. EA antibodies correlated relatively well with VCA antibodies and discriminated better than EBNA titre between NPC at stage I and controls.