JOURNAL
OF SURGICAL
RESEARCH
48, 397-402 (1990)
lmmunohistochemical Demonstration of Human Papilloma Virus Antigen in Human Colon Neoplasms DANIEL KIRGAN, M.D., PACITA MANALO, M.D., AND BYRON MCGREGOR, M.D. Departments
of Surgery and Pathology,
University
Presented at the Annual Meeting of the Association
of Nevada School of Medicine and the VAMC, Rena, Nevada 89502 for Academic Surgery, Louisville,
The presence of human papilloma virus (HPV) has recently been demonstrated in colon tumors, but the incidence of HPV infection in normal colon mucosa or in benign or malignant neoplasms of the mucosa is unknown. We studied both neoplastic and normal human colon tissue for the presence of HPV antigen using immunohistochemical techniques. Ninety colon specimens were studied. Three consecutive series of normal colon mucosa (N = 30), single benign tubulovillous adenomas (N = 30), and invasive carcinomas (N = 30) were selected and confirmed histologically. Formalin-fixed paraffin-embedded samples of each tissue were prepared using immunohistochemical techniques and resultant slides were read blindly and graded simply as positive or negative for HPV antigen. The presence of HPV antigen varied dramatically between groups, with 97% of the invasive carcinomas, 60% of the benign tubulovillous adenomas, and 23% of the normal mucosa positive for HPV antigen. Groups were statistically significant using X2 analysis (P < 0.001). We conclude that an association exists between the human colon neoplasia and the presence of HPV antigen. This may suggest an etiologic role of the virus in 0 1990 Academic Press, Inc. colon cancer.
INTRODUCTION Adenocarcinoma of the colon and rectum is the most prevalent of all gastrointestinal malignancies. Despite an incidence of approximately 125,000 new cases per year and an anticipated mortality of 50% in those cases, therapy following surgical resection has not improved in the last 40 years except for those improvements attributable to perioperative improvements in nutrition, antibiotics, and anesthesia. Detection of early asymptomatic lesions offers the best prognosis; however, efforts at improving screening techniques have had limited success [l] and have been stymied by confusing and contradictory concepts regarding the etiology of colon cancer. While numerous genetic [2, 31, dietary [4, 51, and epidemiological [6, 71 concepts have been promoted, none has completely
Kentucky,
November
15-l&1989
fulfilled an etiologic role. Surprisingly, despite viral associations with neoplasms for over three-quarters of a century, a viral etiology of colon cancer has not been proposed. Evidence is accumulating that supports a causal role for human papilloma virus (HPV) in benign and malignant lesions of the urogenital tract [8, 91 and the head and neck region [lo-131. Identification of this viral association has allowed for changes in diagnostic and therapeutic approaches to these diseases. A similar situation does not exist with colon neoplasms; however, the potential for changes in diagnostic and therapeutic modalities might follow should a viral relationship be demonstrated with colonic neoplasms. We have recently reported HPV antigen by immunohistochemical techniques in benign and malignant neoplasms of the colon [14]. The virus is uniformly distributed in colonic polyps and is probably transmitted hematogenously [ 151. However, the incidence of HPV in normal colon mucosa or malignant tumors of that mucosa are unknown. An ubiquitous presence of the virus in normal colon tissue and colonic neoplasia might well have no clinical relevance. Conversely, if the virus were unique to neoplastic tissue a relationship between the virus and the development of colon cancer would be suggested. To demonstrate the difference between normal colon mucosa and colon carcinoma we compared these tissues using an immunohistochemical technique for the presence of HPV antigen. MATERIALS
AND METHODS
Tissue for study was obtained from the Anatomical Pathology section of the Veterans Administration Medical Center (Reno, NV). Thirty normal colon, 30 single tubulovillous adenomas, and 30 invasive carcinomas were selected and archival paraffin-embedded biopsy specimens were studied. Specimens were regionally distributed and had been previously excised from the rectum (
OF SURGICAL
RESEARCH
48, 397-402 (1990)
lmmunohistochemical Demonstration of Human Papilloma Virus Antigen in Human Colon Neoplasms DANIEL KIRGAN, M.D., PACITA MANALO, M.D., AND BYRON MCGREGOR, M.D. Departments
of Surgery and Pathology,
University
Presented at the Annual Meeting of the Association
of Nevada School of Medicine and the VAMC, Rena, Nevada 89502 for Academic Surgery, Louisville,
The presence of human papilloma virus (HPV) has recently been demonstrated in colon tumors, but the incidence of HPV infection in normal colon mucosa or in benign or malignant neoplasms of the mucosa is unknown. We studied both neoplastic and normal human colon tissue for the presence of HPV antigen using immunohistochemical techniques. Ninety colon specimens were studied. Three consecutive series of normal colon mucosa (N = 30), single benign tubulovillous adenomas (N = 30), and invasive carcinomas (N = 30) were selected and confirmed histologically. Formalin-fixed paraffin-embedded samples of each tissue were prepared using immunohistochemical techniques and resultant slides were read blindly and graded simply as positive or negative for HPV antigen. The presence of HPV antigen varied dramatically between groups, with 97% of the invasive carcinomas, 60% of the benign tubulovillous adenomas, and 23% of the normal mucosa positive for HPV antigen. Groups were statistically significant using X2 analysis (P < 0.001). We conclude that an association exists between the human colon neoplasia and the presence of HPV antigen. This may suggest an etiologic role of the virus in 0 1990 Academic Press, Inc. colon cancer.
INTRODUCTION Adenocarcinoma of the colon and rectum is the most prevalent of all gastrointestinal malignancies. Despite an incidence of approximately 125,000 new cases per year and an anticipated mortality of 50% in those cases, therapy following surgical resection has not improved in the last 40 years except for those improvements attributable to perioperative improvements in nutrition, antibiotics, and anesthesia. Detection of early asymptomatic lesions offers the best prognosis; however, efforts at improving screening techniques have had limited success [l] and have been stymied by confusing and contradictory concepts regarding the etiology of colon cancer. While numerous genetic [2, 31, dietary [4, 51, and epidemiological [6, 71 concepts have been promoted, none has completely
Kentucky,
November
15-l&1989
fulfilled an etiologic role. Surprisingly, despite viral associations with neoplasms for over three-quarters of a century, a viral etiology of colon cancer has not been proposed. Evidence is accumulating that supports a causal role for human papilloma virus (HPV) in benign and malignant lesions of the urogenital tract [8, 91 and the head and neck region [lo-131. Identification of this viral association has allowed for changes in diagnostic and therapeutic approaches to these diseases. A similar situation does not exist with colon neoplasms; however, the potential for changes in diagnostic and therapeutic modalities might follow should a viral relationship be demonstrated with colonic neoplasms. We have recently reported HPV antigen by immunohistochemical techniques in benign and malignant neoplasms of the colon [14]. The virus is uniformly distributed in colonic polyps and is probably transmitted hematogenously [ 151. However, the incidence of HPV in normal colon mucosa or malignant tumors of that mucosa are unknown. An ubiquitous presence of the virus in normal colon tissue and colonic neoplasia might well have no clinical relevance. Conversely, if the virus were unique to neoplastic tissue a relationship between the virus and the development of colon cancer would be suggested. To demonstrate the difference between normal colon mucosa and colon carcinoma we compared these tissues using an immunohistochemical technique for the presence of HPV antigen. MATERIALS
AND METHODS
Tissue for study was obtained from the Anatomical Pathology section of the Veterans Administration Medical Center (Reno, NV). Thirty normal colon, 30 single tubulovillous adenomas, and 30 invasive carcinomas were selected and archival paraffin-embedded biopsy specimens were studied. Specimens were regionally distributed and had been previously excised from the rectum (
