抄録
Inverted papilloma (IP) in the paranasal sinus is a benign neoplasm with unique clinical characteristics; in particular, a high recurrence rate and concomitant malignant lesions. Because the clinical features of IP sometimes resemble unilateral paranasal sinusitis with polyps, the pre-operative diagnosis of IP is important for complete surgical resection. In this article, we postulate that measurement of serum squamous cell carcinoma antigen (SCCA) and detection of human papillomavirus (HPV) are very important for the diagnosis and treatment of IP.
SCCA, consisting of SCCA1 and SCCA2, was originally isolated biochemically from uterine squamous cell carcinoma (SCC) tissue and is one of the tumor markers for head and neck SCC. A statistically significant elevation of serum SCCA was observed in IP, compared to those with maxillary SCC and inflammatory nasal disease. Moreover, serum SCCA measurement is an effective tool to diagnose not only untreated IP but also recurrent IP. If a high SCCA level remains after surgery, surgeons should pay attention to the possibility of residual or subsequent recurrent lesions. The mRNA expression of SCCA1 and SCCA2 in IP was higher than in maxillary SCC and inflammatory disease. The SCCA2/SCCA1 ratio in IP was similar to that in inflammatory disease, although the ratio in maxillary SCC was significantly higher than in IP and inflammatory disease. Thus, the SCCA2/SCCA1 ratio is useful for detecting SCC among other sinonasal diseases.
There have been several reports regarding the close relationship between IP and human papillomavirus (HPV) infection. Using an auto-nested polymerase chain reaction, the presence of the HPV genome was detected in 46.2%, 27.3% and 7.7% of patients in IP, SCC, and inflammatory diseases, respectively. IP showed significantly higher HPV-positive rates than the inflammatory disease. All types of HPV detected were high-risk HPV, especially HPV-16. One patient with IP and concomitant squamous cell carcinoma showed a high viral load and integration. HPV infection may be involved in the pathogenesis of IP, and a high viral load and integration of HPV have an important role in malignant lesion in association with IP. Further study is needed to clarify whether HPV plays an important role in recurrence or dissemination of IP.
Since many surgical procedures and instruments have been newly developed for endoscopic sinus surgery, endoscopic resection of IP is becoming popular as the optimal treatment for IP. Further development in this field brings both less invasive treatment and lower recurrence rates to patients with sinonasal tumors.
