Büyük adenomatöz kolorektal poliplerde human papilloma virüs varlığının araştırılması

Öz Kolorektal kanser dünya çapında en sık görülen malignitelerden biridir. Genellikle adenomatöz polip zemini üzerinde gelişir. İnsan papilloma virüsü (HPV), anogenital enfeksiyonlara neden olur ve serviks kanseri ile iyi bilinen bir ilişkiye sahiptir. Bununla birlikte, HPV ve kolorektal polip ve kanser arasındaki ilişkiyi araştıran çalışmalarda çelişkili sonuçlar vardır. Bu nedenle, kanser potansiyeli yüksek olan kolorektal adenomatöz poliplerde HPV varlığını değerlendirdik. Çalışmaya, alt gastrointestinal semptomların taranması veya değerlendirilmesi için total kolonoskopi uygulanan hastadan ≥1 cm boyutundaki polip alındı. Numuneler, real-time PCR kullanılarak 25 genotip için tarandı. Real-time PCR kullanılarak DNA izolasyon analizinde hiçbir örnekte HPV DNA saptanmadı. Sonuç: HPV ile adenomatöz kolorektal polipler arasında bir ilişkinin olamadığına inanıyoruz. Bu konuyu açıklığa kavuşturmak için daha fazla çalışmaya ihtiyaç vardır. Anahtar Kelimeler: Human papilloma virüsü, adenomatöz polipler, kolorektal kanser Yayın Bilgisi


INTRODUCTION
Colorectal cancer (CRC) is one of the most common malignancies worldwide, resulting from adenomatous polyps in most cases.
Adenomatous polyps are benign epithelial tumors with malignant potential and 95% of colon cancers arise from these polyps.However, adenomas have malignant transformation potential by 5%. 1 Colorectal carcinoma risk is increased in adenomatous villous/tubulovillous polyps larger than 1cm. 2 Human papilloma virus (HPV) infects basal epithelial cells such as skin and mucosa.High-risk genotypes of HPV lead Online Türk Sağlık Bilimleri Dergisi 2018, Cilt 3, Sayı 3, 145-154

Araştırma Makalesi
Mehmet Ali ERDOĞAN 146 mainly to cervix cancer as well as other mucosal tumors. 3Given the fact that HPV is associated to anogenital or oropharyngeal cancers, studies have been conducted to investigate relationship between HPV and CRC; however, such a relationship is unclear.Besides studies showing relationship between HPV and CRCs, there are also studies proposing vice versa. 4,5 this study, we investigated whether or not HPV plays role in formation and malignant transformation of adenomatous colorectal polyps that are involved in the development of colorectal cancers.

RESULTS
Overall, 49 patients were included in the study.
Polypectomy sites are shown in (Table 1).
Histopathological examination of samples revealed severe dysplasia in 65.3% (n=32) and mild dysplasia in 34.3% (n=17).Carcinomatous foci were detected in one sample with severe dysplasia.
No significant relationship was detected between involvement site and severity of dysplasia (p=0.42).
In HPV screening, no HPV was detected in obtained samples.No Target DNA could be detected in DNA extracts by real-time PCR analysis (Figure 1a,1b).These results were confirmed by formed amplicons using melt curve analysis (Figure 2a,2b).The included internal control DNA was studied separately and isolation success and no PCR inhibition was observed in samples (Figure 3a,3b).

DISCUSSION
In this study, the presence of HPV in adenomatous colorectal polyps>1cm in size could not be detected.In the studies conducted so far, HPV has been linked to many cancers, mainly anogenital cancers.HPV strains such as HPV 16, 18-31 and 45, considered to be oncogenic, were detected in cervix cancers and anal cancers.
This study was conducted at Endoscopy Unite of Karabuk Teaching Hospital of Karabuk University.The study included patients (aged ≥18 years) who underwent total colonoscopy for evaluation of lower gastrointestinal symptoms or screening.The patients unwilling to participate and those with additional pathology in colon (Crohn's disease, ulcerative colitis etc.) were excluded.All colonoscopy evaluations were performed by an experienced gastroenterologist and polypectomy was performed to all polyps detected during colonoscopy.Polyps with a size of ≥1cm had been accepted as large polyps. 6Of polyps removed, samples taken from those≥1cm in size were placed in plates specially designed for HPV screening and stored at -80 °C.The polyps removed were placed into formaldehyde solution for pathological evaluation.The polyps reported to be adenomatous were included.