Abstract 237P
Background
Gastrointestinal (GI) verrucous carcinoma is an extraordinary rare subtype of squamous cell carcinoma with only 50 cases reported in the literature. Studies that mentioned GI verrucous carcinoma are limited to few case reports. It has a progressive course and grows as a cauliflower-like mass. Thus, surgery is the treatment modality of choice. Due to the very limited data about GI verrucous carcinoma, we aimed to analyze the recent trends and the risk of second primary malignancies (SPM) following primary GI verrucous carcinoma to provide an updated evidence to the literature and help understanding the nature of this rare subtype.
Methods
We used a national cancer database to extract the data of patients diagnosed with GI verrucous carcinoma from 2000-2020. According to the ICD-O-3 WHO classification, we selected the digestive system, oropharynx and hypopharynx. We used a rate session for trend analysis and MP-SIR session to calculate the Standardized Incidence Ration (SIR) as Observed/Expected (O/E) with 95% Confidence Interval (CI) and significant P-value if >0.05.
Results
GI verrucous carcinoma had a PC of -54.1 and an APC of -3.1 (P>0.05). Males had a PC of -48.4 and an APC of -2.8 (P>0.05) while females had a decreased incidence rate compared to males (RR=0.3, PC= -65.5, APC= -5.0, P>0.05). Caucasians had a PC of -53.8 (APC= -18.8, P>0.05) and African-Americans had a PC of -73.8 (APC= -1.2, P>0.05). Out of 267 pateints with GI verrucous carcinoma, 35 developed SPMs in all sites with an O/E of 2.05 (95% CI: 1.43-2.85, P>0.05, ER=118.29). We observed 11 patients developed GI SPMs (O/E= 3.39, 95% CI: 1.69- 6.07, P>0.05, ER= 51.12), eight of them were colorectal SPMs (O/E= 5.02, 95% CI: 2.17- 9.89, P>0.05, ER= 42.22).
Conclusions
The results of this study showed promising decreased trends for GI verrucous carcinoma along the past two decades with more decreased incidence in females and African-Americans. However, there is significantly increased risk for SPMs by two folds for all sites. The majority were gastrointestinal SPMs with 3-fold increased risk and highly significant risk for colorectal SPMs by five folds. Thus, screening for GI SPMs after verrucous carcinoma diagnosis is necessary for early detection and better management outcome.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.