4-nitroquinoline-1-oxide (4NQO) induced oral carcinogenesis: A systematic literature review

OBJECTIVE

Based on a critical review of published studies, we aimed to develop a good practice guide for using 4-nitroquinoline-1-oxide (4NQO) as an inducer of oral carcinogenesis in Wistar rats.

DESIGN

A systematic search was performed on Medline Ovid, PubMed, Embase, Web of Science, and Scopus databases. The SYRCLE's risk of bias tool was used to assess the quality of the studies.

RESULTS

Thirty-five articles met the selection criteria; 22 (62.9%) of them administered 4NQO systemically in drinking water, with a mean concentration of 30.2 ppm (SD±15.9) and during a mean period of 20.8 (SD±7.8) weeks. The other 13 (37.1%) studies performed topical applications of 4NQO painting the oral mucosa of the animals three times a week (100%) with a mean period of administration of 16.8 (SD±7.0) weeks. Different 4NQO concentrations used for other periods achieved significant tumor development. Most studies didn't perform quantitative clinical analysis, and the histopathological diagnosis/grading criteria varied considerably.

CONCLUSIONS

A poor description of solution care, adverse effects, and the number of losses were observed, and the reporting of these features needs to be improved. Suggestions to guide the development of future research are provided.

Analysis of referrals to the stomatology service in a Southern Brazilian hospital: a retrospective study

This paper intends to describe the demand for referrals to the stomatology service requested by the medical teams for inpatients in a reference hospital in the south of Brazil. This research is a retrospective cross-sectional descriptive study focusing on data collection and assessment of information about referrals to the stomatology unit carried out from January 2008 to December 2018. All information was obtained from the hospital management software database, then transferred and analyzed individually for descriptive statistics. A total of 4433 cases were referred to the stomatology team, with an average of 403 cases by year. Hematology/hemato-oncology (37.3%) was the specialty asking for the majority of the referrals, followed by Oncology (20.4%) and Pneumology (8.2%). The mean patients' profile was males (55.5%), receiving a diagnosis of oral mucositis (43.5%), and with the first and second decades of life being the most prevalent ones (34.9%), with a mean age of 34.8±22.3 years. The most common treatment performed by the stomatology team was the photobiomodulation therapy (44.8%). This retrospective study demonstrated the important profile of the stomatological care in hospitalized patients from a specific hospital, especially referred by the hematology/hemato-oncology team. These results evidenced the importance of the stomatology specialty in the hospital environment.