Primary vaginal malignancies: a single oncology centre experience

Primary vaginal malignancies constitute a rare entity. The aim of this study was to review all primary vaginal malignancies diagnosed in an oncologic referral centre over 11 years. A total of 35 cases were retrospectively analysed, including clinical and MRI features. Squamous cell carcinoma (SCC) was the most frequent histologic subtype (77.1%), followed by adenocarcinoma (14.3%). There was no statistically significant difference for the mean age at diagnosis or for the mean largest diameter of the tumour. Most SCCs (95%) were homogeneous on T2-weighted imaging, while all adenocarcinomas were heterogeneous (p = .0001). Concerning location, both SCCs (59.3%) and adenocarcinomas (80%) occurred more often on the upper third. However, regarding the wall of origin, all adenocarcinomas originated on the anterior vaginal wall (p = .0002), while SCCs (62.5%) had a predisposition for the posterior wall (p = .017). Regarding the history of previous hysterectomy, in the SCC group, 73.3% of patients with previous hysterectomies had cervical dysplasia (p = .018). Impact statement What is already known on this subject? MRI plays an important role in the initial approach of primary vaginal malignancies. In previous studies, it is said that SCCs usually appear homogeneous on T2WI, with the intermediate-high signal, while adenocarcinomas are often homogeneously hyperintense. Regarding location, it is known that SCCs usually arise from the posterior wall of the upper third, while adenocarcinomas often originate on the anterior wall of the proximal third. What do the results of this study add? In this study, we found that all of our cases of adenocarcinomas were heterogeneous on T2WI, with high-signal intensity areas, while SCCs were predominantly homogeneous, and this association was statistically significant. We could also confirm the data in the literature regarding the most common location of these tumours. This study also showed an association between vaginal SCC and a previous hysterectomy with cervical dysplasia. What are the implications of these findings for clinical practice and/or further research? The histologic type of vaginal malignancy has clinical and management impact. Although MRI is usually performed after histologic characterisation, this is not always the case. We think that this study can constitute a starting point to better understand the MRI features of these rare tumours. Although this technique will obviously never preclude histologic characterisation, it may provide some initial hint on the type of tumour and its aggressiveness.