PhD ceremony Mr. J.K. Smit: Response evaluation of chemoradiotherapy in esophageal cancer

PhD ceremony: Mr. J.K. Smit, 16.15 uur, Academiegebouw, Broerstraat 5, Groningen

Dissertation: Response evaluation of chemoradiotherapy in esophageal cancer

Promotor(s): prof. J.Th.M. Plukker, prof. R.P. Coppes, prof. H. Hollema

Faculty: Medical Sciences

The studies described in this thesis provide insight into a better assessment of recurrences and in the prediction of response following primary (chemo)radiotherapy or neoadjuvant chemoradiotherapy in esophageal cancer patients. It is well recognized that recurrence rate and time interval to recurrence are mainly related to tumor stage and several histological risk factors, including tumor type and grade. With respect to the accuracy of assessing recurrences with the traditional Tumor-Node-Metastasis (TNM)-classification, there is a particular interest in the additional information of locoregional nodal metastasis stratification in estimating recurrence free survival, as also is described in this thesis.

Data on the prediction of recurrence free survival in patients treated with neoadjuvant chemoradiotherapy and stratified/staged according to the TNM 7th edition, as collected in this thesis, is highly important for the scientific community. It became apparent that locoregional lymph node status stratification also contains important information on the prediction of recurrence in this patient category. Interestingly, the impact on (recurrence free)- survival of locoregional lymph node status (N-status in the TNM-classification) stratification is even greater than the depth of primary tumor invasion, the T-status in the TNM-classification. Indeed, in this thesis we provide intriguing data to this theory, in which neoadjuvant treated patients, who showed (nearly) complete responses, nodal micrometastatic disease had a huge negative impact on (disease free)- survival.