What is the fine-grained topic of the following text: With 50 kilometres to go, the pack caught the escapees and moments later Primoz Roglic (LottoNL-Jumbo) attacked and was joined a couple of kilometres later by Vincenzo Nibali (Bahrain-Merida), Egan Bernal (Sky) and Thibaut Pinot (Groupama-FDJ). Only return the topic.
Cycling race events