Using this base class you can handle your messages without extracting them first from the context. Context is still available.

BaseHandler.cs

using System.Threading.Tasks;
using MassTransit;

namespace Demo.MassTransit
{
    public abstract class BaseHandler<T> : IConsumer<T> where T : class
    {
        protected ConsumeContext<T> Context { get; private set; }

        public abstract Task Handle(T message);

        public Task Consume(ConsumeContext<T> context)
        {
            Context = context;
            return Handle(context.Message);
        }
    }
}