Castmates mourn sitcom legend

"After an op in October to remove the tumour I had chemo to help prevent the cancer returning. During this chemo, another tumour was discovered in my liver.

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"Luckily for me this cancer was unconnected to the lung cancer and was also treatable."

In a later message to fans following treatment, he added: "Thanks to the brilliant doctors and nurses of our NHS, I will hopefully be there at next year's convention."