The reporter described that the doner tube broke during thawing.When a frozen mobilized cellular sample was thawed at hospital, the staff observed that the donor tube was broken down from the end part and thus the sample could not be used any more.The patient was treated with backup material.The bag was overfilled (25ml instead of a maximum of 20ml) and no overwrap bag was used to raise safety.This is the first complaint for this lot with a incident rate below (b)(4).