“…Provenzano et al reported that collagen density may promote mammary tumour initiation and progression (Provenzano et al, 2008), Xiong et al showed that collagen was fragmented and disordered in squamous cell carcinoma as well as basal cell carcinoma of human skin, but it was broadened and well distributed in normal skin (Xiong et al, 2011), whereas Nadiarnykh et al and Kirkpatrick et al found that malignant tissue had more ordered and regularly packed collagen as compared to normal tissue (Kirkpatrick et al, 2007;Nadiarnykh et al, 2010). Moreover, it was also observed that there would be a loss of collagen in neoplasia of lungs, rectum, oropharynx and oesophagus (Meyer et al, 2013;Xu et al, 2013;Chen et al, 2014;Yan et al, 2014).…”