1 Department of Urology, Tan Tock Seng Hospital, Singapore. Electronic address: mingchunchan@hotmail.com.
2 Department of Urology, Tan Tock Seng Hospital, Singapore.
3 Department of Urology, Tan Tock Seng Hospital, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.
4 Department of Urology, Tan Tock Seng Hospital, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore; Yong Loo Lin School of Medicine, National University Singapore, Singapore.