1. Department of Pathology, National University Hospital, National University Health System, Singapore 119074, Singapore
2. Department of Pathology, Hospital Serdang, Kajang 43000, Malaysia
3. Department of Otolaryngology—Head and Neck Surgery, National University of Singapore, Singapore 119228, Singapore
4. Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore