1. Recipient of the John S. Schlesinger Surgery Prize. Used for travel expenses to accept post in London, 1979‑1980.
 Projects completed there:
           1. A correlation of the pathology of carcinoma of the larynx with pre‑operative computed tomography (CT) scans (Published).
           2. Histological examination of the pathological laryngeal specimen by a new method (Published).
           3. Respiratory function tests in the laryngectomee, correlated with stomal size (Published).
  
2. The use of the Pectoralis Major Myocutaneous Flap for the reconstruction of patients after major ablative cancer surgery (Published).
  
3. Carcinoma of the Larynx: particular reference to cartilage invasion by cancer, and computed tomography of the larynx.
 
Study and thesis for PhD (Med) degree. Defended July 1986. Grants from the S.A. Cancer Association, numbers RE6661 450577 and ME 6670 253599.
 
Supervisors for PhD. Professor D. Haynes (deceased, previous Professor and Head of Otolaryngology, Wits University) and Professor James Murray (deceased, previous Director, the South African Institute for Medical Research, Johannesburg).
 
 Graduated PhD degree, University of The Witwatersrand, Johannesburg. Dec. 3, 1987.
  
4. The use of the Blom‑Singer voice restoration prosthesis in laryngectomised patients. Recipient of grant from S.A. Cancer Association.(Ref. CS 2588, 16 August, 1982)
  
5. The use of pre‑operative chemotherapy and radiation therapy in the management of advanced squamous carcinoma of the head and neck (Mitomycin-C and 5-fluoro-uracil). Phase I study completed, 1983.
  
6. The use of the Trapezius osteomyocutaneous flap for the reconstruction of the mandible after ablative cancer surgery (Published).
  
7. The use of the Laser in the management of patients with laryngo‑tracheal stenosis (Published).
  
8. The value of the Flow‑Volume loop in the assessment of treatment results in laryngo‑tracheal reconstruction (published).
  
9. Supraglottic Laryngeal Cancer - a 10 year study in the Netherlands Cancer Institute; Radiation and supraglottic laryngectomy (published).
  
10. The use of the PROVOX® voice rehabilitation system in voice rehabilitation in post-laryngectomised patients (published).
  
11. The management of neck disease in supraglottic cancer. (Published)
  
12. The optimal construction of and the revision of the tracheostoma with particular reference to voice rehabilitation. (Published)
  
13. The treatment of small head and neck primary cancers with primary radiation with neck dissection for the nodal disease. (Published)
  
14. The use of SPECT scanning with 201Tl in head and neck cancer. Started study in Amsterdam (2 publications). Ongoing study at University of Stellenbosch, Vermaak B, Vlantis A, Ellman A & Gregor, RT.
  
15. Control of postlaryngectomy pharyngo-oesophageal spasm in obtaining good speech rehabilitation: a prospective analysis of two types of pharyngeal repair at laryngectomy. Louw W & Gregor RT.
  
16. Chemotherapy in nasopharyngeal carcinoma. Review: De Villiers E, Vernimmen F & Gregor, RT.
  
17. US-FNA in assessing cervical metastases in head and neck cancer. Knappe M & Gregor, RT
  
18. US in diagnosing local spread of cancer of the larynx or hypopharynx. Knappe M & Gregor, RT
  
19. The use of laser resection plus active neck management in larger tumours of the larynx and hypopharynx. (After Wolfgang Steiner, Göttingen, Germany). Penning R, Lehmann K & Gregor, RT.
  
20. The use of the second generation PROVOX prosthesis (PROVOX-2®) in patients previously rehabilitated with non-indwelling prostheses. Oudes M, Elliot M, Vlantis A & Gregor RT.
  
21. The use of Mitomycin-C in reducing fibrosis in laryngotracheal stenosis surgery. Laser and open approaches. Rzepecka O, Mansab Z & Gregor, RT
   
22. Investigation of P53 mutation in Head and Neck Cancer in SA, a pilot study. Lehmann K and Gregor, RT
  
23. Localisation of sentinel nodes in supraglottic carcinomas. Pentz A & Gregor, RT.
  
24. Multicentre Trial: Comparison of IA Chemoradiation with IV Chemoradiation in advanced H&N Cancer. Principle investigator, Waikato Hospital. Main contributor: The Dutch National Cancer Institution (NKI) Amsterdam, The Netherlands. Trial completed end of 2005.
  
25. Prognostic markers in squamous cell carcinoma of the head and neck, Indu Gunawardena, Michael Jameson, Duncan Lamont, Gregor, RT