2018 Section 6 - Laryngology, Voice Disorders, and Bronchoesophalogy

by De Santis et al. found no difference in 5-year disease- free survival, overall survival, or laryngeal preservation for patients with T1 and T2 carcinoma treated with TLM versus radiation. 19 A meta-analysis of voice out- comes by Greulich et al. showed similar subjective and objective outcomes between TLM and EBRT. 20 One of the ongoing goals in management of laryngeal cancer is stratification of patients into high- and low-risk groups. Low-risk patients may be candidates for more focused treatment, such as KTP laser ablation, to main- tain oncologic efficacy while reducing side effects and pre- serving voice and swallowing, whereas higher-intensity regional treatment, such as radiation, can be selected to prevent tumor recurrence in high-risk patients. Despite this potential utility, there are currently no consensus markers for risk stratification in early glottic cancer. The link between tobacco use and squamous cell car- cinoma of the aerodigestive tract has been firmly estab- lished, but in this study neither the presence of active smoking nor history of increased years of smoking was shown to affect response rates to EBRT or KTP-TLM. Interestingly, one study found a subgroup of patients with a more papillary type of vocal fold carcinoma was identi- fied with no tobacco use history, and it has been speculated this may be due to human papillomavirus infection. 21 Anterior commissure involvement has been shown to be a risk factor for recurrence of early glottic carcinomas 22–24 ; however, our study did not see a significant increase in recurrence risk with anterior commissure involvement in either group. Limitations of the Study As this is a retrospective study, we cannot eliminate the effect of selection bias for patients who received radia- tion versus those who received KTP-TLM. Healthier patients with smaller tumors could be deemed better sur- gical candidates, whereas radiation could be reserved for larger, more diffuse tumors that would have a poorer prog- nosis. On the other hand, some patients can be deemed too sick to undergo a course of primary radiation and are offered surgery instead. Bias was also partially mitigated by the fact that patients were ultimately offered a choice between both treatments. The small sample size and the difference in follow-up lengths may also have prevented detecting true differences between the two treatment groups. There was a significant amount of missing data for voice outcomes, including for the vast majority of the patients treated with radiation, which precluded our ability to compare functional outcomes between the two groups. CONCLUSION KTP transoral microsurgical ablation of T1 glottic squamous cell carcinoma is a modality that is equally efficacious as primary radiation therapy and one which provides adequate oncologic outcomes. Preliminary voice

data suggest that KTP-TLM affords acceptable functional outcomes as well, but this will need to be assessed in a pro- spective trial comparing these results to patients receiving EBRT. BIBLIOGRAPHY 1. Overgaard J, Jovanovic A, Godballe C, Grau Eriksen J. The Danish Head and Neck Cancer database. Clin Epidemiol 2016;8:491–496. 2. Hoffman HT, Porter K, Karnell LH, et al. Laryngeal cancer in the United States: changes in demographics, patterns of care, and survival. Laryn- goscope 2006;116(9 pt 2 suppl 111):1–13. 3. Marur S, Forastiere AA. Head and neck squamous cell carcinoma: update on epidemiology, diagnosis, and treatment. Mayo Clin Proc 2016;91:386–396. 4. Howlader N, Noone AM, Krapcho M, et al., eds. SEER Cancer Statistics Review, 1975-2013. Bethesda, MD: National Cancer Institute. Available at: http://seer.cancer.gov/csr/1975_2013. Published April 2016. Updated September 12, 2016. Accessed April 10, 2017. 5. Henley SJ, Thomas CC, Sharapova SR, et al. Vital signs: disparities in tobacco-related cancer incidence and mortality—United States, 2004- 2013. MMWR Morb Mortal Wkly Rep 2016;65:1212–1218. 6. Barbu AM, Burns JA, Lopez-Guerra G, Landau-Zemer T, Friedman AD, Zeitels SM. Salvage endoscopic angiolytic KTP laser treatment of early glottic cancer after failed radiotherapy. Ann Otol Rhinol Laryngol 2013; 122:235–239. 7. Hartl DM, Brasnu DF. Contemporary surgical management of early glottic cancer. Otolaryngol Clin North Am 2015;48:611–625. 8. Fink DS, Sibley H, Kunduk M, et al. Subjective and objective voice out- comes after transoral laser microsurgery for early glottic cancer. Laryn- goscope 2016;126:405–407. 9. Murono S, Endo K, Kondo S, Wakisaka N, Yoshizaki T. Oncological and functional outcome after transoral 532-nm pulsed potassium-titanyl- phosphate laser surgery for T1a glottic carcinoma. Lasers Med Sci 2013; 28:615–619. 10. Zeitels SM, Burns JA, Lopez-Guerra G, Anderson RR, Hillman RE. Photo- angiolytic laser treatment of early glottic cancer: a new management strategy. Ann Otol Rhinol Laryngol Suppl 2008;199:3–24. 11. Zeitels SM, Burns JA. Oncologic efficacy of angiolytic KTP laser treatment of early glottic cancer. Ann Otol Rhinol Laryngol 2014;123:840–846. 12. Weiss BG, Ihler F, Pilavakis Y, et al. Transoral laser microsurgery for T1b glottic cancer: review of 51 cases. Eur Arch Otorhinolaryngol 2017;274: 1997–2004. 13. Day AT, Sinha P, Nussenbaum B, Kallogjeri D, Haughey BH. Management of primary T1-T4 glottic squamous cell carcinoma by transoral laser microsurgery. Laryngoscope 2017;127:597–604. 14. Rancati T, Schwarz M, Allen AM, et al. Radiation dose-volume effects in the larynx and pharynx. Int J Radiat Oncol Biol Phys 2010;76(3 suppl): S64–S69. 15. Fu KK, Woodhouse RJ, Quivey JM, Phillips TL, Dedo HH. The signifi- cance of laryngeal edema following radiotherapy of carcinoma of the vocal cord. Cancer 1982;49:655–658. 16. Lim YJ, Wu HG, Kwon TK, et al. Long-term outcome of definitive radio- therapy for early glottic cancer: prognostic factors and patterns of local failure. Cancer Res Treat 2015;47:862–870. 17. Cox JD, Stetz J, Pajak TF. Toxicity criteria of the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC). Int J Radiat Oncol Biol Phys 1995; 31:1341–1346. 18. Mo HL, Li J, Yang X, et al. Transoral laser microsurgery versus radiother- apy for T1 glottic carcinoma: a systematic review and meta-analysis. Lasers Med Sci 2017;32:461–467. 19. De Santis RJ, Poon I, Lee J, Karam I, Enepekides DJ, Higgins KM. Com- parison of survival between radiation therapy and trans-oral laser microsurgery for early glottic cancer patients; a retrospective cohort study. J Otolaryngol Head Neck Surg 2016;45:42. 20. Greulich MT, Parker NP, Lee P, Merati AL, Misono S. Voice outcomes fol- lowing radiation versus laser microsurgery for T1 glottic carcinoma: sys- tematic review and meta-analysis. Otolaryngol Head Neck Surg 2015; 152:811–819. 21. Zeitels SM. Glottic cancer: a metamorphosing disease. Ann Otol Rhinol Laryngol 2016;125:452–456. 22. Hakeem AH, Tubachi J, Pradhan SA. Significance of anterior commissure involvement in early glottic squamous cell carcinoma treated with trans-oral CO2 laser microsurgery. Laryngoscope 2013;123:1912–1917. 23. Eskiizmir G, Baskın Y, Yalc¸ın F, Ellidokuz H, Ferris RL. Risk factors for radiation failure in early-stage glottic carcinoma: a systematic review and meta-analysis. Oral Oncol 2016;62:90–100. 24. Chone CT, Yonehara E, Martins JE, Altemani A, Crespo AN. Importance of anterior commissure in recurrence of early glottic cancer after laser endo- scopic resection. Arch Otolaryngol Head Neck Surg 2007;133:882–887.

Laryngoscope 00: Month 2017

Ahmed et al.: KTP Laser vs. Radiation for T1 Glottic Cancer

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