KTP Laser in the Treatment of Early Glottic Cancer: A ... · PDF fileKTP Laser in the...
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KTP Laser in the Treatment of Early Glottic Cancer: A Viable Alternative Matthew S Broadhurst, MD, FRACS 1, 2 1 Queensland Centre for Otolaryngology & Voice, 2 St Andres War memorial Hospital INTRODUCTION DISCUSSION RESULTS 0 20 40 60 80 100 120 VHI pre VHI post MPT pre MPT post VHI and MPT T1a T1a T1a T1a T1a T1a T1a T1a T1b T1b T1b T1b Chart 1. VHI – voice handicap index MPT – maximal phonation time (seconds) Figure 3. Microlaryngoscopy view of a typical early glottic SCC. Figure 1. T1a glottic SCC before KTP laser treatment at videostroboscopy Figure 2. The same patient at 2 years with normal voice and videostroboscopy. ABSTRACT METHODS AND MATERIALS CONCLUSIONS REFERENCES CONTACT Introduction: The vast majority of early glottic cancers are treated with single modality therapy: radiation or CO2 laser surgery. An emerging technique utilising the potassium titanyl phosphate (KTP) laser also appears to be effective as a single modality treatment. The project’s aim was to assess the efficacy and voice outcomes of KTP laser in the treatment of early glottic cancer. Methods: A retrospective chart review was undertaken of consecutive patients treated with KTP laser for T1aN0M0 and T1bN0M0 early glottic cancer under a single treating surgeon . Ethics approval was granted. Patients underwent routine tumor board workup, biopsy and 2 definitive staged KTP laser treatments 6 weeks apart. Routine cancer followup was conducted with a final assessment and data collection at 2 years. Videostroboscopy was performed and the voice handicap index (VHI) form completed before surgery and at 2 years following treatment. Results: Of the 12 cancers(11 patients) included (10 male, 1 female) 8 were T1a and 4 T1b with one patient having bilateral T1a lesions. All patients completed follow up at 2 years and remained disease free. The mean VHI was 72 preoperatively improving to 19 postoperatively at 2 years. Conclusion: KTP laser provides a reasonable alternative to radiation or CO2 laser excision for T1N0M0 glottic cancer. The success rate in this pilot study is comparable to existing treatment methods and voice outcomes appear to be very good. In addition, radiotherapy was avoided preserving it as a future treatment option in all cases. This avoids the short and long term toxicity of that treatment. Twelve glottic cancers (11 patients) were included in this study with all completing the preliminary follow- up period of 2 years. There were no local or regional failures and no patients progressed to additional salvage surgery (either endoscopic or open) or radiation. At the 2 year follow-up review, all patients were alive without disease and had improved maximal phonation time. The voice quality was significantly better than pre-KTP laser treatment. Of the 12 cancers, there were 11 males and 1 female with average age 58.6years (45-76 years). Eight cancers were T1aN0Mo with 4 cancers T1bN0Mo. The voice handicap index(VHI) was 72(34-108) before treatment and at 2 years was 19(0-40). Maximal phonation time improved after treatment from 8.1 seconds (6-11) to 11.5 (7-17). Not all patients had complete pre and post aerodynamic and acoustic data so the fundamental frequency and frequency range were excluded from analysis. No patients experienced any peri-operative complications. Survival outcomes from the accepted treatment modalities for early glottic cancer(radiation and CO2 laser) have equivocal rates of cure. 2,3 Given this, other metrics such as voice outcomes become important in selecting treatment options. The photoangiolytic lasers, including KTP appear to provide similar efficacy in treatment of selected cases but have theoretical advantages in voice outcomes. 1 By enabling maximal preservation of surrounding normal vocal fold soft tissue through photoangiolysis, the surgical defect is minimised. Oncologic principles are maintained with biopsies taken from the margins to ensure adequate disease removal. Staged surgeries are 6 weeks apart In this small proof of concept study, there were no treatment failures and substantial improvements in voice outcomes. Treatment with KTP laser also enabled preservation of radiation therapy as future treatment option, should it be required. This therefore avoided the short and long term toxicity of radiation therapy in all patients. The voice outcomes at 2 years approached the normal population which is a substantial advance over traditional voice outcomes from radiation or CO2 laser therapy. Consecutive patients with early glottic squamous cell carcinoma(SCC) presenting to the author’s tertiary referral laryngology practice over 12 months were included. All patients had not undergone prior treatment of any kind. All patients were biopsy proven SCC and staged as T1aN0M0 or T1bN0M0. Stroboscopy was performed on all with high definition video recording and basic aerodynamic and acoustic measurements were obtained(maximal phonation time, pitch range, fundamental frequency). In addition, the voice handicap index(VHI) was completed prior to treatment. All patients underwent a 2 staged KTP laser microlaryngoscopy and treatment protocol separated by 6 weeks and remained disease free for the entire study period. Final results were collected at 2 years following completion of treatment. KTP laser treatment of selected early glottic cancers may provide a viable treatment modality with similar efficacy but improved vocal outcomes. It is well tolerated by patients and can preserve radiation treatment for future use should the need arise. It is feasible a large proportion of early glottic cancer patients could therefore avoid radiation as a first line treatment and with that, its short and long term toxicity. A larger study into long term outcomes from KTP laser treatment of early glottic cancer is currently underway. Treatment of early glottic squamous cell carcinoma has a high cure rate of over 90% using either of the two widely accepted modalities: radiation or transoral CO2 laser microsurgery(TLM). 2,3 Given that both are highly effective modalities, one can look to other metrics to help guide the treatment path. Voice function following treatment is very important for patients both in occupational and social settings so treatment providing maximal voice preservation is critical. The KTP laser has shown promise in treating early glottic cancer when used both as a photoangiolytic laser and as an ablative/cutting tool, much like the CO2 laser. 1 The ability of the KTP laser to permit maximal glottal tissue preservation enables optimal function of the post-surgery layered microstructure of the vocal fold. Many patients after KTP laser treatment have near normal/normal voice not requiring reconstruction and such voice outcomes exist out to 2 years. In a setting where the KTP laser is used as first line treatment, radiotherapy can be preserved as a second line modality and in doing so, may spare many patients the short and long term effects of toxicity. Larger, multi-institutional trials are needed to improve the validity of this new treatment approach now that more laryngology groups are adopting KTP laser treatment for early glottic cancer. 1. Photoangiolytic laser treatment of early glottic cancer: a new management strategy. Zeitels SM, Burns JA, Lopez-Guerra G, Anderson RR, Hillman RE. Ann Otol Rhinol Laryngol Suppl. 2008 Jul; 199:3-24. 2. Comparison of endoscopic laser resection versus radiation therapy for the treatment of early glottic carcinoma. Osborn HA, Hu A, Venkatesan V, Nichols A, Franklin JH, Yoo JH, Ceron M, Whelan F, Fung K. J Otolaryngol Head Neck Surg. 2011 Jun;40(3):200-4. 3. Treatment of early-stage glottic cancer: meta- analysis comparison of laser excision versus radiotherapy. Higgins KM, Shah MD, Ogaick MJ, Enepekides D. J Otolaryngol Head Neck Surg. 2009 Dec;38(6):603- 12. Dr Matthew Stephen Broadhurst Queensland Centre for Otolaryngolgoy & Voice Email: [email protected] Phone: +61 419 030 658 Website: www.entdoctor.com.au Figure 4. Microlaryngoscopy view after KTP laser removal.
Transcript of KTP Laser in the Treatment of Early Glottic Cancer: A ... · PDF fileKTP Laser in the...
KTP Laser in the Treatment of Early Glottic Cancer: A Viable Alternative
Matthew S Broadhurst, MD, FRACS1, 2
1Queensland Centre for Otolaryngology & Voice, 2St Andres War memorial Hospital
INTRODUCTION DISCUSSIONRESULTS
0
20
40
60
80
100
120
VHI pre VHI post MPT pre MPT post
VHI and MPT
T1aT1aT1aT1aT1aT1aT1aT1aT1bT1bT1bT1b
Chart 1. VHI – voice handicap indexMPT – maximal phonation time (seconds)
Figure 3. Microlaryngoscopy viewof a typical early glottic SCC.
Figure 1. T1a glottic SCC before KTP laser treatment at
videostroboscopy
Figure 2. The same patient at 2 years with normal voice and
videostroboscopy.
ABSTRACT
METHODS AND MATERIALS
CONCLUSIONS
REFERENCES
CONTACT
Introduction: The vast majority of early glottic cancers are treated with single modality therapy: radiation or CO2 laser surgery. An emerging technique utilisingthe potassium titanyl phosphate (KTP) laser also appears to be effective as a single modality treatment. The project’s aim was to assess the efficacy and voice outcomes of KTP laser in the treatment of early glottic cancer.
Methods: A retrospective chart review was undertaken of consecutive patients treated with KTP laser for T1aN0M0 and T1bN0M0 early glottic cancer under a single treating surgeon . Ethics approval was granted. Patients underwent routine tumor board workup, biopsy and 2 definitive staged KTP laser treatments 6 weeks apart. Routine cancer followup was conducted with a final assessment and data collection at 2 years. Videostroboscopy was performed and the voice handicap index (VHI) form completed before surgery and at 2 years following treatment.
Results: Of the 12 cancers(11 patients) included (10 male, 1 female) 8 were T1a and 4 T1b with one patient having bilateral T1a lesions. All patients completed follow up at 2 years and remained disease free. The mean VHI was 72 preoperatively improving to 19 postoperatively at 2 years.
Conclusion: KTP laser provides a reasonable alternative to radiation or CO2 laser excision for T1N0M0 glottic cancer. The success rate in this pilot study is comparable to existing treatment methods and voice outcomes appear to be very good. In addition, radiotherapy was avoided preserving it as a future treatment option in all cases. This avoids the short and long term toxicity of that treatment.
Twelve glottic cancers (11 patients) were included in this study with all completing the preliminary follow-up period of 2 years. There were no local or regional failures and no patients progressed to additional salvage surgery (either endoscopic or open) or radiation. At the 2 year follow-up review, all patients were alive without disease and had improved maximal phonation time. The voice quality was significantly better than pre-KTP laser treatment.
Of the 12 cancers, there were 11 males and 1 female with average age 58.6years (45-76 years).
Eight cancers were T1aN0Mo with 4 cancers T1bN0Mo. The voice handicap index(VHI) was 72(34-108) before treatment and at 2 years was 19(0-40). Maximal phonation time improved after treatment from 8.1 seconds (6-11) to 11.5 (7-17).
Not all patients had complete pre and post aerodynamic and acoustic data so the fundamental frequency and frequency range were excluded from analysis.
No patients experienced any peri-operative complications.
Survival outcomes from the accepted treatment modalities for early glottic cancer(radiation and CO2 laser) have equivocal rates of cure.2,3
Given this, other metrics such as voice outcomes become important in selecting treatment options.
The photoangiolytic lasers, including KTP appear to provide similar efficacy in treatment of selected cases but have theoretical advantages in voice outcomes.1 By enabling maximal preservation of surrounding normal vocal fold soft tissue through photoangiolysis, the surgical defect is minimised. Oncologic principles are maintained with biopsies taken from the margins to ensure adequate disease removal. Staged surgeries are 6 weeks apart
In this small proof of concept study, there were no treatment failures and substantial improvements in voice outcomes. Treatment with KTP laser also enabled preservation of radiation therapy as future treatment option, should it be required. This therefore avoided the short and long term toxicity of radiation therapy in all patients. The voice outcomes at 2 years approached the normal population which is a substantial advance over traditional voice outcomes from radiation or CO2 laser therapy.
Consecutive patients with early glottic squamous cell carcinoma(SCC) presenting to the author’s tertiary referral laryngology practice over 12 months were included.
All patients had not undergone prior treatment of any kind. All patients were biopsy proven SCC and staged as T1aN0M0 or T1bN0M0.
Stroboscopy was performed on all with high definition video recording and basic aerodynamic and acoustic measurements were obtained(maximal phonation time, pitch range, fundamental frequency). In addition, the voice handicap index(VHI) was completed prior to treatment.
All patients underwent a 2 staged KTP laser microlaryngoscopy and treatment protocol separated by 6 weeks and remained disease free for the entire study period. Final results were collected at 2 years following completion of treatment.
KTP laser treatment of selected early glottic cancers may provide a viable treatment modality with similar efficacy but improved vocal outcomes. It is well tolerated by patients and can preserve radiation treatment for future use should the need arise. It is feasible a large proportion of early glottic cancer patients could therefore avoid radiation as a first line treatment and with that, its short and long term toxicity. A larger study into long term outcomes from KTP laser treatment of early glottic cancer is currently underway.
Treatment of early glottic squamous cell carcinoma has a high cure rate of over 90% using either of the two widely accepted modalities: radiation or transoral CO2 laser microsurgery(TLM).2,3 Given that both are highly effective modalities, one can look to other metrics to help guide the treatment path. Voice function following treatment is very important for patients both in occupational and social settings so treatment providing maximal voice preservation is critical.
The KTP laser has shown promise in treating early glottic cancer when used both as a photoangiolytic laser and as an ablative/cutting tool, much like the CO2 laser.1 The ability of the KTP laser to permit maximal glottal tissue preservation enables optimal function of the post-surgery layered microstructure of the vocal fold. Many patients after KTP laser treatment have near normal/normal voice not requiring reconstruction and such voice outcomes exist out to 2 years.
In a setting where the KTP laser is used as first line treatment, radiotherapy can be preserved as a second line modality and in doing so, may spare many patients the short and long term effects of toxicity.
Larger, multi-institutional trials are needed to improve the validity of this new treatment approach now that more laryngology groups are adopting KTP laser treatment for early glottic cancer.
1. Photoangiolytic laser treatment of early glottic cancer: a new management strategy.Zeitels SM, Burns JA, Lopez-Guerra G, Anderson RR, Hillman RE. Ann Otol Rhinol Laryngol Suppl. 2008 Jul; 199:3-24.
2. Comparison of endoscopic laser resection versus radiation therapy for the treatment of early glottic carcinoma. Osborn HA, Hu A, Venkatesan V, Nichols A, Franklin JH, Yoo JH, Ceron M, Whelan F, Fung K. J Otolaryngol Head Neck Surg. 2011 Jun;40(3):200-4.
3. Treatment of early-stage glottic cancer: meta-analysis comparison of laser excision versus radiotherapy.
Higgins KM, Shah MD, Ogaick MJ, Enepekides D. J Otolaryngol Head Neck Surg. 2009 Dec;38(6):603-12.
Dr Matthew Stephen BroadhurstQueensland Centre for Otolaryngolgoy
& VoiceEmail: [email protected]: +61 419 030 658Website: www.entdoctor.com.au
Figure 4. Microlaryngoscopy view after KTP laser removal.
