|Ahead of print publication
Subjective and perceptive assessment of speech/voice and swallowing function before and after radiation therapy in patients of head-and-neck squamous cell cancer
Vasundhara V Aggarwal1, Chaitali Manohar Waghmare2, Saroj N Lolage3, Hemant J Pawar3, Meenakshi Ravichandran2, Arya Bhanu2
1 Department of Radiation Oncology, Rural Medical College, PMTPIMS, Loni, Maharashtra, India
2 Department of Radiation Oncology, Rural Medical College and Pravara Rural Hospital, PMTPIMS, Loni, Maharashtra, India
3 Department of Medical Statistics, Rural Medical College and Pravara Rural Hospital, PMTPIMS, Loni, Maharashtra, India
|Date of Submission||17-Apr-2021|
|Date of Decision||16-May-2021|
|Date of Acceptance||03-Jun-2021|
|Date of Web Publication||25-Apr-2022|
Chaitali Manohar Waghmare,
Department of Radiation Oncology, Rural Medical College and Pravara Rural Hospital, PMTPIMS, Loni, Rahata, Ahmadnagar - 413 736, Maharashtra
Source of Support: None, Conflict of Interest: None
Aim: To prospectively assess subjective and perceptive speech/voice and swallowing function before and after radiation therapy (RT) in patients of head-and-neck squamous cell cancer (HNSCC).
Materials and Methods: The study cohort comprised eligible consecutive HNSCC patients planned for curative RT from April 2018 to July 2018 who consented for the study. Prospective evaluation of speech/voice and swallowing function was done before and after RT. For subjective and perceptive evaluation of speech/voice, speech handicap index (SHI) and Grade, Roughness, Asthenia, Breathiness, and Strain (GRABS) Scale was used, respectively. For subjective and perceptive evaluation of swallowing, M D Anderson Dysphagia Inventory (MDADI) and Performance Status Scale for head and neck (PSSHN) were used, respectively. All patients were taught speech/voice and swallowing exercises before RT. Statistical analysis was performed using SYSTAT version-12 (Cranes software, Bengaluru).
Results: The study cohort comprised 30 patients of HNSCC with a median age of 57 years and male-to-female ratio of 4:1. The most common subsite was the oral cavity (43.33%) and a majority (76.66%) presented in the locally advanced stage. Post-RT there was significant improvement in speech/voice function (SHI P = 0.0006, GRABS score P = 0.003). Perceptive assessment of swallowing function by PSSHN showed significant improvement (P = 0.0032), but subjective assessment by MDADI showed no significant (P = 0.394) improvement until the first follow-up.
Conclusion: Speech/voice function improved significantly after radiotherapy when combined with rehabilitation exercises. Swallowing function did not improve till the first follow-up. Future studies with the large number of patients and long-term follow-up are needed to document the changes in organ function.
Keywords: Head-and-neck squamous cell cancer, MD Anderson Dysphagia Inventory, radiation therapy, speech handicap index, speech/voice function, swallowing function
|How to cite this URL:|
Aggarwal VV, Waghmare CM, Lolage SN, Pawar HJ, Ravichandran M, Bhanu A. Subjective and perceptive assessment of speech/voice and swallowing function before and after radiation therapy in patients of head-and-neck squamous cell cancer. J Can Res Ther [Epub ahead of print] [cited 2022 Dec 8]. Available from: https://www.cancerjournal.net/preprintarticle.asp?id=343921
| > Introduction|| |
Head-and-neck squamous cell cancers (HNSCC) are commonly treated with surgery (Sx), radiation therapy (RT), and chemotherapy (CT). Good local control of disease is well known. Hence, the choice of treatment depends on organ preservation. Thus, the role of RT is dominant. RT helps in organ preservation. However, functional alterations are known with RT,, even with highly conformal RT.,
Voice is an audible sound produced by an act of phonation while speech is a combination of phonation, resonance, and articulation. Swallowing is a process that allows the passage of food and liquids from the mouth to the throat and then to the esophagus. There is the alteration in speech/voice and swallowing function in patients of HNSCC either because of disease or the side effects of treatment.
Due to impairment in speech/voice and swallowing functions; patients suffer physically (starvation, dehydration, and aspiration pneumonia), socially (affected social eating and inability to speak fluently/communicate properly), and mentally (low self-confidence and depression). Thus, the overall health of the patient is affected and hence the quality of life (QOL).
However, we could not identify any previous study in the literature investigating the speech/voice and swallowing function simultaneously using self-reported and perceptive tools. Therefore, we undertook this prospective study to subjectively and perceptively evaluate speech/voice and swallowing function before and after RT in HNSCC patients.
| > Materials and Methods|| |
The study was approved by an institutional ethics committee (IEC) and Indian Council for Medical Research (ICMR) under short-term studentship (STS) program. The study was conducted in accordance with the ethical standards of IEC and the Helsinki declaration of 1975, as revised in 2000. Informed written consent was obtained from all the study participants.
All the consecutive nonmetastatic and nonnasopharyngeal HNSCC patients treated in the department of radiation oncology from April 2018 to July 2018 were evaluated for the study. Patients of all age groups and either sex with Karnofsky's Performance Scale ≥70, histopathologically proven HNSCC, literate Marathi speaking patients planned for curative RT who gave informed written consent and were able to complete the questionnaire, were included in the study. Patients had not seen these questionnaires before. Patients with SCC of skin/ear, speaking and swallowing difficulties due to neurological diseases/congenital or traumatic disorders, neuro-cognitive dysfunction, and previous history of head and neck RT/Sx/CT (other than for present disease) were excluded from the study.
All patients satisfying the above inclusion and exclusion criteria were treated with curative intent using radical or adjuvant RT or concurrent Chemoradiation therapy (CTRT). Patients were immobilized with thermoplastic molds and treatment fields were simulated with CT simulation. Bilateral shrinking portals using three-dimensional conformal RT were used in all except two patients. These two patients were treated with intensity-modulated RT. Dose constraints to the swallowing (dysphagia aspiration-related structures [DARS]) or voice (vocal cords) structures were not given. Radiation dose delivered was 60–66 Gy/30–33 fractions at the rate of two Gy per fraction per day over 6–7 weeks using six MV photons with or without weekly injection of Cisplatin 30 mg/m2. All patients were taught prophylactic exercises for speech/voice (as advised by the trained speech therapist) and swallowing [Table 1]; along with pumping neck exercises (for prevention of lymphedema) before starting RT and were asked to continue the same throughout the treatment and in future. During RT, all patients were assessed weekly for toxicity grading, supportive care need, and RT/prophylactic exercise compliance.
|Table 1: Prophylactic speech/voice and swallowing rehabilitation exercises|
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The subjective and perceptive assessment of speech/voice and swallowing function was made before starting RT (pre-RT) and 4–6 weeks after the conclusion of RT, i.e., at first follow-up (post-RT).
- Speech/voice function-Self-reported assessment of speech/voice function was done using linguistically validated Marathi version of speech handicap index (SHI) which was translated with prior permission from the primary author of an original English questionnaire and according to the translation guidelines by Beaton et al. It assesses speech function (11 questions), psychosocial function (14 questions), the intelligibility of speech (four questions) and financial problems (one question). The total score ranges from zero to 120 where a score of zero suggests no speech impairment and the score of 120 suggest severe speech impairment. Perceptive assessment of speech/voice was done using Grade, Roughness, Asthenia, Breathiness, and Strain (GRABS) scale where a overall grade zero suggests normal speech and overall grade three suggests severe impairment. Speech/voice was assessed for the grade (Hoarseness and overall voice quality), roughness (harshness), asthenia (hypokinetic or weak voice), breathiness (audible impression of turbulent air leakage or noise component), and strain (forceful speech/voice or vocal tension) by a trained speech and language therapist
- Swallowing function-Subjective assessment of swallowing was done using linguistically validated Marathi version of the patient's self-reported dysphagia specific MD Anderson dysphagia inventory (MDADI) (unpublished data) which was translated with prior permission from the primary author of an original English questionnaire and was according to the translation guidelines by Beaton et al. It consists of global (one question), emotional (six questions), physical (eight questions), and functional (five questions) domain. Total score ranges from 0 to 100 where higher the score; the better the function. Perceptive assessment of swallowing was made using Performance Status Scale for head-and-neck (PSSHN) cancer patients which assesses eating in public, understandability of speech, and normalcy of diet. Scores range from zero to 300. Higher score indicates better function.
All data were compiled, tabulated, and subjected to statistical analysis. Analysis was done using (SYSTAT version-12 by Cranes software, Bengaluru, Karnataka, India) by Cranes software, Bengaluru. Descriptive statistics used were percentage, mean ± standard deviation, and median. The internal consistency of the questionnaire was evaluated by calculating Cronbach's alpha coefficient. For Inferential statistics, tests of significance were applied to appropriate observations to draw inferences. Paired t-test for normal distribution and Wilcoxon matched-pairs signed-rank test for nonnormal distribution was applied when the variables were continuous. The Chi-square test was used for the assessment of discrete variables and to show association. Significance (P value) was set at the level of 0.05 to see if there was any improvement or derangement in speech/voice and swallowing function after RT and combined with prophylactic exercises.
| > Results|| |
Thirty consecutive HNSCC patients who were treated with radical or adjuvant RT/CTRT for whom prospective evaluation for speech/voice and swallowing function was done, both subjectively and perceptively, were evaluated for the study. The median age of presentation was 57 years with male-to-female sex ratio of 4:1. The most common subsite reported was oral cavity (13 patients-43.33%) and a majority of the patients presented with locally advanced disease (23 patients-76.66%). Most of the patients were treated with adjuvant RT/CTRT (16 patients-53.33%). At the time of the first physical follow-up; all except one (partial response) patient had complete response to treatment according to the response evaluation criterion in solid tumors-version 1.1. The characteristics of the study population are described in [Table 2].
Validity of questionnaire-the internal consistency or homogeneity of each questionnaire was analyzed using Cronbach's alpha coefficient in both the pre-RT and post-RT groups. Cronbach's alpha was studied for all 30 patients and 10 randomly selected patients. It was >0.7 for most of the scales suggesting high internal consistency. It was approaching 0.7 for the financial scale of SHI (0.681), and global (0.677) and physical (0.694) scales of MDADI which is considered as moderate homogeneity. There was no major difference in the homogeneity of 30 patients versus 10 randomly selected patients [Table 3]. This shows that both the questionnaires are reliable and valid when administered to the patients of HNSCC.
|Table 3: Cronbach's alpha for M D Anderson dysphagia inventory and speech handicap index|
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Pre-RT mean total score for SHI was 53.611 (±27.310) which decreased to 34.111 (±23.507) post-RT. Thus, there was significant (P = 0.0002) improvement in speech/voice when assessed subjectively. Subgroup analysis showed significant improvement in all parameters which include financial, intelligibility, social, and physical domain [Table 4]. Significant improvement (P = 0.0153) was seen in the self-rating of speech/voice by SHI [Table 5]. Maximum cases (12 patients) had GRABS overall Grade I speech/voice impairment before RT, while post-RT maximum cases (16 patients) had GRABS overall grade zero speech/voice impairment. Pre-RT GRABS overall grade III was seen in four patients while post-RT GRABS overall grade III was not seen in any of the patients. Significant improvement (Chi-square = 13.953, degree of freedom = 3, P = 0.0030) in speech/voice was seen when assessed perceptually even though the voice box was irradiated in all the patients [Figure 1].
|Table 4: Self-reported analysis of speech/voice and swallowing function using speech handicap index and M D Anderson dysphagia inventor, respectively|
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|Figure 1: Perceptive assessment of speech/voice function using Grade, Roughness, Asthenia, Breathiness and Strain scale|
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Pre-RT mean total score for MDADI was 60.148 (±20.839) which marginally increased to 60.638 (±16.167) after RT. Thus, there was no significant (P = 0.394) improvement in swallowing function on subjective assessment. On the assessment of individual parameters (Global, emotional, financial, and physical scale) significant improvement was not observed [Table 4]. The mean total score for PSSHN pre-RT was 179.83 (±65.396) which increased to 213.50 (±42.368) post-RT. Thus there was a significant (P = 0.0032) improvement in the swallowing function when assessed using perceptive scale. On subscale analysis there was significant improvement in “Understandability of speech” domain (P < 0.0001) while “eating in public” (pre-RT 56.667 ± 29.312, post-RT 60 ± 18.099, P = 0.5235) and “Normalcy of diet” (pre-RT 55.667 ± 25.688, post-RT 62.667 ± 20.833, P = 0.17000 showed borderline but nonsignificant improvement [Figure 2].
|Figure 2: Perceptive assessment of swallowing function using Performance Status Scale for head and neck|
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| > Discussion|| |
HNSCC is well managed with multimodality treatment with resultant good local control rates. Hence, organ and function preservation which indirectly affects the QOL is important. Concurrent chemoradiation therapy (CTRT) is the standard of care as organ preservation treatment modality in HNSCC. At the same time, one must keep in mind that the nonfunctioning organ preservation may be more harmful than complete excision. RT negatively affects the speech/voice and swallowing function because of RT induced salivary and sensory dysfunction, DARS injury, and fibrosis/scaring of tissue,, which further worsen if RT is given after surgery which in itself depends on the extent of surgery and reconstruction technique used. These radiation-induced side effects cannot be avoided completely even with highly conformal RT like intensity-modulated radiotherapy.,
The aim of speech/voice and swallowing rehabilitation is to first optimize function (usually by direct therapy programs such as exercise regimens) and second, to introduce compensatory strategies (diet changes, intra-oral or voice prostheses) or maneuvers (such as postural changes for safer swallowing); when improvement in function cannot, or does not occur. Speech/voice and swallowing exercises, if administered from the 1st week of chemo-radiation and thereafter continued, results in significant improvement in the function and QOL.,,
The disease in itself and the side effects of treatment are bound to have a significant impact on the patient's QOL, especially because of speech/voice and swallowing dysfunction which need to be quantified to compare treatment outcome of different treatment modalities and to add specific corrective measures for organ dysfunction. This is made possible by using patient's self-reported QOL tools or subjective assessment which correctly measures the intensity of the problem if these tools are available in patient's own language. At the same time; the organ function should be assessed using objective/semi-objective or perceptive tools by a trained clinician/speech and swallowing therapist to understand and correlate the problem effectively. In this study we assessed the organ function (speech/voice and swallowing); using and comparing both the subjective (patient's self-reported) and perceptual (as perceived by the physician) analysis. The internal consistency of both questionnaires was good which reflected its good reliability. Few subscales showed moderate internal consistency, i.e., Cronbach's alpha of less than but close to 0.7. This can be because of heterogeneity in HNSCC subsites, for example, a patient with buccal mucosa carcinoma may not complain of dysphagia while it can be a predominant complaint in patients of hypopharynx lesion. Cronbach's alpha value of close to or >0.7 in all study samples (n = 30) and randomly selected 10 patients suggested the Marathi version of the questionnaires provides reliable, stable, and consistent results.
The oral cavity is the first and fourth most common site of cancer affecting males and females of India, respectively. Maharashtra where the local spoken language is Marathi; reported the highest incidence of oral cancer in India. Maximum (43.33%) patients in our study had oral cavity as the primary site of the lesion. The maximum percentage (76.66%) of patients had stage III and IV cancer out of which the maximum were stage IV patients. In the Indian scenario, patients generally present in the advanced stage of disease which may lead to more severe organ dysfunction because of extensive disease, extensive surgery, and larger RT portals.
Post-RT speech/voice dysfunction is mainly because of xerostomia and/or scaring and fibrosis of the voice box. The subjective and perceptual analysis showed statistically significant improvement in speech/voice function post-RT and speech/voice exercises. The vocal cords were inside the RT treatment portals in all our patients without specific dose constraints. Voice quality improves immediately after RT and remained improved even at 1 year post-RT. Dzioba et al., reported worse SHI scores at 1 and 6 months postsurgery where baseline SHI scoring was done before surgery and all patients were of oral tongue cancer treated with partial glossectomy with/without adjuvant RT/CTRT. Advanced T-stage tumors of the tongue (oral/base tongue) are associated with poor speech outcomes. The post-RT voice quality will be affected in laryngeal diseases. RT for nonlaryngeal HNSCC also affects the voice quality because of unintentional irradiation of vocal cords.
The results using PSSHN showed significant improvement in swallowing function when the total score was studied. However, the subscale analysis revealed the improvement was significant only with “understandability of speech” domain while “eating in public” and “normalcy of diet” did not show significant improvement. Literature showed that when the oropharynx and hypopharynx were studied separately; swallowing function using PSSHN showed no improvement. The MDADI score improves 6 months after RT when combined with rehabilitation exercises. Our study was within the window of early post-RT changes and showed no significant improvement in MDADI score.
There are many variables that can affect subjective swallowing function evaluation. These include age-related dental status and grade of xerostomia. Swallowing dysfunction because of xerostomia has not been considered separately in MDADI. Many patients were not being able to differentiate between swallowing dysfunction and xerostomia so they combined the symptoms and answered accordingly. Patients might have answered negatively because of the depression due to the disease and/or taboo associated with cancer. Self-reported QOL which is a broad-ranging concept may be affected in a complex way by the person's physical health, psychological state, personal beliefs, social relationships, and relationship to salient features of their environment.
There are some limitations of this study. Considering STS project, the study duration was less. Hence, the long-term follow-up and function assessment was not done. The function assessment done was within the window of early post-RT changes. Relatively lower literacy rate at rural area and even the literate patients were not able to complete the questionnaire on their own as they were not in touch with reading since long, was one of the major constraints for self-reported analysis which affected the total number of study subjects. Though a lot of emphases has been given these days to dysphasia aspiration-related structures DARS and vocal cords sparing, the radiation dose constraints to these structures were not given. As the RT target is close to DARS and vocal cords, the good function outcome even after giving appropriate dose constraints during highly conformal RT is questionable., We used the GRABS scale for perceptive assessment of speech/voice which may have observer bias. However, studies have shown that there is sufficient reliability (inter-and intra-observer reproducibility) when GRABS was used clinically. Speech and voice are different but interdependent and should be assessed using different subjective and perceptive evaluation scales, i.e., voice handicap index (VHI) and GRABS for the voice and SHI and London speech evaluation scale for speech. Grossly, VHI and SHI intended to ask similar questions related to voice and speech function, respectively. The glottic region was irradiated in all study subjects with radical RT dose. Hence, the use of GRABS scale is justified.
| > Conclusion|| |
Speech/voice function improved significantly after radiotherapy for HNSCC when combined with rehabilitation exercises. The swallowing function did not improve till the time of the first follow-up. Future studies with large number and homogenous group of patients, head-and-neck subsite specific, long term follow-up and use of the structured specific multidimensional protocol for speech, voice, and swallowing assessment are needed to document the changes in organ function after treatment of HNSCC using RT.
Financial support and sponsorship
ICMR grant for STS project. Reference ID-2018-05868.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]