Assessing quality of life in patients with head and neck cancer: cross-validation of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Head and Neck module (QLQ-H&N35)

Assessment of quality of life of nasopharyngeal carcinoma patients with EORTC QLQ-C30 and H&N-35 modules

PURPOSE

The current study reports on long-term quality of life (QoL) status after conventional radiotherapy in 187 nasopharyngeal carcinoma patients from 14 centers in Turkey.

PATIENTS AND METHODS

Patients with the diagnosis of nasopharyngeal carcinoma, who were treated in 14 centers in Turkey with minimum 6 months of follow-up and were in complete remission, were asked to complete Turkish versions of EORTC QLQ-C30 questionnaire and the HN-35 module. Each center participated with the required clinical data that included age at diagnosis, gender, symptoms on admission, follow-up period, treatment modalities, radiotherapy dose, and AJCC 1997 tumor stage. Each patient's 33 QoL scores, which included function, global health status, and symptoms, were calculated as instructed in EORTC QLQ-C30 scoring manual. All of the scales and single-item measures range from 0 to 100. A high score represents a higher response level. Kruskal-Wallis and Mann-Whitney U nonparametric tests were used for comparisons.

RESULTS

One hundred eighty-seven patients with median age of 46 years (range, 16-79 years) participated and completed the questionnaires. Median follow-up time was 3.4 years (range, 6 months-24 years). All patients have received external-beam radiotherapy. Beside external-beam radiotherapy, 59 patients underwent brachytherapy boost, 70 patients received concomitant chemotherapy, and 95 patients received adjuvant/neoadjuvant chemotherapy. Most of the patients in the analysis (75%) were in advanced stage (Stage III, n = 85 [45.4%]; Stage IV, n = 55 [29%]). Mean global health status was calculated as 73. Parameters that increased global health status were male gender, early-stage disease, and less than 4-year follow-up (p < 0.05). Functional parameters were better in males and in early-stage disease. Factors that yielded better symptom scores were short interval after treatment (10 scores), male gender (7 scores), and lower radiation dose (6 scores). Neoadjuvant or adjuvant chemotherapy did not have any effect on QoL, whereas concomitant chemotherapy adversely affected 5 symptom scores.

CONCLUSION

Quality of life is adversely affected in our nasopharyngeal carcinoma patients treated with combined therapies. The factors that adversely affect quality of life are advanced tumor stage, female gender, and long-term follow-up. Further controlled studies to evaluate both preradiotherapy and postradiotherapy status are necessary to clarify the contribution of each treatment modality to QoL.

Changing Quality of Life in Patients with Advanced Head and Neck Cancer after Primary Radiotherapy or Chemoradiation

OBJECTIVE

The purpose of this study was to investigate the longitudinal changes in quality of life (QoL) for patients with advanced stage (stage III or IV) head and neck squamous cell carcinoma (HNSCC) following primary radiotherapy (RT) or concomitant chemoradiotherapy.

METHODS

From January 2001 to January 2003, 149 patients with advanced HNSCC were enrolled. The data pertaining to their QoL were collected using the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire (EORTC QLQ-C30) and the EORTC Head and Neck Module (QLQ-H&N35) before and 1 year after RT.

RESULTS

Sixty-eight (46%) patients dropped out during the study period. Thirty-nine (57%) of them died of cancer. Those who were older, stage IV, treated by RT alone, or had worse pretreatment EORTC QoL scales were significantly more likely to drop out. For those completing the study, only the problems of swallowing, dry mouth, and sticky saliva were found to become more serious with both statistical (p < 0.05) and clinical (difference >10 points) significance 1 year after RT. Those subjects with cancer at the hypopharynx/larynx had a 3.3-fold higher probability to report an improvement in global QoL (95% confidence interval, CI: 1.11-6.82) than those with cancer at the oral cavity/oropharynx. Those alive without cancer 1 year after RT had a 3.6-fold higher probability to report an improvement in global QoL (95% CI: 1.32-7.13) than those alive with cancer.

CONCLUSION

The study showed a high dropout rate in this longitudinal QoL study for patients with advanced HNSCC. Pretreatment cancer sites and living with cancer or not after treatment significantly affected the change in global QoL 1 year after RT.

Obstructive sleep apnea and head and neck neoplasms

OBJECTIVE

To elaborate the relationship between obstructive sleep apnea (OSA) and head and neck neoplasms (HNN).

STUDY DESIGN AND SETTING

A systematic review of the MEDLINE literature.

RESULTS

Thirty of 34 articles indexed under OSA and HNN were about neoplasms that presented first as OSA. Four of the articles were about treatment of HNN causing OSA and gave incidences varying from 8% to 92%. Quality of life surveys confirm that patients with malignant HNN have sleep problems. Xerostomia may contribute to these sleep problems, and the role of salivary mucins deserves consideration.

CONCLUSIONS

This review of the literature raises several new research questions about the clinical and biological relationships between OSA and HNN.

A pilot study of the translation, cultural adaptation and validation of the EORTC head and neck cancer quality of life questionnaire module (QLQ-H&N35) for use in Japan

Development of the Japanese version of the European Organisation for Research and Treatment of Cancer (EORTC) quality of life questionnaire (QLQ)-head and neck 35 (H&N35) module for use in Japan. Phase 1: The First Intermediary Japanese version was produced according to the EORTC Quality of Life (QOL) Unit translation project guideline. The Second Intermediary version was a result of the backward translation project and two peer-to-peer discussion settings by health care professionals related to the project. Phase 2: Focus group discussions with team members and semi-structured interviews with 108 participants to produce the final Japanese version. Our cultural-adaptation and validation yielded scores that are reliable by internal consistency (Cronbach's alpha) and the validation results showed acceptable correlation results by Pearson's Product Moment Correlation Coefficient (r). The questionnaire was well accepted and the response rate was high (93.9%). Convergent validity was moderate to high (from r=0.55 to 0.97, P<0.01) and discriminant validity was low; Cronbach's alpha coefficients of most scales had good reliability (alpha> or =0.70), except that of pain scale. In Japan, however, some correlation patterns between scales differed from that in the original European countries and cultures. The use of both qualitative and quantitative methods was important in developing the Japanese version of the QLQ-H&N35 module. We conclude that the Japanese version has good psychometric validity, thus it is recommended for further study to assess health-related quality of life (HRQOL) in Japanese head and neck cancer patients.

Mood, anxiety and sense of humor in head and neck cancer patients in relation to disease stage, prognosis and quality of life

CONCLUSION

At diagnosis, control patients had the lowest depression levels and anxiety scores, followed by those with limited HNSCC disease and these with extended HNSCC disease. Anxiety and depression levels at diagnosis predicted prognosis via an association with extent of disease. Sense of humor, but not anxiety or depression level, predicted lower QoL and depression levels at follow-up.

OBJECTIVE

To study the association between anxiety score, depression level at sense of humor at diagnosis in head and neck squamous cell carcinoma (HNSCC) patients versus TNM stage, prognosis and depression level/quality of life (QOL) 6 years following diagnosis. A control group of patients with benign HN disease was also included.

MATERIAL AND METHODS

Male patients with newly diagnosed HNSCC (n =78) or benign HN (n =61) disease completed the following questionnaires: the Beck Depression Inventory, the Spielberger Trait Anxiety Inventory (state) and the Svebak humor questionnaire. Patients with cachexia or those aged >80 years were excluded. In the HNSCC patients, TNM stage, prognosis and QOL/depression level (n =27) were determined following successful therapy.

RESULTS

HNSCC patients reported high anxiety scores and lower depression levels than control patients, although there was overlap between the groups. N stage was associated with high anxiety scores and depression levels, whereas T stage was only associated with depression levels. Both anxiety scores and depression levels at diagnosis predicted prognosis through an association with TNM stage. Sense of humor, but not depression levels or anxiety scores, at diagnosis predicted QoL and depression levels at follow-up.

Quality of life assessment in laryngectomized individuals: do we need additions to standard questionnaires in specific clinical research projects?

OBJECTIVES

To assess, whether the EORTC questionnaires QLQ-C30 and QLQ-H&N35 give enough detailed information to study specific quality of life (QoL) related issues in laryngectomized individuals.

DESIGN

Multicentre, prospective clinical trial; baseline measurement with EORTC questionnaires and an additional questionnaire, focusing on specific postlaryngectomy problems.

SETTING

Head and Neck Department of one Comprehensive Cancer Center and three Academic Medical Hospitals in the Netherlands.

PARTICIPANTS

Eighty laryngectomized individuals, selected to participate in a prospective clinical trial on hands-free tracheoesophageal speech.

MAIN OUTCOMES MEASURES

Comparison of QoL dimensions, as assessed with the standard EORTC questionnaires, with the information obtained with additional questions, aimed at discovering in more detail, e.g. voice and respiratory problems in laryngectomized individuals.

RESULTS

Based on the EORTC QoL questionnaires a good overall and voice specific QoL-level was found. However, the additional questionnaire showed that especially concerning voice and respiration more specific information was obtained. For example, despite an overall satisfaction with many aspects of the voice in more than three-quarters of the patients, speaking in a noisy environment was reported by 63% of the patients as being a serious problem, and a significant relation could be established between pulmonary and voicing problems (r = 0.28, P < 0.05), something also undetectable with the EORTC questionnaires.

CONCLUSIONS

These findings underline the necessity to develop and use more specific additional questionnaires as an adjunct to the existing EORTC questionnaires, when studying specific symptoms in laryngectomized individuals, especially in order to detect intervention related changes over time.

Irradiation impairment of umami taste in patients with head and neck cancer

BACKGROUND

Previous studies have reported the alteration of the four basic tastes (sweet, salty, sour and bitter) in patients with head and neck cancer (HNC) during radiotherapy. However, there has been no investigation on the function of umami taste, a novel basic taste recognized recently, during head and neck irradiation.

OBJECTIVE

To investigate the recognition threshold of umami and the four basic tastes at different irradiation dose intervals during radiotherapy for head and neck cancer.

METHODS

In 30 patients with malignant neoplasm of head and neck, objective taste thresholds were examined by use of a whole-mouth method at pre-radiotherapy, irradiation doses at 15, 30, 45, and 60 Gy, respectively. Subjective taste loss and some distresses were recorded simultaneously.

RESULTS

Sweet, sour, salty, and bitter tastes showed temporarily and slightly increased thresholds during the treatment, but no statistical difference was found between the threshold at pre-radiotherapy and that at 15, 30, 45, and 60 Gy in any taste quality (all P > 0.05). Significantly impaired threshold of umami taste was revealed at 30 Gy (P < 0.05) and remained throughout the following treatment (at 45 and 60 Gy, both P < 0.01). Subjective taste impairment, appetite loss and satisfaction with the current state tended to deteriorate significantly during the irradiation. Mean body weight of the patients experienced a continuous loss, decreasing from an average of 60.4 kg before treatment to 57.3 kg at 60 Gy (P < 0.01). Scores of satisfaction with current state showed a significant correlation with umami taste thresholds (P = 0.035).

CONCLUSION

The clinical impairment pattern of umami taste is different from that of the other four basic tastes in HNC patients during radiotherapy. Impaired umami taste acuity plays an important role in impacting the quality of life of the patients irradiated to the head and neck.

A randomized phase II trial of amifostine for head and neck irradiation in lymphoma

Acute and long-term oral complications occur in patients receiving mantle radiation therapy or irradiation to the head and neck region for Hodgkin's disease or non-Hodgkin's lymphoma. While considerable data are available on the effect of radiation therapy on the oral function and quality of life of patients with squamous cell carcinoma of the head and neck, such information is lacking for similarly irradiated lymphoma patients. In this article we discuss the rationale and study design of an ongoing, randomized phase II study evaluating the role of amifostine (Ethyol; Medimmune Inc, Gaithersburg, MD) as a radiation protectant in patients receiving head and neck irradiation for lymphoma. Further investigation in this lymphoma population is needed to improve our understanding of the extent of the problem and its impact on patients' daily living and functioning. Importantly, fine-tuning the treatment and management approaches to minimize morbidity while maximizing the survival and quality of life of patients are crucial next steps.

Quality of life and illness perceptions in patients with recently diagnosed head and neck cancer

BACKGROUND

The purpose of this study was to investigate which illness perceptions of patients recently diagnosed with head and neck cancer explain variance in their quality of life (QOL) to identify potential targets for interventions aimed at improving QOL.

METHODS

Sixty-eight patients (mainly with stage III and IV disease) completed the Illness Perception Questionnaire-Revised (IPQ-R) and the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30).

RESULTS

Pretreatment cross-sectional results from this prospective study show that, after controlling for age and comorbidity, illness perceptions were significantly related to the QLQ-C30 physical, role, emotional, cognitive, social functioning, and global health subscales. Patients with increased attention to symptoms, who believed in a greater likelihood of recurrence, who were more likely to engage in self-blame, and who had a stronger emotional reaction to the illness had lower QOL scores.

CONCLUSION

Our results suggest that restructuring negative pretreatment illness perceptions may help patients to cope more adequately during and after treatment.

Botulinum toxin type A for the treatment of chronic neck pain after neck dissection

BACKGROUND

Neck dissection surgery is often followed by chronic head and neck pain. To date optimal treatment of this type of pain is lacking. Botulinum toxin type A (BTX-A) has been shown to be effective in the treatment of myofascial pain syndrome and headache. In a pilot study, we wanted to test the effectiveness of BTX-A for the treatment of chronic neck pain after neck dissection.

METHODS

Sixteen patients with chronic neck pain after neck dissection were included in this prospective, open study. Eighty to 320 units of BTX-A (Dysport) were injected into muscular trigger points. Outcome measures included chronic pain and shooting pain on the basis of visual analog scales and quality of life improvement (EORTC QLQ-C-30; EORTC QLQ-H and N35) before and 4 weeks after treatment.

RESULTS

Patients showed a significant reduction in chronic pain (4.5 before to 3.3 after treatment, p =,005) and in shooting pain (6.1 before to 4.7 after treatment, p =.005). There was a trend toward improvement in global quality of life (QLQ-C30, p =.097) and an increase on the functional scale "pain" (QLQ-H and N35, p =.071).

CONCLUSIONS

BTX-A treatment of subjects with chronic neck pain after neck dissection resulted in a fast and significant reduction of pain. A significant improvement in quality of life may be expected in a longer time course after treatment.

The personality and quality of life in HNSCC patients following treatment

The aim of the present study was to investigate the association between self-reported quality of life (QoL) and personality in successfully treated primary head and neck squamous cell carcinoma (HNSCC) patients. We determined QoL using the European Organisation for Research and Treatment of Cancer Quality of life Questionnaire (EORTC-QLQ) C30/H and N35, and personality by the Eysenck Personality Inventory (EPI). All patients younger than 80 years who had been diagnosed with HNSCC in Western Norway in the period from 1992 to 1997, and who had survived until 1999, were sampled. 96 patients (a 90% response rate) were included. Questionnaires were also mailed to all Norwegian laryngectomised patients; 104 patients returned the questionnaires (a 50% response rate). The neuroticism scores were test re-test reliable as determined by the neuroticism scores measured at the primary HNSCC diagnosis for a sub-sample (N=22) of the included patients. High neuroticism was associated with a low QoL in both patient samples. The neuroticism score was associated with the QLQ-C30 scales (common variance: 17-25%) and all QoL scores in the laryngectomised group (common variance: 11-25%), and the H and N35 symptom scores in the laryngectomised sample. The associations could still be shown when adjustments were made for gender, age, marital status, educational level, number of children and level of treatment. Extraversion was associated with general QoL, physical and emotional scores in the HNSCC patient sample. Radiation therapy in the HNSCC sample was associated with the H and N35 symptom scores, but different ones to those associated with neuroticism. In conclusion, high neuroticism, but not extraversion, is associated with a lowered QoL.

Studies in the quality of life of head and neck cancer patients: results of a two-year longitudinal study and a comparative cross-sectional cross-cultural survey

OBJECTIVES

To examine quality-of-life (QL) changes that occur over time among patients treated for head and neck cancer and to compare QL outcomes in two geographically separate and culturally distinct populations.

STUDY DESIGN

A prospective, observational longitudinal study was made of QL changes over time in head and neck cancer patients, and a matched-pairs cross-sectional study was conducted for comparison of QL outcomes between groups of head and neck cancer patients from two different sociocultural environments.

METHODS

Patients attending a tertiary head and neck cancer center in Auckland, New Zealand, were interviewed using a validated questionnaire before treatment and at 3, 12, and 24 months after treatment. Changes over time were assessed according to gender, site and stage of primary tumor, and type of treatment received. A second group of patients from Toronto, Ontario, Canada, were matched to the first group for age, gender, site and stage of tumor, and time since treatment and interviewed using the same questionnaire. The group comparison was followed by a matched-pairs analysis for the 12-month follow-up interval.

RESULTS

In the longitudinal study, combined modality treatment resulted in greater physical and somatic dysfunction than single modality treatment. Patients learned to cope well with dysfunction and disability and with adjusting their lifestyle so that overall QL was not related to treatment received. Even so, pain scores and measures of psychological distress were related to overall QL. Otherwise there was no consistent correlation between specific symptoms and QL. An illustration of patients' adaptation to dysfunction was evident in scores for perceived difficulty swallowing, which decrease despite the ongoing need for a soft or liquid diet. In the comparative study, significantly different global QL scores were evident in the two clinical groups studied, despite similar social, somatic, and physical functioning. There was also a significant but inconstant difference in emotional functioning. Although the clinical groups received significantly different treatment regimens, the observed differences in global QL were independent of treatment received.

CONCLUSIONS

Patients with head and neck cancer generally managed well despite disability and dysfunction after treatment. Patients' expectations, emotional responses, and desired outcomes seemed to be determined by sociocultural factors, causing different patient groups to view their overall QL outcome somewhat differently.

Quality of life in patients of nasopharyngeal carcinoma: validation of the Taiwan Chinese version of the EORTC QLQ-C30 and the EORTC QLQ-H&N35

The authors followed the guidelines of translation and pilot testing of the EORTC QLQ-C30 and EORTC-QLQ-H&N35 questionnaires. The questionnaires were given to 50 nasopharyngeal carcinoma patients under active treatment and 50 under follow-up at our institution from November 2000 to June 2001. A retest was conducted 2 weeks after the first interview/form completion for the follow-up group. The intraclass correlation coefficients of the two questionnaires were moderate to high in the follow-up group. Cronbach's alpha coefficients of all scales of the two questionnaires were > or = 0.70 except that of cognitive functioning. Correlation of scales measuring similar dimensions of the QLQ-C30 and the SF-36 were moderate to high, while that of the QLQ-H&N35 and the QLQ-C30 and the SF-36 were moderate to low. Patients in the active treatment group had more serious acute problems due to disease and chemotherapy. Patients in the follow-up group had more serious chronic problems due to radiation therapy. We concluded that the Taiwan Chinese version of the EORTC QLQ-C30 and the EORTC QLQ-H&N35 had moderate to high test-retest reliability, high internal consistency in most scales, and could show the expected differences between patients in active treatment and follow-up group.

Quality of life in long-term survivors of oropharynx carcinoma

PURPOSE

To collect data on the health-related quality of life (QOL) of long-term survivors and to determine to what extent QOL might be an appropriate end point in the comparison of treatment options in oropharyngeal carcinoma.

METHODS AND MATERIALS

All patients treated between 1992 and 1998, in two French comprehensive cancer centers, by brachytherapy (BT) +/- external beam radiotherapy (EBRT) or surgery plus RT, or exclusive EBRT for T1-T3 (International Union Against Cancer staging system) oropharynx squamous cell carcinoma, were included. QOL was measured once in disease-free patients at least 2 years after treatment initiation. The European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire and the specific H&N35 module were self-administered by all participating patients. Sociodemographic data were collected using a questionnaire specifically designed for the study. The association between the QOL scores of the various treatment-, disease-, and patient-related variables was performed through bivariate analysis and then by multivariate analysis. The mean QOL scores of the EORTC QLQ-C30 questionnaire were compared with the mean scores in the general population.

RESULTS

Of the 159 eligible patients, 113 agreed to participate (97 men and 16 women, median age 61 years, range 41-83). The initial treatment was EBRT plus BT in 49 patients, surgery plus RT in 27, and EBRT alone in 37. The median follow-up time was 62 months (range 24-110). Compared with the general population, the three scores indicating the most impaired QOL were emotional and social functioning and fatigue. The clinical significance of global QOL impairment was borderline. The physical functioning, role functioning, and pain scores did not significantly differ from those of the general population. In multivariate analysis, the initial treatment had no significant influence on any dimension of QOL, except global QOL and emotional functioning. Surprisingly, surgery plus RT, as the initial treatment, favorably influenced the emotional functioning score and EBRT plus BT negatively influenced the global QOL score. None of these treatment modalities influenced any symptom scales. Patient selection was, at least partially, responsible for these paradoxical results.

CONCLUSION

The results of this study bring original and useful data about the QOL of long-term survivors of oropharynx carcinoma. In these patients, the QOL was significantly impaired, particularly in its psychosocial dimensions. The level of symptoms and functioning (except global QOL and emotional) was similar whatever the initial treatment. These results suggest the importance of coping processes. In a trial comparing treatment options from a long-term perspective, survival remains the most relevant end point, and a QOL evaluation should be a secondary end point. More prospective studies on QOL in head-and-neck cancer patients are needed to determine new strategies for rehabilitation management.

Alcohol consumption is associated with improved health-related quality of life in head and neck cancer patients

The study aim was to investigate the relationship between alcohol consumption and health-related quality of life (HRQL) in post-therapeutic head and neck cancer patients. A cross-sectional study design was used with a sample of 191 subjects. Data were collected through interview and chart review. Alcohol consumption was evaluated through the dichotomous response to the question "During the past month have you drunk alcohol on one or more occasions?" HRQL was evaluated through the EORTC QLQ-C30 and H&N35 instruments. Data were also collected concerning sociodemographic and clinical variables. Multivariate regression was used to evaluate the hypothesized association. Of 28 domains comprising the EORTC QLQ-C30 and H&N35 instruments, eight were significantly associated with alcohol consumption, while 19 of the 20 remaining domains showed a tendency towards an association. Alcohol drinking was associated with significantly better physical and role functioning, and better global HRQL, plus less fatigue, pain, problems swallowing, dry mouth and feelings of illness. This suggests that, while the study findings are limited by its design and the sample bias, despite alcohol's role as an aetiological factor, it may be reasonable to drink a little as one recovers from head and neck cancer.

Concomitant twice-a-day radiotherapy and chemotherapy in unresectable head and neck cancer patients: A long-term quality of life analysis

BACKGROUND

The purpose of this study is to make a comparative analysis between acute toxicity with late toxicity. This study is based upon a French quality of life (QoL) questionnaire in a cohort of advanced head and neck (H&N) cancer patients treated by concomitant twice-a-day continuous radiotherapy with no acceleration and chemotherapy with cisplatin and 5-fluorouracil.

METHODS

From September 1992 to November 1997, a prospective data bank of 91 patients was constituted. In November 1999, 31 patients were still alive and followed for more than 3 years. All patients had stage IV strictly unresectable squamous cell carcinoma of oropharynx or hypopharynx. A French specific H&N cancer QoL questionnaire was used at the end of radiotherapy and at the last date of follow-up of each patient (during 1999). p values reflect comparison of percentages obtained at the end of treatment with percentages at long-term follow-up. Statistical analysis was performed using chi(2) test (p <.05 considered as significant). Percentages obtained by the QoL questionnaire correspond to moderate-severe problems only.

RESULTS

Twenty-nine of 31 (94%) patients participated in the QoL study. Acute treatment toxicities were severe with declines in virtually all QoL and functional domains. Globally, with an average long-term follow-up of 4.5 years (range 3-7 years after treatment), there is a statistical improvement in the following symptoms: dry mouth and sticky saliva (97% versus 55%, p <.05); tasting problems (35% versus 21%, not significant); swallowing problems (77% versus 36%, p <.05); and H&N pain (86% versus 9%, p <.05). Financial problems were not improved (21% versus 14%, not significant), and psychological problems (59% versus 5%) were statistically significant. Fourteen of 29 (48%) patients were drinking and 8 of 29 (28%) were smoking at long-term follow-up; at the diagnosis they were 86% and 90%, respectively. At long-term follow-up 22 of 29 presented good or very good QoL, and 25 of 29 said they had improved their initial QoL.

CONCLUSION

The interest of twice-a-day radiotherapy with concomitant chemotherapy is to increase total radiotherapy equivalent dose without increasing late toxicity and also to improve locoregional control, survival, and long-term QoL/effectiveness ratio. Best supportive care is recommended to obtain both good QoL and cancer control in a long-term follow-up.