What else don't we know about the late effects of radiation in patients treated for head and neck cancer?

Factors influencing quality of life in patients during radiotherapy for head and neck cancer

INTRODUCTION

Radiotherapy (RT) in combination with chemotherapy is a standard of care for patients with head and neck squamous cell carcinoma (HNSCC). The RT is associated with side effects, which impact on quality of life (QoL). Thus, the aim of this prospective longitudinal study was to investigate the impact of RT on the QoL of patients with HNSCC during RT.

MATERIAL AND METHODS

From September 2008 to February 2010, 205 patients with locally advanced HNSCC were enrolled. The data pertaining to their QoL were collected using the EORTC QLQ-C30 and the EORTC Head and Neck Module (QLQ-H&N35) and then all items were transformed to a 0-100 scale according to the guidelines of the EORTC. The following clinical factors were chosen to study their potential influence on the QoL; site of primary, clinical stage, and methods of therapy: RT vs. chemoradiotherapy (CRT). Additionally, the sociodemographic factors (age, gender, education, habit of smoking) were studied.

RESULTS

Deterioration of almost all scales and items in the QLQ-C30 and QLQ-H&N35 questionnaire were noted at the end of RT. The following factors negatively influenced the QoL: age < 60 years (p < 0.05), female gender (p < 0.05), habit of smoking (p < 0.01), advanced clinical stage (III and IV) (p < 0.05), site of primary (larynx, hypopharynx) (p < 0.01), and CRT (p < 0.01).

CONCLUSIONS

Our study showed that RT significantly negatively influenced QoL at the end of the RT course. Additionally, this study demonstrated that age, gender, smoking habit, tumor site, and clinical stage of disease showed a significant effect on the QoL of HNSCC patients during RT.

Favourable impact of intensity-modulated radiation therapy on chronic dysphagia in patients with head and neck cancer

The aim of this study was to evaluate the impact of intensity-modulated radiation therapy (IMRT) on the incidence and severity of chronic dysphagia in patients with head and neck cancer. 62 evaluable patients with head and neck cancer who were treated with IMRT with or without concurrent chemotherapy were analysed. The majority of the patients (77.4%) had advanced locoregional disease. 45 patients underwent definitive IMRT and 17 received post-operative IMRT. Concurrent chemotherapy was given to 29 of the 45 patients treated with definitive IMRT. The average prescribed dose to clinical target volume (CTV)1 was 66-70 Gy (definitive IMRT) and 56-62 Gy (post-operative IMRT); 60 Gy to CTV2; 54 Gy to CTV3; and 50-52 Gy to the supraclavicular area. At a median follow-up of 19 months, 2-year actuarial locoregional control and survival was 77% and 74%, respectively. At 6 months after IMRT, chronic dysphagia was Grade 0 in 77.1% of patients, Grade 1 in 10.5% and Grade 2 in 12.3%. Acute mucositis showed no correlation with long-term dysphagia. The percutaneous endoscopic gastrostomy or nasogastric tube was removed in all of the patients within 8 weeks of completion of treatment. Xerostomia was Grade 0 in 61.4% of patients, Grade 1 in 31.5% and Grade 2 in 7% of patients. In conclusion, IMRT conferred a major favourable impact on chronic dysphagia in patients with locally advanced head and neck cancers, with satisfactory locoregional control.

Hypothyroidism might be related to breast cancer in post-menopausal women

An association between breast cancer and thyroid (autoimmune) diseases or the presence of thyroid peroxidase antibodies (TPOAb; a marker of thyroid autoimmune disease) has been suggested. However, little is known about whether women with thyroid (autoimmune) diseases are at increased risk for developing breast cancer. This cross-sectional and prospective cohort study investigated whether the presence of TPOAb or thyroid dysfunction is related to the presence or development of breast cancer. An unselected cohort of 2,775 women around menopause was screened for the thyroid parameters thyrotropin (TSH), free thyroxine (FT(4)), and TPOAb during 1994. Detailed information on previous or actual thyroid disorders and breast cancer, and on putative factors related to breast cancer and thyroid disorders, was obtained. Clinical thyroid dysfunction was defined by both abnormal FT4 and TSH, and subclinical thyroid dysfunction by abnormal TSH (with normal FT4). A TPOAb concentration >or= 100 U/ml was defined as positive (TPOAb(+)). The study group was linked with the Eindhoven Cancer Registry to detect all women with (in situ) breast cancer (ICD-O code 174) diagnosed between 1958 and 1994. Subsequently, in the prospective study, all women who did not have breast cancer in 1994 (n = 2,738) were followed up to July, 2003, and all new cases of (in situ) breast cancer and all cancer-related deaths were registered. Of the 2,775 women, 278 (10.0%) were TPOAb(+). At the 1994 screening, 37 women (1.3%) had breast cancer. TPOAbs were (independently) related to a current diagnosis of breast cancer (OR = 3.3; 95% CI 1.3-8.5). Of the remaining women, 61 (2.2%) developed breast cancer. New breast cancer was related to: (1) an earlier diagnosis of hypothyroidism (OR = 3.8; 95% CI 1.3-10.9); (2) the use of thyroid medication (OR = 3.2; 95% CI 1.0-10.7); and (3) low FT4 (lowest tenth percentile: OR = 2.3; 95% CI 1.2-4.6). In the first 3 years follow up, the relationship between FT4 and log-TSH was disturbed in women with a new breast cancer diagnosis. The presence of TPOAb was not related to breast cancer during follow-up. A direct relationship between thyroid autoimmunity and breast cancer is unlikely. Hypothyroidism and low-normal FT4 are related with an increased risk of breast cancer in post-menopausal women. Studies are needed to clarify the origins of this possible association.

Hypothyroïdie après irradiation cervicale dans le traitement des cancers du nasopharynx et du sein : étude prospective à propos de 84 patients

PURPOSE

1/ To evaluate the incidence of hypothyroidism following radiotherapy in the management of breast and nasopharyngeal carcinomas, 2/ to define the role of a systematic post therapeutic screening.

PATIENTS AND METHODS

From January 1996 through March 2001 a systematic evaluation of the clinical and the biological thyroid function was performed on a cohort of 84 patients that received supraclavicular irradiation. Selected patients had either a mammary (37 cases) or a nasopharyngeal (47 cases) carcinoma. Initial work up included thyroid inspection and palpation, and biological tests: serum FT4 and TSH levels, radioimmunochemistry, completed by dynamic thyroid stimulation, using TRH, in case of border line low T4 or isolated high TSH levels. Tests were repeated every three months the first year, and then every six months. Replacement therapy with L Thyroxin was administered in case of hypothyroidism.

RESULTS

All selected patients had a normal function initially. With a mean two years follow up (1-5 years), 24 patients (29%) experienced hypothyroidism, half of whom (13 cases) being purely biological. Five patients (11%), with a nasopharyngeal carcinoma, presented also with associated pituitary failure. Clinical symptoms were minor or mild in all cases. Hypothyroidism was detected at a mean 21 months follow up. In 2 patients, hypothyroidism disappeared spontaneously within 6 months. Possible predictive factors were evaluated: age of the time of radiation, gender, percentage of irradiated thyroid, total dose, dose per fraction, tumour type and chemotherapy. Only age appeared significantly correlated with thyroid dysfunction (range: 10-30 years, P=0.002).

CONCLUSION

Hypothyroidism is a frequent and certainly underestimated complication following radiotherapy of the neck. In such patients, a systematic clinical and biological evaluation every three months the first year, and then every six months until five years is recommended.

Evaluations of quality of life and organ function

For advanced head and neck cancer (HNC) patients, aggressive radiation and chemoradiation treatments offer new therapy options. The aims of these regimens are increased survival and organ preservation, with the goals of preserving organ function, minimizing late effects, and improving quality of life (QOL). At the same time, the toxicities of these regimens are acknowledged as is the potential for long-term dysfunction. Thus, particularly now, with the increasing use of aggressive chemoradiation therapy (CRT) regimens, documentation of the QOL and functional outcomes of these treatments is critical. The implications for speech and swallowing are widely recognized and the broader effects of these impairments on overall QOL have received some attention. This article presents data on the performance, functional, and QOL results of radiation therapy (RT) and various CRT regimens in HNC.

Radiotherapy-induced thyroid disorders

Despite their specific functional consequences, radiotherapy-induced thyroid abnormalities remain under-estimated and underreported. These sequelae may include primary or central hypothyroidism, thyroiditis, Graves' disease, euthyroid Graves' ophthalmopathy, benign adenomas, multinodular goitre and radiation-induced thyroid carcinoma. Primary hypothyroidism, the most common radiation-induced thyroid dysfunction, affects 20-30% of patients administered following curative radiotherapy to the neck region, with approximately half of the events occurring within the first 5 years after therapy. The relative risk of radiation-induced cancer (mainly well-differentiated tumours) is 15-53-fold higher than in non-irradiated population. The aetiology of radiation-induced thyroid injury includes vascular damage, parenchymal cell damage and auto-immune reactions. Total radiotherapy dose, irradiated volume of the thyroid gland, and the extent of prior thyroid resection are among the most important factors associated with the risk of hypothyroidism. The contribution of other treatment modalities (chemotherapy, endocrine therapy) as well as patient- and tumour-related factors is less clear. Reduction in radiation dose to the thyroid gland and hypothalamic/pituitary complex should be attempted whenever possible. New radiotherapy techniques, such as stereotactic radiosurgery, three-dimensional conformal irradiation, intensity modulated radiotherapy and proton therapy allow generally better dose distribution with lower dose to the non-target organs. The diagnostic approach to thyroid radiation injury includes baseline thyroid function assays in all patients undergoing thyroid or parasellar irradiation. Recommended follow-up procedures include at least annual evaluation with a history for symptoms of thyroid dysfunction, clinical examination, and measurement of thyroid hormones and thyrotropin. Management of overt hypothyroidism is based on hormone replacement therapy. Thyroid hormone therapy is also recommended in cases of subclinical hypothyroidism. Treatment of other radiation-induced thyroid disorders (thyroiditis, Graves' disease, thyroid cancer) is similar to that employed in spontaneously occurring conditions. Further improvements in radiotherapy techniques and progress in endocrine diagnostics and therapy may allow better prevention and management of radiation-related thyroid injury.

[Post-radiotherapy hyperthyroidism: a rare complication of cancer treatment in the child]

Abnormalities of thyroid function, specially hypothyroidism, are common complications of head and neck irradiation for childhood cancer. Hyperthyroidism is rare and can be misdiagnosed. We report two observations of this condition.

OBSERVATIONS

The first patient received conventional craniospinal irradiation for a localized medulloblastoma. Three years later, he presented with profuse sweating, irritability and paroxysmal tachycardia. Biologic evaluation revealed a peripheral hyperthyroidism. The patient was treated with antithyroidian hormonal treatment. The second patient received an irradiation for an undifferentiated nasopharyngeal carcinoma. Three years later, she developed a progressive thyrotoxicosis which was attributed to hyperthyroidism after six months of evolution. Hormonal treatment improved the clinical state after several weeks.

CONCLUSION

Hyperthyroidism is a rare complication of head and neck irradiation. This condition justifies a periodic and prolonged evaluation of thyroid function.

Hypothyroidism: a frequent event after radiotherapy and after radiotherapy with chemotherapy for patients with head and neck carcinoma

BACKGROUND

The incidence of hypothyroidism was assessed retrospectively from a data base of 155 patients with head and neck carcinoma who were treated at the Cleveland Clinic Foundation between 1990 and 1997.

METHODS

One hundred patients were randomized between radiotherapy (RT) (66-72 grays in single daily fractions) and RT with concurrent chemotherapy (CT) using 5-fluorouracil and cisplatin. An additional 55 patients received RT and CT without randomization. Primary site surgery was performed for tumor persistence or recurrence and included a thyroidectomy in nine patients. These nine patients, along with three patients who had hypothyroidism prior to treatment, were excluded from the analysis. At regular intervals after the completion of treatment, all patients were evaluated for the development of hypothyroidism, defined as a serum thyroid-stimulating hormone (TSH) level > 5.5 microU/mL.

RESULTS

With a median follow-up for 143 evaluable patients of 4.4 years (range, 1.5-9.2 years), the 5-year Kaplan-Meier projected incidence rate of hypothyroidism was 48%, and the 8-year projected incidence rate was 67%. The median time to the development of hypothyroidism was 1.4 years (range, 0.3-7.2 years). The likelihood of developing hypothyroidism could not be predicted according to age, gender, primary site, tumor or lymph node status, overall stage, RT dosage to the primary site or to the neck, or inclusion of CT in the treatment plan. Only race proved predictive, with no African-American patients developing hypothyroidism (P = 0.02).

CONCLUSIONS

The authors conclude that the incidence rate of hypothyroidism after patients undergo RT for head and neck carcinoma is higher than generally reported and that TSH screening after treatment appears justified.

T classification and clivus margin as risk factors for determining locoregional control by radiotherapy of nasopharyngeal carcinoma

BACKGROUND

The purpose of this study was to determine risk factors that affect locoregional control of nasopharyngeal carcinoma (NPC) after radiotherapy. Computed tomography (CT) is utilized for radiotherapy planning and for identifying high risk anatomic areas.

METHODS

Between April 1990 and December 1993, 40 consecutive patients (1 in Stage I, 3 in Stage II, 5 in Stage III, and 31 in Stage IV) who had locoregional NPC were given definitive radiotherapy at the Koo Foundation Sun Yat-Sen Cancer Center in Taipei, Taiwan. All patients had individualized CT treatment planning. The dimension of each tumor as shown on the treatment planning CT were mapped on conventional simulation films. The extent of each tumor was further affirmed by magnetic resonance imaging (MRI) and the tumor map revised as necessary. The primary radiation fields were designed to include the primary tumor and potential spread areas with appropriate margins. Concurrent chemotherapy was also given to 35 patients (87.5%) who had positive cervical lymph nodes or primary tumors extending beyond the nasopharynx.

RESULTS

By the end of December 1995, after a median follow-up of 42 months and minimal follow-up of 24 months, the locoregional control rate at 4 years was 84.8% (95% confidence interval [CI], 72.3-97.3), disease free survival 68.4% (95% CI, 52. 1-84.7), and overall survival 76.7% (95% CI, 63.4-90.0). The radiation field margin near the sphenoid sinus averaged 1.9 cm, the clivus margin 1.1 cm, the pterygoid fossa margin 2.0 cm, and the oral cavity margin 1.7 cm. Risk factor analysis revealed that T classification and the radiation field margin at the clivus were the most important factors for locoregional control of the tumor. The locoregional control rates were 92.6% (25/27) for T1-T3 patients and 76.9% (10/13) for T4 patients (P = 0.03). The locoregional control rates were 71.4% (5/7) for patients with a clivus margin < 1 cm and 90.6% (29/32) for patients with a clivus margin > or = 1 cm (P = 0.08).

CONCLUSIONS

The excellent locoregional control observed in this series may be attributed to the concurrent chemotherapy and radiotherapy as well as meticulous treatment planning with CT and MRI. The precise delineation of the involved area with the aid of CT, which is taken while the patient is in the position for irradiation, serves to define the necessary safety margin of the radiation field. T classification and clivus margin are the most important factors in determining locoregional control of radiotherapy of NPC. The statistical trend observed in this study indicated that the clivus margin should be adequate to reduce the failure around the clivus, as all local recurrences were observed in this area.

Hypothyroidism after external radiotherapy for head and neck cancer

PURPOSE

To study the development of thyroid hypofunction in patients with head and neck cancers admitted for external radiotherapy.

METHODS AND MATERIALS

Between November 1990 and July 1996, thyroid function was measured in 264 consecutive patients, where the entire thyroid gland or part of it was included in the target volume. The time to development of hypothyroidism (HT) was calculated from the start of the radiotherapy.

RESULTS

The median follow-up period was 19 months. Seventeen patients (6%) developed elevated serum thyroid-stimulating hormone levels with depressed (free) thyroxine levels (i.e., clinical HT). Elevated serum thyroid-stimulating hormone level with normal (free) thyroxine levels (i.e., chemical HT) developed in 57 (22%). The median time to clinical HT was 15 months (range: 7 to 32). The median time to chemical HT was also 15 months (range: 2 to 28). The actuarial risk of developing clinical or chemical HT 3 years after treatment was 15 and 40%, respectively. The incidence of chemical HT was significantly higher (p = 0.041) when the whole thyroid was included in the target volume compared to patients where only part of the thyroid was irradiated. The same trend was seen as regards clinical HT (p = 0.063). For those 20 patients who underwent laryngectomy, there was an increased risk of both chemical and clinical HT (p = 0.011 and 0.019, respectively). Increasing age was associated with an increased risk of chemical HT (p = 0.001), but not of clinical HT (p = 0.553). Sex, tumor site, radiation dose, and combination of radiotherapy and chemotherapy were not significant factors for thyroid hypofunction.

CONCLUSION

Depressed thyroid function is common after external radiotherapy for cancers of the head and neck. Routine testing for possible thyroid hypofunction should be included in the follow-up procedures, even many years after end of radiotherapy.