Influence of radiation dose to pharyngeal constrictor muscles on late dysphagia and quality of life in patients with locally advanced oropharyngeal carcinoma

BACKGROUND AND OBJECTIVE

Patients with oropharyngeal carcinoma (OPC) often have difficulty swallowing, which may affect quality of life (QoL). Radiation dose to constrictor muscles plays an important role.

METHODS

54 patients with locally advanced OPC were evaluated after intensity-modulated radiotherapy. Data were collected at standardized intervals using the EORTC questionnaires QLQ-C30 and QLQ-HN35 within two years. The pharyngeal constrictors (superior, middle, and inferior) were each contoured as an organ at risk. Influence of dose to the constrictors (≥55 Gy vs. <55 Gy) on late dysphagia and QoL was analyzed using the t‑test.

RESULTS

Late radiation-induced dysphagia depends significantly on the dose to the lower pharyngeal constrictor. At a dose of ≥55 Gy, 14 (64%) patients developed dysphagia grade ≤2 and 8 (36%) patients grade ≥3. At a dose of <55 Gy, the distribution at the end of radiotherapy (RT) was similar: 22 (69%) patients with dysphagia grade ≤2, 10 (31%) with grade ≥3. There was no dose-dependent difference in the severity of dysphagia in the acute phase (p = 0.989). There were differences 18 months after the end of RT: ≥55 Gy: 19 (86%) patients showed dysphagia grade ≤2; 3 (14%) grade ≥3. At <55 Gy, 31 (97%) patients developed grade ≤2, 1 (3%) grade ≥3 (18 months: p = 0.001; 24 months: p = 0.000). Late dysphagia is also dependent on the dose level of the middle constrictor muscle (6 months: p = 0.000; 12 months: p = 0.005, 18 months: p = 0.034). After 24 months, there was no significant difference (p = 0.374).

CONCLUSION

Radiation dose to the upper constrictor muscle appears to be of little relevance. The middle and lower constrictor should be given special consideration to avoid late dysphagia. Long-term QoL is independent on radiation dose.

Socioeconomic status and quality of life in patients with locally advanced head and neck cancer

PURPOSE

Socioeconomic aspects play an important role in health care. Patients with locally advanced head and neck cancer (LAHNC) experience detrimental effects on their quality of life (QoL). This prospective study examines QoL differences between patients with different socioeconomic status (SES) after intensity-modulated radiation therapy (IMRT).

PATIENTS AND METHODS

In all, 161 patients were questioned at the end of IMRT and at 12 and 24 months follow-up using the questionnaires of the European Organization for Research and Treatment of Cancer (EORTC) QLQ-30 and QLQ-HN35. Patients' QoL 2 years after IMRT was compared to a population reference sample and QoL of patients from lower, middle, and higher social class 2 years after IMRT was analyzed by ANCOVA using baseline QoL (end of radiation treatment) as a covariate.

RESULTS

Patients with high SES report worse QoL at the end of IMRT in the domains global health status (-15.2; p = 0.005), role function (-23.8; p = 0.002), and social function (-19.4; p = 0.023) compared to patients with middle and low SES. QoL improved during the first 12 and 24 months. However, 2 years after IMRT, middle and low SES patients report lower QoL in the domains global health status, physical function, and role function, and report a higher general (fatigue, pain, dyspnea) and head and neck cancer-specific symptom burden (pain, swallowing, senses, speech, social eating, opening mouth, and felt ill) than patients with high SES.

CONCLUSION

After IMRT for LAHNC, patients with high SES report worse QoL compared to patients with middle or low SES. There is a marked improvement within the first 24 months in many domains. However, the magnitude of improvement in patients with middle or low SES is significantly smaller compared to patients with high SES.

The current role of systemic chemotherapy in the primary treatment of head and neck cancer

The treatment of patients with locoregionally advanced squamous cell carcinoma of the head and neck (HNSCC) is still evolving into the perfect combination of the different multidisciplinary approaches. Induction chemotherapy (ICT) prior to planned definitive local therapy is widely used in this patient population for over 30 years but it is still unclear how to incorporate ICT into multimodality treatment the best. It appears to have a role in selected clinical situations especially for those patients with high risk for distant metastasis. However, since ICT protocols in different studies varies a lot, a comparative and consistent statement of benefits is difficult. We show the recent developments including randomized trials comparing radiochemotherapy (RCT) and ICT followed by definitive RCT here. This review summarizes how ICT has developed over the years, provides critical remarks of recent developments, and discusses how clinical trials including ICT should be conducted in the future.

[The most important study results of primary chemoradiation for head and neck squamous cell carcinoma : highlights of the ASCO Meeting 2013]

Primary concomitant and sequential chemoradiation is a commonly used therapeutic strategy for head and neck squamous cell carcinoma. At the annual meeting of the American Society of Clinical Oncology 2013 numerous trial results were presented. A selection of the most important trials will be summarized in this article. This year several results from phase II and III trials in concomitant and sequential therapy were demonstrated.

[Public awareness of human papilloma virus infection in the head and neck area: an appeal for precision in diagnostics and for public health awareness]

Infection with human papilloma virus (HPV) has been associated with head and neck carcinomas. Experts in HPV-positive carcinomas consider these carcinomas to be a new entity, because it has been shown that treatment outcome is excellent with significantly longer overall survival dependent of therapy. Despite this, in Germany public awareness of this development is rather low. A strategy for prophylactic vaccination against HPV-associated diseases has been available since 2007 but only to reduce the incidence of cervical cancer for girls between 12 and 17 years of age. There is an ongoing debate in Germany about the efficacy and safety of HPV vaccination. The results of epidemiological research in the USA which show that vaccination in young males is valuable are still not accepted in Germany. This article discusses the scientific and public awareness regarding this topic and calls for precision in diagnostics and public health awareness in order to establish a fertile ground for prevention and optimal treatment of HPV-associated diseases.

Xerostomia after radiotherapy. What matters--mean total dose or dose to each parotid gland?

PURPOSE

Xerostomia is a debilitating side effect of radiotherapy in patients with head and neck cancer. We undertook a prospective study of the effect on xerostomia and outcomes of sparing one or both parotid glands during radiotherapy for patients with squamous cell carcinoma of the head and neck.

METHODS AND MATERIALS

Patients with locally advanced squamous cell carcinoma of the head and neck received definitive (70 Gy in 2 Gy fractions) or adjuvant (60-66 Gy in 2 Gy fractions) curative-intent radiotherapy using helical tomotherapy with concurrent chemotherapy if appropriate. Group A received < 26 Gy to the left and right parotids and group B received < 26 Gy to either parotid.

RESULTS

The study included 126 patients; 114 (55 in group A and 59 in group B) had follow-up data. There were no statistically significant differences between groups in disease stage. Xerostomia was significantly reduced in group A vs. group B (p = 0.0381). Patients in group A also had significantly less dysphagia. Relapse-free and overall survival were not compromised in group A: 2-year relapse-free survival was 86% vs. 72% in group B (p = 0.361); 2-year overall survival was 88% and 76%, respectively (p = 0.251).

CONCLUSION

This analysis suggests that reducing radiotherapy doses to both parotid glands to < 26 Gy can reduce xerostomia and dysphagia significantly without compromising survival. Sparing both parotids while maintaining target volume coverage and clinical outcome should be the treatment goal and reporting radiotherapy doses delivered to the individual parotids should be standard practice.

[The most important results on primary chemoradiation for head and neck squamous cell carcinoma: highlights from the 2012 ASCO meeting]

Primary concomitant and sequential chemoradiation is a commonly used therapeutic strategy for head and neck squamous cell carcinoma. At the annual meeting of the 2012 American Society of Clinical Oncology numerous trial results were presented. A selection of the most important trials will be summarized in this article. This year, several important results from phase III trials-including the long awaited comparison of sequential and concomitant chemoradiation-were demonstrated.

Expression of insulin-like growth factor II mRNA-binding protein 3 in squamous cell carcinomas of the head and neck

BACKGROUND

Insulin-like growth factor II mRNA-binding protein 3 (IMP3) was found overexpressed in various cancer types suggesting its possible role in carcinogenesis. Analysis of IMP3 expression in head and neck squamous cell carcinomas (HNSCC) is rare so that we evaluated it using tissue microarray method.

METHOD

Immunohistochemical analysis of IMP3 was performed on samples from over 400 patients. The expression was measured semiquantitative, subsequently divided into four categories (negative, weak, medium, or strong) and correlated with several available clinicopathologic parameters.

RESULTS

For HNSCC, positive IMP3 expression was observed in patients with all tumor stages (pT1-4) and nodal stages (pN0-3), showing also significant statistical correlation (P=0.023 and P=0.0013, respectively). No further correlations were found. Separate analysis according to tumor localization (oral cavity, oropharyngeal, and laryngeal) showed a significant correlation of positive IMP3 expression and overall survival (P=0.038) only in patients with tumors of the oral cavity. Multivariate analysis showed IMP3 as an independent predictive marker for oral squamous cell carcinomas (OSCC).

CONCLUSION

Insulin-like growth factor II mRNA-binding protein 3 (IMP3) expression might be used as an independent prognostic factor in the subgroup of OSCC.

[Radiation therapy in head and neck cancer. Highlights from ASCO 2010]

In contrast to conventional radiotherapy, intensity modulated radiotherapy (IMRT) enables individually adjusted dose and intensity depending on tumor size and organs at risk, thus enabling radiotherapy of complex volumes in the head and neck area using high doses. Despite new data presented at the annual congress of the American Society of Clinical Oncology (ASCO), questions remain unanswered in two basic categories: (a) How do we use IMRT with other important advances in head and neck cancer treatment, such as altered fractionation, chemotherapy, and novel agents? (b) Does IMRT in its current form produce sufficient risk:benefit improvements in salivary gland sparing/less xerostomia, better targeting/local control and less late toxicity? Whether IMRT with its complex target volume definition and dose distribution leads to improved local control needs to be further investigated in relevant studies.

Human papilloma virus in locally advanced stage III/IV squamous cell cancer of the oropharynx and impact on choice of therapy

Oropharyngeal cancers (OPCs) are now believed to arise from two distinct pathways: one influenced by alcohol and tobacco use and the other a result of genomic instability induced by the human papilloma virus (HPV). The incidence of HPV-associated OPC is increasing, particularly among younger males. Case series and clinical trials suggest that patients with HPV-positive OPC have better clinical outcomes than those with HPV-negative tumors. We evaluated efficacy data in published articles and meeting abstracts from clinical studies comparing response rates and survival outcomes in patients with HPV-positive and -negative locally advanced OPC. Eight clinical studies were identified: half were prospective analyses of outcome according to HPV status; the remaining four reports were retrospective analyses. The majority of these analyses showed that patients with HPV-positive tumors had significantly better responses to treatment than those with HPV-negative tumors. In the two studies in which the effect of treatment was also evaluated, patients with HPV-positive tumors did not benefit significantly from intensive therapy, unlike those with HPV-negative tumors. HPV-positive tumor status is an important prognostic factor associated with a favorable outcome in patients with locally advanced OPC. The HPV status of patients with locally advanced OPC should be established before treatment commences. Surgery is well accepted in the treatment of OPC, but the place of chemoradiotherapy has yet to be confirmed. Prospective, well-controlled clinical studies are required to establish whether chemoradiotherapy provides an acceptable risk-benefit balance versus high-quality radiotherapy alone in patients with HPV-positive OPC, in whom the goal is to maximize progression-free and overall survival, while preserving function and maintaining quality of life.

ATM protein expression correlates with radioresistance in primary glioblastoma cells in culture

PURPOSE

Glioblastoma multiforme (GBM) is one of the malignancies most resistant to radiation therapy. In contrast, cells derived from individuals with ataxia telangiectasia (AT), possessing mutations in the ATM gene, demonstrate increased sensitivity to ionizing radiation. Using a collection of glioma specimens adapted to tissue culture and several established GBM cell lines, we investigated the relationship between ATM protein expression and radiosensitivity. The three aims of our study were to: (1) quantify ATM protein levels in cultured glioma cells; (2) measure the correlation between ATM protein levels and radiation sensitivity; and (3) examine the dependence of ATM on p53 status.

METHODS AND MATERIALS

Glioma specimens were collected, catalogued, and adapted to grow in culture. Levels of ATM, p53, and p21 proteins were determined by Western blot. Radiation sensitivities were determined by clonogenic assays. p53 mutation status was determined by DNA sequencing. Correlations were identified by linear regression analysis.

RESULTS

ATM protein levels were variable in the primary gliomas. Glioma cell lines demonstrated significantly lower levels of ATM protein. Clonogenic assays of cell strains and cell lines yielded survival fractions (SF2s) consistent with the radioresistant behavior of GBM tumors in vivo. Regression analysis revealed a high correlation between ATM protein levels and SF2 for primary glioma cell strains, but not for established GBM cell lines. p53 status failed to predict radiosensitivity.

CONCLUSION

We have demonstrated that while our collection of low passage cell cultures depends on ATM for their resistance to IR, established cell lines may acquire adaptive characteristics which downplay the role of the ATM gene product in vitro. Therefore, attenuating ATM gene expression may be a successful strategy in the treatment of GBM tumors.

Acetaminophen selectively reduces glioma cell growth and increases radiosensitivity in culture

Glioblastoma multiforme (GBM) is a highly lethal brain cancer. Using cultures of rodent and human malignant glioma cell lines, we demonstrated that millimolar concentrations of acetylsalicylate, acetaminophen, and ibuprofen all significantly reduce cell numbers after several days of culture. However, their mechanisms of action may vary, as demonstrated by (1) differences in the morphological changes produced by these compounds; (2) varied responses to these drugs with respect to toxicity kinetics; and (3) respective rates of cell proliferation, DNA synthesis, and mitotic index. We studied the effects of acetaminophen on relative cell number further. Evidence is presented that acetaminophen induced cell death by an apoptotic mechanism after a brief burst of mitosis in which cell numbers increased transiently, followed by a reduction in cell number and an increase in DNA fragmentation, as evidenced by terminal deoxytransferase-mediated dUTP-biotin nick end labeling (TUNEL) analysis. Using cultures of adult human brain and embryonic rat brain, we demonstrated that glioma cells were several-fold more sensitive to acetaminophen than normal brain cells in culture. Finally, subtoxic doses of acetaminophen increased the sensitivity of the human glioma cells in culture to ionizing radiation. Taken together, these results suggest that acetaminophen may prove to be a useful therapeutic agent in the treatment of human brain tumors.

Antisense ATM gene therapy: a strategy to increase the radiosensitivity of human tumors

Atm, the gene mutated in ataxia-telangiectasia (AT) patients, is an essential component of the signal transduction pathway that responds to DNA damage due to ionizing radiation (IR). We attenuated ATM protein expression in human glioblastoma cells by expressing antisense RNA to a functional domain of the atm gene. While ATM expression decreased, constitutive expression of p53 and p21 increased. Irradiated ATM-attenuated cells failed to induce p53, demonstrated radioresistant DNA synthesis, and increased radiosensitivity. Antisense-ATM gene therapy in conjunction with radiation therapy may provide a novel strategy for the treatment of cancer.