Prevalence of acute periapical abscesses in head and neck cancer patients receiving radiotherapy

AIMS

Head and neck cancer is a serious condition affecting the life of patients. Radiotherapy is commonly used to treat such conditions. The aim of this study was to assess the prevalence of acute periapical abscesses (PAs) in patients who received radiotherapy for head and neck cancer.

METHODS AND RESULTS

Data on acute PAs and oropharyngeal cancer (OPC) diagnosis with or without a history of radiation therapy (RAD) was retrieved by searching the appropriate query in the database. All cases were diagnosed for acute PAs by calibrated dentists for patients admitted to urgent care. The odds ratio (OR) for the prevalence of acute PAs and its association with a history of OPC with or without RAD were then calculated. Adjustment for comorbidities such as diabetes, smoking and gingival and periodontal diseases was also done. The prevalence of acute PAs in patients with a history of OPC was significantly higher as compared to the general hospital patient population (OR 2.92, 95%CI, p < .0001). Males were more affected than females and whites were more affected than African Americans and other ethnicities. The prevalence for PAs in patients with a history of OPC and RAD was higher and the difference in prevalence was statistically significant (OR 3.61, 95%CI, p < .0001). Whites were more affected than African Americans by more than 3.5-fold. Adjustment for diabetes comorbidly affected mainly the OPC + RAD group, however, the difference remained statistically significant. Adjustment for smoking and gingival and periodontal disease reduced the OR but the difference remained statistically different.

CONCLUSIONS

The high prevalence of acute PAs in patients with a history of OPC and RAD may suggest an association between these conditions warranting a meticulous medical and dental examination.

Myths, facts and scope of spinal cord tolerance dose revision in Intensity modulated SIB treatment of locally advanced head and neck cancer: A dosimetrical and radiobiological demonstration

PURPOSE

To explore the possibility of revising the spinal cord tolerance dose in Simultaneously Integrated Boost (SIB) intensity modulated treatment plan of locally advanced head and neck (H&N) cancer and assessment of achieved planning gain due to the revision. In SIB regimen, the Organ at Risk (OARs) tolerance dose is equally distributed throughout the treatment. Clinicians have usually considered the spinal cord tolerance to be the same as in conventional technique. However, in SIB fractionation regimen with intensity modulation treatment, the spinal cord may receive a physical dose of 45Gy, with much lesser dose per fraction than 2Gy per fraction. So when the dose of spinal cord is distributed throughout the treatment, the tolerance dose limit of physical dose can be considered higher than the usual conventional dose limits. In this study, an attempt has been made to explore the possibilities of dose escalation and treatment planning benefits while exploiting this "Window of Opportunity (WoO)" of increase in spinal cord and Planning Risk Volume (PRV) spinal cord tolerance dose.

MATERIAL AND METHODS

A total of 12 patients CT data set along with approved structure set of H&N cancer used for treatment planning in. Three independent SIB VMAT plans named as SPC, SPR and SPDE were generated for the 12 patients. First plan (SPC) was generated by considering standard spinal cord tissue constraint of maximum dose of 45Gy and PRV spinal cord maximum dose 50Gy as per QUANTEC summary and second plan (SPR) was generated considering spinal cord tissue constraint of maximum dose 52.50Gy and PRV spinal cord maximum dose 56.35Gy while optimization and dose calculation. The objectives for rest of the Organ at Risk (OAR) were kept same in both the plans during optimization and dose calculation. The SPC plan was copied for creation of third plan (SPDE) in which dose was escalated by increasing dose per fraction for target volumes such that dose to spinal cord reached a maximum dose of 52.50Gy and PRV spinal cord maximum dose of 56.35Gy. In this plan there have been changes to only dose per fraction, however dose optimization and dose calculation have not been performed. Radiobiological parameters TCP and NTCP were also calculated by using indigenously developed software.

RESULTS

Considering the increase of spinal cord tolerance dose as "window of opportunity", a sufficient escalation in physical dose, Biological Effective Dose (BED) and Tumor Control Probability (TCP) was observed for all target volumes with acceptable level of NTCP values.

CONCLUSION

Sufficient dose escalation and increased in TCP for target volumes or effective planning benefits can be achieved by revising the spinal cord tolerance dose in intensity modulated SIB treatment of locally advanced H&N cancers.

Chemoradiotherapy for advanced head and neck cancer - Analysis of a prospective, randomized trial

OBJECTIVE

To study the efficacy of neo-adjuvant chemotherapy followed by radiotherapy in advanced head and neck cancer.

STUDY DESIGN

Randomised, prospective study.

SETTING

Tertiary academic referral center.

PATIENTS

One hundred and eighty patients of advanced head and neck squamous cell carcinoma.

INTERVENTION

PATIENTS were randomized into two arms. The study arm (CT-RT arm) received 3 cycles of anterior chemotherapy with Inj. Cisplatin 100 mg/m(2) on D(1) and Inj 5F.U. 700 mg/m(2) on D(1)-D(4) at an interval of 21 days, followed by external radiation. The control arm (RT arm) received external radiotherapy only. The dose of Radiotherapy was 64 to 68 Gy in conventional fractionation.

RESULTS

PATIENTS of CT-RT showed better tumour control locally than patients who received only RT. Toxicities were commoner in CT-RT arm but they were manageable. 5 year survival is higher in the CT-RT arm (21% vs 16%; p value> 0.05).

CONCLUSION

Anterior chemotherapy with Cisplatin and 5F.U. is associated with good clinical response which is translated into increased survival along with acceptable toxicities.