Acute Hematologic and Mucosal Toxicities in Head and Neck Cancer Patients Undergoing Chemoradiotherapy: A Comparison of 3D-CRT, IMRT, and Helical Tomotherapy

Abstract

IMRT and helical tomotherapy for head and neck cancer (HNC) treatment are associated with higher doses to certain non-target tissues than traditional static beam techniques. We hypothesized that this may lead to higher acute mucosal and hematologic toxicities. This analysis was limited to 178 patients receiving ≥ 60 Gy with concurrent weekly cisplatin. Radiation delivery used 3D-CRT in 41 patients (23%), conventional IMRT in 56 patients (31%), and helical tomotherapy in 81 patients (46%). Acute mucositis rates, weekly hematologic parameters, and ability to deliver planned chemotherapy cycles were examined for each patient during their course of chemoradiotherapy. Analysis showed patients were well balanced with regard to sex, age, and stage. Treatment time, as assessed by delivered monitor units, varied significantly between the 3D-CRT (median=502), IMRT (median=1087), and tomotherapy (median=6757) cohorts. Acute mucositis grades did not significantly differ between the three subsets. Through six weeks of chemoradiotherapy, the median decline in hemoglobin was 15.6%, the median decline in platelets was 30.6%, and the median decline in leukocytes was 51.5%, but these drops were not significantly different between treatment cohorts. Chemotherapy was discontinued or held secondary to hematologic toxicity in 12% of 3D-CRT patients, 5% of IMRT patients and 15% of tomotherapy patients (p=0.14). In conclusion, HNC patients undergoing high dose radiation with concurrent weekly cisplatin chemotherapy, the longer beam-on times and larger volumes of low-to-moderate radiation doses to non-target tissues associated with modern IMRT delivery techniques do not appear to result in increased acute hematologic or mucosal toxicities.

Helical intensity‐modulated radiotherapy with concurrent chemotherapy for oropharyngeal squamous cell carcinoma: A prospective investigation of acute swallowing and toxicity patterns

“…However, key literature available for comparison has been outlined in Table 4, and data available suggests similarities between the current data and prior helical IMRT results. 35,37,38,45 Similarly, grade 2 rates also had substantial variation ranging from 30%-90% 38,45 with the current study results falling in the mid-range for both grades. 35,37,38,45 Similarly, grade 2 rates also had substantial variation ranging from 30%-90% 38,45 with the current study results falling in the mid-range for both grades.…”

“…Specifically, the low rate of long-term gastrostomy use (>12 months) was comparable to the rates reported by Nguyen et al 37 and Kimura et al 35 Oral mucositis data is the only other acute toxicity available for comparison, however, across the studies that have reported results, the incidence of grade 3 mucositis varies widely from 0%-72%. 35,37,38,45 Similarly, grade 2 rates also had substantial variation ranging from 30%-90% 38,45 with the current study results falling in the mid-range for both grades. Dysphagia outcomes have only been reported in 1 helical IMRT study to date.…”

“…[31][32][33] However, there are limited prospective studies directly comparing outcomes for the 2 techniques to allow definitive conclusions at this time. 6,7,10,14,15,45,[48][49][50] Overall, results indicate there is a pattern of improved outcomes in the current study, with the exception of dysphagia and xerostomia. Similarly, Chen et al 47 found no statistical difference in acute mucositis, dysphagia, and xerostomia rates between helical tomotherapy IMRT and a step-and-shoot IMRT in a study of 149 patients with mixed tumor sites.…”

“…[31][32][33] However, there are limited prospective studies directly comparing outcomes for the 2 techniques to allow definitive conclusions at this time. In 2013, Kruser et al 45 conducted a prospective study comparing conventional 3D CRT, linac-based IMRT, and helical tomotherapybased IMRT for 178 patients with mixed tumor sites receiving concurrent weekly cisplatin, and found no statistical difference in the rates of grade 2 and 3 mucositis or the rate of narcotic usage for the patients with oropharyngeal SCC. Similarly, Chen et al 47 found no statistical difference in acute mucositis, dysphagia, and xerostomia rates between helical tomotherapy IMRT and a step-and-shoot IMRT in a study of 149 patients with mixed tumor sites.…”

Oral mucosal injury in oncology patients: perspectives on maturation of a field

“…For example, high‐dose head and neck radiation typically causes mild injury in most patients when the oral mucosal tissue is exposed to at least 1500–2000 cGy; moderate‐to‐severe mucositis then predictably occurs as the radiation dose approaches and exceeds 5000 cGy. Intensity‐modulated radiation therapy (IMRT), although associated with higher doses to selected non‐target tissue vs static beam techniques, does not appear to cause increased acute mucosal toxicity (Kruser et al , ). High‐dose chemotherapy can cause oral mucositis ranging in severity from mild to severe, as is the case with gastrointestinal mucositis as well.…”