Clinical and radiobiological consideration of cyclical hypofractionated radiation therapy also known as QUAD Shot for neglected skin cancer disfiguring the face of a non-compliant patient who was refusing surgery and protracted radiation therapy: case report

The efficacy of radiation therapy using the Quad Shot regimen in cutaneous metastasis from parotid gland cancer: A case report

Cutaneous metastasis from malignant tumors can cause symptoms such as exudates, bleeding, and pain, which remarkably reduce patient's quality of life. Herein, we report a case in which radiation therapy using the Quad Shot regimen was effective in the treatment of cutaneous metastasis from parotid gland cancer.

Use of a cyclical hypofractionated radiotherapy regime ('QUAD shot') for the treatment of feline sinonasal carcinomas

OBJECTIVES

Radiation therapy is the treatment of choice for cats with sinonasal carcinomas. Different protocols have been described in the literature, though a clear consensus regarding the optimal protocol is lacking. The aim of the study was to describe the tolerability, efficacy and outcome of cats treated with a cyclical hypofractionated protocol.

METHODS

Cats with histologically diagnosed sinonasal carcinomas in a single institution were retrospectively included. All patients were treated with a cyclical hypofractionated protocol ('QUAD shot' regime). Cats were treated with 4 Gray (Gy) delivered in four fractions within 48 h, with a minimum of 6 h between two treatments, and repeated every 3-4 weeks for a total dose of 48 Gy in three cycles.

RESULTS

Seven cats met the inclusion criteria. Nasal discharge and sneezing were the most common presenting complaints. All cats presented with advanced stage of disease with CT examination (three with modified Adams stage 3 and four with stage 4). Clinical improvement was seen in six cats. Five cats had a follow-up CT; one had a complete response, two had partial responses, one had stable disease and one had progressive disease. Two cats were still alive at the time of writing while four were euthanased owing to tumour-related causes. The median overall survival time was 460 days. The 1-year survival time was 80% and the 2-year survival time was 0%. Severe acute or late toxicity was not reported.

CONCLUSIONS AND RELEVANCE

This is the first report of a cyclical hypofractionated protocol in the veterinary literature that can provide prolonged survival in cats with advanced stage sinonasal carcinoma. Its use should be considered in patients when prolonged hospitalisation can be detrimental to quality of life, while still delivering a therapeutic total dose of radiation therapy.

Rapid and Durable Symptom Palliation With Quad Shot Radiation Therapy to Nonosseous Metastatic/Recurrent Cancer in Elderly or Frail Patients in a Rural Community Clinic

More than half of patients with cancer receiving radiation therapy (RT) are treated in a palliative setting. Elderly or frail patients with metastatic/recurrent cancer require palliative RT that can provide a rapid cancer-related symptom response with low toxicity and short overall treatment time. Cyclical hypofractionated RT (quad shot: 14-14.8 Gy/4 fractions, twice-daily treatments with 6-hour intervals on 2 consecutive days monthly to a total of 42-44.4 Gy) can be a practical palliative RT regimen for patients with poor performance status. In this report, we present palliative symptom response and objective tumor response after quad shot for elderly or frail patients with nonosseous metastatic/recurrent cancers in various sites with varying histology.

Proton radiotherapy for recurrent or metastatic sarcoma with palliative quad shot

Patients with previously treated, recurrent or metastatic sarcomas who have progressed on multiples lines of systemic therapy may have limited options for local control. We evaluated outcomes of palliative proton therapy with the quad shot regimen to unresectable disease for patients with recurrent and/or metastatic sarcoma. From 2014 to 2018, 28 patients with recurrent or metastatic sarcomas were treated to 40 total sites with palliative proton RT with quad shot (14.8 Gy/4 twice daily). Outcomes included toxicity, ability to receive further systemic therapy, and subjective palliative response. Univariate analysis was performed for local progression‐free survival (LPFS) and overall survival (OS). Of the 40 total sites, 25 (62.5%) received ≥3 cycles with median follow up of 12 months (IQR 4–19). The most common histologies were GIST (9; 22.5%) and leiomyosarcoma (7; 17.5%). A total of 27 (67.5%) sites were located in the abdomen or pelvis. Seventeen (42.5%) treatments involved concurrent systemic therapy and 13 (32.5%) patients received further systemic therapy following proton therapy. Overall subjective palliative response was 70%. Median LPFS was 11 months and 6‐month LPFS was 66.1%. On univariate analysis, receipt of four cycles of quad shot (HR 0.06, p = 0.02) and receipt of systemic therapy after completion of radiation therapy (HR 0.17, p = 0.02) were associated with improved LPFS. Three grade 3 acute toxicities were observed. The proton quad shot regimen serves as a feasible alternative for patients with previously treated, recurrent or metastatic sarcomas where overall treatment options may be limited.

The Role of Postoperative Radiotherapy and Prognostic Model in Primary Squamous Cell Carcinoma of Parotid Gland

Background

Primary squamous cell carcinoma of parotid gland (parotid SCC) is a high malignant histologic subtype of parotid cancers with aggressive clinical presentation. However, the clinical features and survival benefit of postoperative radiotherapy (PORT) for primary parotid SCC are not well known.

Methods

A retrospective population-based study was performed to identify the role of PORT in parotid SCC patients diagnosed between 1975 and 2016 from SEER database. A prognostic risk model was established based on patient clinical features, including age, tumor stage, and node involvement status. Patients were stratified into high, intermediate, and low risk according to this model. The survival benefit of radiotherapy was compared in the whole cohort and different risk groups.

Results

Nine hundred thirty-one parotid SCC patients were extracted from SEER database, 634 (68.1%) in the RT group and 286 (30.7%) in the non-RT group. Overall, 503 (54.0%) deaths occurred, with a median follow-up of 84 months, the 5-year OS was 43.6% in the whole cohort, 47.7 vs 35.9% in patients with/without PORT (P = 0.005), and 58.9 vs. 38.8 vs. 27.1% in low-, intermediate-, and high-risk group (P < 0.001). Compared with surgery alone, PORT significantly improved the OS of patients with medium risk (47.5 vs. 20.6, P < 0.001), whereas not in the low risk (61 vs. 54%, P = 0.710) and high (25.6 vs. 28.7%, P = 0.524).

Conclusion

This prognostic model can separate the patients with parotid squamous cell carcinoma into different risk. PORT significantly improved the OS of patients with intermediate risk, whereas high-risk group may need more intensive treatment strategies.