COVID-19: a simple statistical model for predicting intensive care unit load in exponential phases of the disease.

One major bottleneck in the ongoing COVID-19 pandemic is the limited number of critical care beds. Due to the dynamic development of infections and the time lag between when patients are infected and when a proportion of them enters an intensive care unit (ICU), the need for future intensive care can easily be underestimated. To infer future ICU load from reported infections, we suggest a simple statistical model that (1) accounts for time lags and (2) allows for making predictions depending on different future growth of infections. We have evaluated our model for three heavily affected regions in Europe, namely Berlin (Germany), Lombardy (Italy), and Madrid (Spain). Before extensive containment measures made an impact, we first estimate the region-specific model parameters, namely ICU rate, time lag between infection, and ICU admission as well as length of stay in ICU. Whereas for Berlin, an ICU rate of 6%, a time lag of 6 days, and a stay of 12 days in ICU provide the best fit of the data, for Lombardy and Madrid the ICU rate was higher (18% and 15%) and the time lag (0 and 3 days) and the stay in ICU (3 and 8 days) shorter. The region-specific models are then used to predict future ICU load assuming either a continued exponential phase with varying growth rates (0-15%) or linear growth. By keeping the growth rates flexible, this model allows for taking into account the potential effect of diverse containment measures. Thus, the model can help to predict a potential exceedance of ICU capacity depending on future growth. A sensitivity analysis for an extended time period shows that the proposed model is particularly useful for exponential phases of the disease.

Intensity modulated perioperative HDR brachytherapy for recurrent and/or advanced head and neck metastases.

Recurrent neck metastases following surgery and full dose adjuvant radiotherapy of squamous cell head and neck cancer remain a clinical challenge. After revision neck dissection and chemotherapy re-irradiation dosage is often limited and survival prognosis deteriorates. Here, adjuvant high-dose rate intensity modulated perioperative brachytherapy (HDR IMBT) offers a second full radiation dose with a limited volume of normal tissue radiation in the neck. In this retrospective study patients were identified who underwent revision surgery and perioperative HDR IMBT for recurrent neck metastases. Survival rates were estimated and the scarce literature on interstitial brachytherapy of the neck was reviewed. From 2006 to 2014, nine patients were treated for recurrent or palliative neck metastases using salvage surgery and HDR IMBT. Eight patients received previous surgery and external beam radiotherapy with or without chemotherapy. Two and five year overall survival was calculated to be 78 and 67 %, respectively. HDR IMBT is a salvage treatment option for selected cases in the neck following surgical revision or last-line treatment strategies. In the literature and this small cohort radiation toxicity and the risk of "carotid blow-out" seemed to be low.

Perioperative image-adapted brachytherapy for the treatment of paranasal sinus and nasal cavity malignancies.

PURPOSE: Sinonasal malignancies are a rare group of cancers often associated with late presentation and poor prognosis. In the past, there was little progress regarding survival rate, and often, multimodal treatment regimens are required. The aim of this study was to evaluate the clinical outcome of perioperative image-adapted brachytherapy (IABT) as part of a multidisciplinary treatment regimen for the therapy of sinonasal cancer. METHODS AND MATERIALS: Since 2006, patients with sinonasal cancer at the University Hospital of Schleswig-Holstein Campus Luebeck, Germany, were offered a multimodal treatment concept including head and neck surgery, perioperative IABT with or without external beam radiation therapy, and chemotherapy. In a retrospective study, such patients were analyzed for survival rate, tumor control, and toxicity of the interdisciplinary treatment. RESULTS: Thirty-five consecutive patients were analyzed. The majority of patients (63%) were treated for a primary tumor and 62% presented with tumor Stages III-IV. The mean follow-up time with IABT was 28 months. Overall survival estimate was 72% after 3 years. Disease-specific survival, disease-free survival, and local control rates were 83%, 63%, and 67%, respectively. On univariate analysis, a significant better disease-free survival rate was found in patients treated for primary, but not recurrent, sinonasal cancer (p = 0.006). The overall treatment toxicities were mainly classified Grade I. CONCLUSIONS: Interdisciplinary perioperative IABT is associated with excellent locoregional control and survival rates. IABT is well tolerated and shows low toxicity. Furthermore, visual acuity can be preserved in advanced cases. The implementation of perioperative IABT into multimodal treatment regimens improves the oncologic outcome.