Novel oral cancer survival calculator includes comorbidities to offer more accurate estimates

14th July 2023

A personalised oral cancer survival calculator has been found to provide a more accurate prediction of survival or mortality through the incorporation of a patient’s comorbidities.

The recently developed Oral Cancer Survival Calculator uses a novel modelling approach that gives an equal weight to the risk of death from other causes and gives a better estimate of survival in those with oral cancers.

Once an individual receives a cancer diagnosis, this becomes a focus as their main threat to survival. But the researchers sought to determine how the competing risk of death from noncancer causes affects the risk of death from oral cancer. In other words, do patients with oral cancer have a higher risk of death from other causes?

Oral cancer was selected to develop the model as the cancer develops over time and co-morbidities are an important feature.

In the study, published in the journal JAMA Otolaryngology Head and Neck Surgery, the researchers set out to design a statistical framework and accompanying Oral Cancer Survival Calculator, which factored in other pre-existing conditions, to provide personalised estimates of the probability of a patient surviving or dying from cancer or other causes. 

The team used cancer data from the SEER database, SEER-Medicare linked files for co-morbidity information and the National Health Interview Survey (NHIS) – the principal source of information on the health of the civilian population in the US. 

Using this data, researchers developed statistical methods to calculate natural life expectancy in the absence of the cancer, cancer-specific survival and other-cause survival. This was then applied to the oral cancer data. The main outcome of interest were the probabilities of surviving or dying from oral cancer or from other causes, and life expectancy in the absence of the cancer.

Oral cancer data model

A total of 22,392 patients with oral squamous cell carcinoma (60.5% male) and 402,626 NHIS interviewees were included. The calculator was specifically designed for use in patients aged between 20 and 86 years, with newly diagnosed oral cancer.

Using the model, researchers estimated that conditional on having survived to age 50 year, a female and male patient diagnosed with stage III cancer would have a 60% and 44% chance, respectively, of being alive at age 70 years, in the absence of their cancer.

For comparative purposes, in the general US population, the corresponding estimates are 86% and 79%, respectively – an absolute difference of 26 and 35 percentage points, respectively.

Taken together, the overall findings suggested that patients with oral cancer have a greater risk of dying of other causes than a matched US population due to the number and type of comorbidities. In fact, even after adjustment for co-morbidities, their likelihood of dying of other causes increases as their cancer stage increases.

The researchers also highlighted that survival estimates that exclude the effects of coexisting conditions can lead to under- or overestimates of survival.

This new tool provides personalised data for discussions between clinicians and patients about the place of cancer treatment in the patient’s life as a whole. It will be broadly applicable for developing future prognostic models of cancer and noncancer aspects of a person’s health in other cancers, they concluded.

Combining respiratory SOFA and burn area score predict mortality in severe burn and inhalation injury

13th January 2023

A high respiratory SOFA (Sequential Organ Failure Assessment) score combined in a predictive model with the total body surface area burned (TBSA), was the best predictor of mortality risk in patients with severe burns and inhalation injury, according to a study by Chinese researchers.

Patients with severe burns and inhalation injury are at an increased risk of infection, longer hospital stays and death. In fact, the presence of smoke inhalation injury with a cutaneous burn significantly increases morbidity and mortality.

Assessment of burns can be undertaken using the Baux score, which is the summation of the patient’s age and the percentage of total body surface area (%TBSA) burned and is often quoted as the estimated percentage risk of death.

However, a revised Baux score includes inhalation injury and is simple enough for mental calculation.

The respiratory SOFA score is based on the PaO₂/FiO₂ (PF) ratio and ranges from 0 to 4 points, where higher scores indicate worsening respiratory dysfunction.

The PF ratio has also been shown to be highly correlated with smoke inhalation injury in burned children. 

Despite this, to date, there is a lack of data on the value of the respiratory SOFA score in the prognosis of severe burn patients with inhalation injury.

For the present study, the Chinese team speculated that the respiratory SOFA score might be an important prognostic factor in such patients and undertook a retrospective analysis to determine the relevance of the score in the survival of severe burn patients with inhalation injury.

The study included adult burn patients with inhalation injury and where the burn area was greater than 20%. Multivariate Cox’s regression analysis was used to identify significant predictors of death and the sensitivity, specificity, and accuracy of the area under the ROC curve calculated.

Respiratory SOFA and survival analysis

The retrospective analysis included 118 patients with a mean age of 45.9 years (23.7% female) and of whom, 74.6% had experienced a flame burn, with a mean TBSA of 56.4%.

Univariate analysis revealed that both a large-area TBSA and a respiratory SOFA score of 3 – 4, increased the risk of death. In fact, TBSA (Hazard ratio, HR = 2.38, 95% CI 1.49 –3.79, p < 0.001) and the respiratory SOFA score (HR  =  3.12, 95% CI 1.90 – 5.19, p < 0.001) were both independently associated with a shorter time to death.

In ROC curve analysis, a model incorporating TBSA and the respiratory SOFA score had an area under the curve, AUC, of 0.96 compared to the revised Baux score model (AUC = 0.93) for prediction of mortality and this difference was non-significant (p  =  0.18).

In addition, the TBSA and the respiratory SOFA score model had a sensitivity of 0.95 and a specificity of 0.85.

The authors concluded that combining the TBSA and the respiratory SOFA score, improves the predictive level for patients with inhalation burns.

Citation
Ji Q et al. Survival and analysis of prognostic factors for severe burn patients with inhalation injury: based on the respiratory SOFA score. BMC Emerg Med 2023.