Relationship among age, race, medical funding, and cervical cancer survival

Application of Mixture Cure Models in Determining the Survival of Patients with Cervical Cancer

Background: Cervical cancer is the fourth most common cancer among women and the seventh most common worldwide. Objectives: The present study aimed at investigating the usability of cure models in analyzing patients' survival. Besides, the factors affecting the long-term and short-term survival of the patients were determined, using Weibull, log-logistic, and log-normal models. Methods: The sample population of the study included 109 female patients with cervical cancer referred to Motahhari Hospital of Urmia (West Azerbaijan province) from 2004 to 2015. The cure survival analysis was used to determine the patients' survival. Results: The mean and standard deviation age at diagnosis was 50.1 ± 11.7 years. The patients' age, age at marriage, and the disease relapse were significant in the single-variable model on the long-term survival function of the patients. Moreover, the findings showed that Cured Log Logistic Parametric Model was more suitable for analyzing survival data in West Azerbaijan Province, Iran. The relapse variable was significant for all the parametric models. Conclusions: Given the divided sample population into immune and susceptible groups, the mixture cure models can be used to analyze the long-term and short-term survival of the patients with cervical cancer. Moreover, these models can be used to recognize the factors affecting both groups simultaneously.

Ten Years’ Survival in Patients with Cervical Cancer and Related Factors in West Azerbaijan Province: Using of Cox Proportion Hazard Model

Objective: There are two basic ways to analyze survival data including nonparametric and parametric methods. Considering that cervical cancer is the fourth most common cancer among women, this study was conducted using a suitable regression model for survival data for patients with cervical cancer in Urmia. Material and Methods: In this historical retrospective study, all patients with cervical cancer who referred to Motahhari Hospital of Urmia during 2004 and 2015 were included in the study and consisted of 109 women with cervical cancer. The data were collected using checklist which filled with records of patients. The data were described with percent, mean and standard deviation. The survival function was computed with the Kaplan-Meier method. The adjusted Hazard Ratio for variables were estimated after fitting the Cox proportion hazard model using Forward Stepwise Likelihood Ratio method with PE=0.1, PR=0.15. Results: Of the 109 patients, the mean (SD) time of diagnosis was 50.1% (11.7) years. The mean (SD) and median of follow-up time was 38.23 (32.50) and 27.1 months (Mim:2 months and Max:132 months). Ninty-Three of patients (88.7%) were in urban area. Using Log-Rank test, the mean score of survival in patients with recurrence of 38.8 months was significantly lower than those without recurrence (102.5 months) (P <0.001). The results of the COX model showed that the adjusted relative risk of mortality with a diagnostic age of 50 years or more compared to those under 50 years of age was 1.978. The risk for marriage under age 20 was 3.189 compared to the marriage age of 20 years or more. Conclusion: According to results, the low age of marriage increases the occurrence of advanced stages of cancer in older ages and as a social and cultural factor has a significant effect on the survival of patients with cervical cancer.

Differences in vitamin D status may account for unexplained disparities in cancer survival rates between African and white Americans

Considerable disparities in cancer survival rates exist between African Americans (AAs) and white Americans (WAs). Various factors such as differences in socioeconomic status (SES), cancer stage at time of diagnosis, and treatment—which this analysis considers primary explanatory factors—have accounted for many of these differences. An additional factor not usually considered is vitamin D. Previous studies have inversely correlated higher solar ultraviolet-B (UVB) doses and serum 25-hydroxyvitamin D (25(OH)D) concentrations with incidence and/or mortality rates for about 20 types of cancer and improved survival rates for eight types of cancer. Because of darker skin pigmentation, AAs have 40% lower serum 25(OH)D concentrations than WAs. This study reviews the literature on disparities in cancer survival between AAs and WAs. The journal literature indicates that there are disparities for 13 types of cancer after consideration of SES, stage at diagnosis and treatment: bladder, breast, colon, endometrial, lung, ovarian, pancreatic, prostate, rectal, testicular, and vaginal cancer; Hodgkin lymphoma and melanoma. Solar UVB doses and/or serum 25(OH)D concentrations have been reported inversely correlated with incidence and/or mortality rates for all of these cancers. This finding suggests that future studies should consider serum 25(OH)D concentrations in addressing cancer survival disparities through both measurements of serum 25(OH)D concentrations and increasing serum 25(OH)D concentrations of those diagnosed with cancer, leading to improved survival rates and reduced disparities.