Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616369
Title: Colorectal cancer survival in Jordan 2003-2007
Author: Al Nsour, Mohannad
ISNI:       0000 0004 5346 8782
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2014
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Abstract:
As in other less developed countries in the region and elsewhere, cancers are becoming a major cause of morbidity and mortality in Jordan. Globally, colorectal cancer (CRC) is the second most common cancer in women and the third most common cancer in men. In Jordan, CRC is the second most common cancer in women and the most common in men. There is little known about survival from CRC in Jordan and few survival studies have been conducted in comparable Eastern Mediterranean countries. As the first study of its type in Jordan, this thesis aimed at estimating CRC survival among Jordanian patients and comparing them with survival estimates among other populations. The thesis explored the relationship between CRC and socio-demographic characteristics, clinical manifestations, treatment, diabetes mellitus – for which the prevalence in Jordan is very high - and treatment sites. The study augmented existing Jordan Cancer Registry data by gathering additional case mix information and completing missing fields. CRC was classified according to international classification of oncology (ICD-O third edition in addition to the International Classification of Diseases, ICD-10) as C18.0-C20.9. The vital status of the patients was ascertained from Civil Registration Bureau based on use of the unique National Identification number of the patients with follow-up to 31 December, 2010. The survival duration of each case was determined as the time difference (in days) between the date of incidence (index date) and the date of death, date of loss to follow-up or the closing date for follow-up (31 December, 2010). Observed and relative CRC survival rates were calculated among a study population of 1,896 Jordanian colorectal patients aged 15 to 99 years of age, diagnosed with first invasive primary CRC from January 2003 to December 2007. The Kaplan-Meier method was used to determine the observed survival probability over time. The logrank test was used to estimate whether the difference in survival estimates was statistically significant between the groups. The complete approach of estimation of observed survival probability was used. Cox proportional hazard regression was used to assess the effect of each variable after simultaneously controlling the effects of potential confounders. With half of the sample aged 60 years and above, males were predominant (55.5 percent) with the majority of the sample (75.4 percent) residing in the central part of Jordan. The vast majority of the cases (63.5 percent) were diagnosed with colon cancer, with regional metastasis present in 58.9 percent. No significant difference was found in the distribution of colon and rectum cancer by sex. Adenocarcinoma was the most commonly found tumor (84.4 percent) compared to mucinous tumors which was found in 7.8 percent of the patients. In addition, 62.7 percent of the cases were classified as moderate and 14.9 percent as poor. The percentages of rectum cancer patients with moderate and poor/anaplastic types of cancer were higher than in colon cancer patients. The majority of patients (77.9 percent) underwent surgery, which was mostly elective (82.0 percent). A significantly higher occurrence of these elective surgeries was found among rectum cancer (87.7 percent) than colon cancer patients (78.7 percent). Curative treatment was found to be a more common form of treatment for colorectal cancer patients (76.5 percent) than palliative (23.5 percent). Of those undergoing surgery, 4.8 percent has died within 30-days of resection, with a significantly lower mortality among patients aged ≤ 65 years (2.9 percent) than the over 65 years age group (7.1 percent). Thirty days postoperative mortality was significantly higher among colon cancer patients (5.3 percent), patients with more advanced tumours and those who underwent emergency operations. Results of this study revealed that the incidence of CRC in the Jordanian population to be low compared to developed countries. However, this low incidence is similar to CRC incidence rates in other countries in the region. During the 5-year study period, the overall crude colorectal cancer incidence rate for males was 5.6 per 100,000 population, and 5.1 per 100,000 populations in females. The overall Age Standardized colorectal incidence rate (ASR) among males was 15.5 per 100,000 populations compared to 12.5 per 100,000 populations among females. For colon cancer, the crude incidence rate was 5.4 per 100,000 populations in males and 4.1 per 100 000 populations in females, while ASR for males was 11.1 and 8.4 for females. Alternatively, the crude incidence rate for rectum cancer was 3.0 per 100,000 population for males and 2.4 per 100,000 population for females, and the respective ASR incidence rates was 6.1 per 100,000 males and 4.9 per 100,000 females. Unexpectedly, results showed a high percentage (13.8 percent) of CRC patients among the young age groups (i.e. less than 40 years of age) with insignificant differences between the sexes. The age specific incidence rates were found to increase with age. The study revealed that 5-year observed and relative survival probabilities for colorectal cancer to be 57.7 and 61.3 percent respectively, with higher probability for colon cancer. These results showed good survival estimates of colorectal cancer compared to developed countries as well as the most developed countries in the region and across the Asian continent. The slightly higher observed colorectal survival rates among females were found to be insignificantly different than those for males. Patients aged 45 through 59 years had the highest survival estimates among all age groups, and the 75 years and above age group the lowest. The highest survival estimates were found among patients living in the central parts of Jordan, and the poorest was significantly noted in the south. Moreover, the observed and relative survival estimates were consistently highest during Year 1 and lowest during Year 5. Mucinous and serous tumors showed the poorest survival rates among the colorectal cancer, with higher 5-year relative survival rates among the mucinous and serous type of colon (52.4 percent) compared to rectum cancer (42.8 percent). With more than half of the colon patients (57.2 percent) and rectal patients (62 percent) having a regional spread; a higher proportion of colon cancers (24.1 percent) were found to have distant metastasis, than rectum cancer patients (20.5) and an equally low (11 percent) had localized CRC at diagnosis. Results also showed that observed and relative survival rates from localized and regional colon cancer were better than survival from rectum cancer in the same stages at 1, 3 and 5-years of diagnosis. Results also indicated that observed survival became poorer with increasing age for both localized and regional tumours. This observation was applicable for both males and females. In recognizing appropriate surgery as the most important aspect of colorectal cancer treatment, the observed survival probability for colorectal cancer patients who underwent surgery was found significantly higher than that for patients who did not undergo surgery. This scenario was similarly observed for both colon and rectum. Conversely, the overall relative survival rates for patients who underwent surgery declined from 96.2 percent to 62.6 percent between the first and fifth year and from 86.5 percent to 23.5 percent for patients who did not undergo surgery. In addition, no significant difference was found between colorectal survival estimates for patients who underwent elective surgery and those who underwent emergency surgery. This was held true for both colon and rectum cancer.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.616369  DOI: Not available
Keywords: R Medicine (General) ; RC0254 Neoplasms. Tumors. Oncology (including Cancer)
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