Tumor size as measured at initial X-ray examination, not length of bile duct stricture, predicts survival in patients with unresectable pancreatic cancer

Abstract

BackgroundThe survival of unresectable pancreatic cancer patients is extremely poor. The aim of this study was to examine if tumor size could predict survival length in order to optimize patient care.MethodsA retrospective observational study was performed on 185 consecutive patients with unresectable pancreatic cancer (ICD10: C250-2 and C258) who were diagnosed from 2003 to May 2010. The patients' initial radiographs at presentation of symptoms were reviewed by the same radiologist, and tumor extent was determined.ResultsThe largest tumor diameter of the primary tumor was measured in 132 patients, 22 by an ultrasound and the other patients by a CT scan. In 53 patients, the tumor size could not be delimited and measured. Seventy-five patients (41%) had liver metastases at presentation of symptoms. Median survival for the entire patient group was only 119 days. The median diameter of the patient’s largest tumor was 4.35 cm, while the sample groups ranged from 1.2 to 14 cm. Patients were divided into two groups: those with a largest tumor diameter of ≤ 4.3 cm (66 patients) and those with a largest tumor diameter of > 4.3 cm (66 patients). Median survival for these groups was 149 and 94 days (p = 0.019), respectively. Cox regression showed a hazard ratio for tumor size of 1.48 (95% CI 1.02, 2.07) (p = 0.038), adjusted for the gemcitabine treatment which had been given to 49 patients and the presence of liver metastasis. In 88 patients, stricture length could be measured at ERCP. When comparing stricture lengths of ≤ 2 cm and > 2 cm, no difference in survival time was noted within a Kaplan-Meier analysis.ConclusionThe size of the maximum tumor diameter of the primary tumor during the initial X-ray examination of patients with pancreatic cancer may predict survival time for those patients who had no surgical resection. Stricture length at ERCP gave no information on survival.

A proposed model for prediction of survival based on a follow-up study in unresectable pancreatic cancer

“…Those patients with good performance status corresponding to a Karnofsky index above 50% received chemotherapy. We have previously found that survival analysis using the Kaplan-Meier method showed a better survival rate in unresectable pancreatic cancer if the tumour size was below 4.3 cm 2. By using Cox regression, adjusted for occurrence of liver metastases and performance status to decide if chemotherapy should start or not, the individual relative hazard was calculated.…”

“…Initial radiographs following admittance to the hospital were retrieved and re-examined, all by the same radiologist, and tumour size was measured again. For a more detailed description of this procedure of tumour evaluation see Forssell et al 2. In summary, most patients were examined with multislice CT with a slice thickness of 2 mm.…”

“…The disease is difficult to treat because clinical presentation is often late, and most of the patients have an advanced tumour burden with a high incidence of metastatic disease at diagnosis. In a recent Swedish study, tumour size—but not length of bile duct stricture—measured at the initial radiographic examination predicted the survival rate of patients with unresectable pancreatic cancer 2. Identifying factors that can accurately predict the duration of disease survival is potentially helpful in the treatment of patients with unresectable pancreatic cancer.…”

“…In a recent Swedish study, tumour size—but not length of bile duct stricture—measured at the initial radiographic examination predicted the survival rate of patients with unresectable pancreatic cancer. 2 Identifying factors that can accurately predict the duration of disease survival is potentially helpful in the treatment of patients with unresectable pancreatic cancer. It may be unsuitable for patients with a bulky tumour to be exposed to cytotoxic chemotherapy or other advanced palliative therapies, as it may not prolong their survival but instead impair the quality of their short remaining lives.…”

Thalidomide inhibits proliferation and epithelial‑mesenchymal transition by modulating CD133 expression in pancreatic cancer cells

“…Therefore, patients with pancreatic cancer have a poor prognosis, with an overall 5-year survival rate of <5% in the United States between 1975 and 2008 (2). No significant advances in the treatment of pancreatic cancer have been made in >10 years, largely due to of the resistance of the disease to conventional chemotherapy and radiation therapy (3)(4)(5)(6). The involvement of cancer stem cells (CSC; also termed tumor-initiating cells) in the development of chemotherapy resistance has been reported in a number of types of malignancy (7)(8)(9).…”