The standard chemotherapy agent for adjuvant treatment of pancreatic cancer (ductal adenocarcinoma of the pancreas) has typically been Fluorouracil (5-FU) based. But there have been other adjuvant agents and modalities for pancreatic cancer under study including gemcitabine, combined chemotherapy (multiple drug agents), and chemoradiation.
On behalf of the German Study Group for Pancreatic Cancer (a branch of the German Cancer Society), Riess and colleagues from a widely based consortium of community oncologists and oncology centers in Germany and Austria studied pancreatic cancer patients enrolled from 1998 until 2004 in 88 hospitals. The result of this work was published in the October 9, 2013 issue of the Journal of the American Medical Association.
The authors followed 368 patients who received substantive surgery for pancreatic cancer according to the extent of the disease and the dictates of the local hospitals’ protocols. These patients were randomized 1:1 to the no adjuvant therapy arm of the trial OR to the adjuvant therapy with gemcitabine arm of the trial (six months of chemotherapy with a weekly dosage at 700 mg/m2). There were 186 patients in the gemcitabine arm; 111 of the patients were able to receive all six cycles; 90% of patients in this arm received at least one single dose; 87% received at least one full gemcitabine cycle.
The pancreatic cancer patients in both arms of this Phase III trial were followed until September 2012. The data collection and coordination was undertaken by the Charité–Universitätsmedizin Berlin. The researchers found that the median overall survival of the patients in the gemcitabine arm was 22.8 months, compared with 20.2 months in the observation alone arm. This was found to be significant on a statistical basis.
Additionally, the five-year survival in the gemcitabine arm was 20.7%, compared with 10.4% in the observation alone arm. And the ten-year survival in the gemcitabine arm was 12.2%, compared with 7.7% in the observation alone arm.
The researchers suggest that gemcitabine has acceptable toxicity levels and confers survival advantage as adjuvant chemotherapy post-pancreatic cancer surgery.
Dale O’Brien, MD
The evaluation and diagnosis of pancreatic cancer (ductal adenocarcinoma of the pancreas) is now largely initially accomplished through radiographic means, including CT scanning. This has produced changes in related areas such as the staging of pancreatic cancer, and the evaluation for potential resection. Depending on tumor extension, as a part of the Whipple, the surgeon may need to surgically resect the superior mesenteric vein – portal vein complex (“SMV-PV”).
Researcher Katz and colleagues at the University of Texas / M.D. Anderson Cancer Center in Houston wondered if the necessity of the likelihood of this vascular aspect of the surgical procedure could be anticipated among resectable and borderline resectable cases using CT scan criteria. Their results were published in the February 2014 issue of the Journal of Gastrointestinal Surgery, the official publication of the Society for Surgery of the Alimentary Tract.
The researchers reviewed all patients who received the pancreaticoduodenectomy (Whipple procedure) at the M.D. Anderson Cancer Center for a seven year period (2004-2011). This process eventually yielded 254 pancreatic cancer patients who met inclusion standards (39.6% of these patients eventually required SMV-PV resection at surgery). The authors reexamined the CT images of these patients taken prior to surgery in regard to the extent of the tumor / SMV-PV interface in terms of four categories: no interface, less than or equal to 180° of interface, more than 180° of interface, or full occlusion.
The authors found that 89.5% of patients with either full occlusion of the vein complex or those with more than 180° of interface had received the SMV-PV resection. Also, they found that those with less than or equal to 180° of interface tended to have longer pancreatic cancer survival.
They conclude that this method of classification can be of help in pancreatic cancer surgical planning, and in prognosis. This is an interesting study suggesting fairly easy measurements that may that may prove to be very useful.
Dale O’Brien, MD
The possible cancer protective effects (including on pancreatic cancer) of aspirin and related drugs have been actively studied for the past twenty-five years or so. The initial work was noted and especially explored in colon cancer. There is conflicting research but the chemopreventive outcome of long-term aspirin use on cancer seems reasonably likely in colorectal cancer with probable but a lesser likelihood in other parts of the human GI tract. Research on long-term aspirin usage and pancreatic cancer (ductal adenocarcinoma of the pancreas) has yielded conflicting results.
The active ingredient in the bark of the willow tree (salicylic acid) was discovered in 1763 by Edward Stone of Oxford University UK. More than one hundred years later, this ingredient was first synthesized by the Bayer company in Germany, the “biotech” high flyer of its day. In modern times, aspirin is categorized in a class called nonsteroidal anti-inflammatory drugs (NSAIDs) that are each separated by slightly different mechanisms of action. The mechanisms of action of aspirin are myriad, but distinctively include being an irreversible cyclooxygenase (“COX”) enzyme inhibitor – both of the COX-1 and COX 2 pathways.
Qin and colleagues from Zhengzhou and Xinxiang, China conducted a meta-analysis of the chemopreventive possibility of aspirin intake in the medical literature and published the results in the January 2014 issue of the journal Pancreas. The authors identified ten studies that met their criteria for analysis which totaled 7,252 patients carrying a diagnosis of pancreatic cancer. They found that the odds ratio of taking a high dosage of aspirin was modestly protective against pancreatic cancer at 0.88. For Americans alone the odds ratio was 0.82. Low dosage intake of aspirin showed no apparent preventive advantage.
The distinction between high dose and low dose of aspirin intake may help explain the previous uneven research results in pancreatic cancer. An interesting result, we will have to watch for follow-up studies to better substantiate these findings.
Dale O’Brien, MD