Adjuvant therapy with chemotherapy and radiation therapy in the management of carcinoma of the pancreatic head

Role of chemoradiotherapy in the adjuvant and neoadjuvant settings for resectable pancreatic cancer

Pancreatic cancer is the 10th most commonly diagnosed malignancy in the USA and the fourth most common cause of cancer-related death. Worldwide, the mortality incidence ratio approaches 98%. Although only 15-20% of patients present with resectable disease, there is international consensus that complete surgical resection (R0, i.e. grossly and microscopically negative margins) is a vital part of any curative treatment paradigm. Despite advances in surgical technique, peri-operative care, chemotherapy and radiation delivery techniques over the past two decades, 5 year overall survival rates for resected pancreatic cancer with modern therapies remain around 20-25%. There is level I evidence for adjuvant chemotherapy in fully resected pancreatic cancer, but randomised trials examining the role of adjuvant chemoradiotherapy to date do not provide clear support for radiation therapy in this setting. In addition, efforts to increase the proportion of long-term survivors have recently centred on increasing the resectability of locoregional disease by incorporating neoadjuvant treatment before definitive surgery. Post-hoc analysis of randomised data as well as retrospective reviews have shown that there are several independent prognostic factors that may have considerable impact on survival outcomes, complicating interpretation and comparison of historical data. There is considerable interest in adjuvant and neoadjuvant therapy, but there is significant controversy as to whether radiation is of value, especially in the adjuvant context. Herein, we explore the sources of those controversies.

Radiotherapy in the adjuvant management of pancreatic adenocarcinoma: is it helpful?

Curative-intent management for pancreatic adenocarcinoma requires gross total resection. Only 15-20% of patients are eligible for resection and of these only approximately 20% are long-term survivors. Adjuvant and neoadjuvant approaches have been, and are being, sought to improve upon surgical results. Radiotherapy has a role in the adjuvant management of many gastrointestinal malignancies and historically has also had a role in the adjuvant management of pancreatic adenocarcinoma. However, the role of radiotherapy in the management of pancreatic adenocarcinoma has been called into question. This review examines this controversy and the underlying issues and considers current efforts towards resolving them, as well as some likely future developments.

Pancreatectomy for pancreatic cancer with reference to combined resection of the vessels, twenty nine year experience by a single surgeon

Between 1978 and 2007 one hundred and seven patients consecutively underwent resection for primary pancreatic adenocarcinoma. There were 28 pN0 patients, 41 pN1 and 37 pN2 or more (one unknown). Combined resection of the portal vein was performed in 62 out of 107 patients (58%). The hepatic artery in 10 patients, superior mesenteric artery in 8 patients and celiac trunk in 7 patients were also resected additionally to the portal vein. The 5-year survival rate and 10-year survival rate of all 107 cases were 12.1% and 2.8% respectively. The 5-year survival rate of the pN0 group was 37%, significantly better than the 14% 5-year survival rate in the pN1 group (p=0.043). Of 69 patients with pN0 or pN1, 38 patients underwent combined resection of the portal vein. There was not significant difference between the 24% 5-year survival rate in the group without the portal vein resection and the 19% 5-year survival rate in the group with portal vein resection. The 20% 5-year survival rate of the portal vein only group and the 5-year survival rate of both the portal vein and hepatic artery group were the same. The groups of the further resection of the superior mesenteric artery and of the celiac trunk showed no long-term survival. It is concluded that aggressive combined resection of the portal vein or additional resection of the hepatic artery be feasible for a survival benefit in pN0 and pN1 diseases.

3D radiotherapy can be safely combined with sandwich systemic gemcitabine chemotherapy in the management of pancreatic cancer: factors influencing outcome

PURPOSE

The aim of this Phase II study was to examine whether concurrent continuous infusion 5-fluorouracil (CI 5FU) plus three-dimensional conformal planning radiotherapy sandwiched between gemcitabine chemotherapy is effective, tolerable, and safe in the management of pancreatic cancer.

METHODS AND MATERIALS

Patients were enrolled in two strata: (1) resected pancreatic cancer at high risk of local relapse (postsurgery arm, n = 22) or (2) inoperable pancreatic cancer in head or body without metastases (locally advanced arm, n = 41). Gemcitabine was given at 1,000 mg/m(2) weekly for 3 weeks followed by 1 week rest then 5-6 weeks of radiotherapy and concurrent CI 5FU (200 mg/m(2)/day). After 4 weeks' rest, gemcitabine treatment was reinitiated for 12 weeks.

RESULTS

For the two arms combined, treatment-related Grade 3 and 4 toxicities were reported by 25 (39.7%) and 7 (11.1%) patients, respectively. No significant late renal or hepatic toxicity was observed. In the postsurgery arm (R1 54.5%), median time to progressive disease from surgery was 11.0 months, median time to failure of local control was 32.9 months, and median survival time was 15.6 months. The 1- and 2-year survival rates were 63.6% and 31.8%. No significant associations between outcome and mutations in K-ras or TP53 or microsatellite instability were identified. Post hoc investigation of cancer antigen 19-9 levels found baseline levels and increases postbaseline were associated with shorter survival (p = 0.0061 and p < 0.0001, respectively).

CONCLUSIONS

This three-dimensional chemoradiotherapy regimen is safe and promising, with encouraging local control for a substantial proportion of patients, and merits testing in a randomized trial.

Final results of a prospective trial of a PEFG (Cisplatin, Epirubicin, 5-Fluorouracil, Gemcitabine) regimen followed by radiotherapy after curative surgery for pancreatic adenocarcinoma

BACKGROUND

Postoperative management of patients with pancreatic adenocarcinoma (PA) is controversial.

METHODS

The aim of this pilot study was to assess the feasibility of postoperative combination chemotherapy followed by radiotherapy in patients aged 18-70 years with a histological diagnosis of PA, and Karnofsky performance status (KPS) > or =70. Cisplatin and epirubicin 40 mg/m2 on day 1, gemcitabine 600 mg/m2 on day 1 and 8, and 5-fluorouracil 200 mg/m2/day as protracted infusion (PEFG regimen) were delivered every 28 days for 4 cycles. Assuming a minimum one-year disease-free survival (DFS) of interest of 65% and a maximum of low interest of 45% (alpha 0.05; beta 0.10), the target enrollment was 51 patients, and the strategy would be considered to deserve further analysis if more than 29 patients were DF at one-year from surgery.

RESULTS

Fifty-one patients, KPS >80: 29, median tumor size 3.5 cm, stage II/III/IVA: 2/34/13, grade 3-4: 22, positive resection margins: 26, node positive: 46, received 179 cycles of chemotherapy. Main grade 3/4 toxicity consisted of neutropenia (51%), thrombocytopenia (18%), and anemia (4%). One-year DFS was 67 +/- 7%. Two-year overall survival was 53 +/- 7%.

CONCLUSION

Postoperative management of PA with this multimodality strategy was well tolerated and yielded a promising outcome.

Combined modality adjuvant therapy for resected periampullary pancreatic and nonpancreatic adenocarcinoma: a review of studies and experience at The Johns Hopkins Hospital, 1991-2003

In 1991 a multidisciplinary group consisting of surgeons, radiation oncologists, medical oncologists, pathologists, research nurses, and laboratory scientists was organized at the Johns Hopkins Hospital to accelerate progress in understanding the clinical and basic biology of pancreatic carcinoma and to develop research protocols aimed at improving clinical outcomes. This article discusses the studies, data, and conclusions generated to date, in some cases preliminarily, for the clinical trials and algorithms the Johns Hopkins team applied to the postoperative adjuvant management of periampullary pancreatic and nonpancreatic periampullary adenocarcinomas during the interval 1991 to 2003.

Adjuvant therapy for pancreatic adenocarcinoma: what have we learned since 1985?

To review developments relevant to pancreatic adjuvant therapy since the publication of the Gastrointestinal Tumor Study Group (GITSG) trial of adjuvant therapy for pancreatic cancer in 1985. Our understanding of the pathology, surgical management, clinical and pathologic prognostic factors, potential importance of adjuvant therapy, and optimal design of adjuvant therapies have all undergone major evolution. Available data suggest: (1) the morbidity of pancreaticoduodenectomy has been reduced substantially, especially in major referral centers; (2) physicians, patients, and families recognize the importance of clinical trials and substantial numbers of patients are available for such trials; (3) factors such as tumor size, margin status, nodal involvement, histologic differentiation, and blood loss at surgery have an impact on postoperative outcomes; (4) the use of gemcitabine and patient-specific, anatomic planning for conformal radiotherapy has the potential to radically alter the adjuvant paradigm; (5) vaccine therapies have completed Phase I testing and are being incorporated into Phase II trials; and (6) careful application of relevant statistical principles is necessary to avoid the execution of ambiguous or uninterpretable trials. The need for effective adjuvant therapy is undisputed, because surgery alone is inadequate. Increasing numbers of patients are undergoing and recovering from surgery who are willing to consider clinical trials. Major cooperative group and single-institution efforts recently completed, ongoing, or currently planned using improved stratification for prognostic subsets, translational approaches based on molecular biology and/or genetic engineering, and newer chemoradiotherapeutic regimens are rapidly changing the landscape of this clinical arena into one of promise and possibility.

Clinical research in pancreatic cancer: the Radiation Therapy Oncology Group trials

To summarize the clinical research activities of the Radiation Therapy Oncology Group program in the treatment of patients with locally advanced, as well as resected, pancreatic cancer. Phase II and III clinical trials are underway, examining novel cytotoxic and targeted agents with irradiation (RT) for patients with locally advanced and resected pancreatic cancer.A Phase II study incorporating concurrent paclitaxel with external beam radiotherapy in the locally advanced setting has been completed and recently analyzed. This experience has served as the foundation of a Phase II study using concurrent paclitaxel and gemcitabine with RT followed by R115777, a farnesyltransferase inhibitor, as maintenance therapy. In the adjuvant treatment of pancreatic cancer, an Intergroup Phase III trial has compared "conventional" postoperative chemoirradiation (5-fluorouracil before, after, and during RT) and gemcitabine before and after RT (with 5-fluorouracil during RT). This study has recently closed, meeting its accrual goal. The successor study will evaluate the use of gemcitabine given concurrently with RT, as well as in a maintenance schedule. This report summarizes current and future Radiation Therapy Oncology Group clinical trials in the treatment of patients with localized pancreatic cancer.

Novel allogeneic granulocyte-macrophage colony-stimulating factor-secreting tumor vaccine for pancreatic cancer: a phase I trial of safety and immune activation

PURPOSE

Allogeneic granulocyte-macrophage colony-stimulating factor (GM-CSF)-secreting tumor vaccines can cure established tumors in the mouse, but their efficacy against human tumors is uncertain. We have developed a novel GM-CSF-secreting pancreatic tumor vaccine. To determine its safety and ability to induce antitumor immune responses, we conducted a phase I trial in patients with surgically resected adenocarcinoma of the pancreas.

PATIENTS AND METHODS

Fourteen patients with stage 1, 2, or 3 pancreatic adenocarcinoma were enrolled. Eight weeks after pancreaticoduodenectomy, three patients received 1 x 10(7) vaccine cells, three patients received 5 x 10(7) vaccine cells, three patients received 10 x 10(7) vaccine cells, and five patients received 50 x 10(7) vaccine cells. Twelve of 14 patients then went on to receive a 6-month course of adjuvant radiation and chemotherapy. One month after completing adjuvant treatment, six patients still in remission received up to three additional monthly vaccinations with the same vaccine dose that they had received originally.

RESULTS

No dose-limiting toxicities were encountered. Vaccination induced increased delayed-type hypersensitivity (DTH) responses to autologous tumor cells in three patients who had received >or= 10 x 10(7) vaccine cells. These three patients also seemed to have had an increased disease-free survival time, remaining disease-free at least 25 months after diagnosis.

CONCLUSION

Allogeneic GM-CSF-secreting tumor vaccines are safe in patients with pancreatic adenocarcinoma. This vaccine approach seems to induce dose-dependent systemic antitumor immunity as measured by increased postvaccination DTH responses against autologous tumors. Further clinical evaluation of this approach in patients with pancreatic cancer is warranted.

Intensified adjuvant combined modality therapy for resected periampullary adenocarcinoma: acceptable toxicity and suggestion of improved 1-year disease-free survival

PURPOSE

(1) To determine the toxicity of an intensified postoperative adjuvant regimen for periampullary adenocarcinoma (pancreatic and nonpancreatic) utilizing concurrent 5-fluorouracil (5-FU), leucovorin (LV), dipyridamole (DPM), and mitomycin-C (MMC) combined with split-course locoregional external beam radiotherapy (EBRT) to 50 Gy. This was followed by 4 cycles of the same chemotherapy as adjuvant therapy. (2) To determine preliminary estimates of the overall and disease-free survival associated with the use of this regimen. (3) To compare the toxicities and early survival results of patients treated with the current regimen to those of patients who completed our prior trial of concurrent chemoradiation infusion with 5-FU/LV chemotherapy and regional nodal and prophylactic hepatic irradiation.

METHODS

Postpancreaticoduodenectomy, patients received every 4 weeks bolus administration of 5-FU, (400 mg/m(2)), and LV, (20 mg/m(2), Days l-3), DPM (75 mg p.o., 4 times per day, Days 0-3, and every 8 weeks), MMC, (10 mg/m(2); maximum of 20 mg, Day l during EBRT). This was followed by 4 months of the same chemotherapy, beginning 1 month following the completion of EBRT. EBRT consisted of split-course 5000 cGy/20 fractions with a 2-week planned rest after the first 10 fractions (2500 cGy).

RESULTS

From 4/96 to 6/99, 45 patients were enrolled and treated. Their experience constitutes the basis of this analysis. There were 29 patients with pancreatic cancer and 16 with nonpancreatic periampullary cancer. Seventeen patients had tumors of 3 cm or more, and 39 patients had at least 1 histologically involved lymph node. Thirteen patients had a histologically positive margin of resection. The mean time to start of treatment was 63 days following surgery. During chemoradiation therapy there were no Grade 3 or worse nonhematologic toxicities and 47% Grade 3 or Grade 4 hematologic toxicities of short duration. Following chemoradiation, during chemotherapy treatment only, there was one Grade 3 hepatic and one Grade 3 pulmonary toxicity which was nondebilitating (2% each case) and 42% Grade 3 or 4 hematologic toxicity. There were 2 episodes of neutropenic fever requiring admission and no treatment-related mortalities. One patient developed a mild case of HUS, which responded to standard management. One patient developed persistent shortness of breath (nondebilitating), and another patient had occasional dyspnea on exertion, both occurring after all therapy. The majority of patients complained of increased fatigue (Grade 1-2), greatest during the combined therapy and improving post all treatment. As of 6/23/99, 20 of 45 patients have relapsed, 13 in the liver. Twelve patients have died. Median follow-up for surviving patients is 14.3 months. Disease-free survival at 12 months following surgery is 66% (as compared to 25% in our prior study), and the median disease-free survival is 17 months (as compared to 8. 3 months in our prior study). Median survival has not yet been reached, but will be greater than 17 months.

CONCLUSION

With a 14.3-month median follow-up, acute toxicity has been acceptable and manageable. Observed relapses were seen 9-13 months following surgical resection. Early survival analysis suggests a trend toward increased median disease-free survival (8.3 vs. 17 months), especially for patients with nonpancreatic periampullary adenocarcinoma.

Chemoradiotherapy as preoperative treatment in locally advanced unresectable pancreatic cancer patients: results of a feasibility study

PURPOSE

The combination of radiotherapy and fluorouracil (5-FU) in patients with locally unresectable pancreatic carcinoma has led to a significant increase in survival in comparison with radiotherapy alone. Doxifluridine (5-DFUR) is an orally active fluoropyrimidine, and its cytotoxic metabolite (5-FU) may concentrate in areas of high tumor vascularization. This trial was carried out with the aims of improving locoregional control and making lesions resectable in patients with unresectable pancreatic cancer.

METHODS

5-DFUR was given at a dose of 500 mg/m2 b.i.d. by way of mouth for 4 days every other week for a total of four courses, with leucovorin 25 mg b.i.d. orally being given 2 hours before each 5-DFUR administration. External beam RT was administered at a dose of 1000 cGy per week for 3 weeks, followed by a 2-week break and then by 1000 cGy per week for a further 2 weeks (a total dose of 5000 cGy). The patients were restaged 4 weeks after the end of treatment and explored for resection in cases of partial response (PR).

RESULTS

A total of 32 patients were treated between 1992 and 1997. Ab initio unresectability was shown by laparotomy (16 cases) or computed tomography (16 cases), and was due to vascular invasion in 27 patients, massive regional nodal metastases in nine, and both in four. The median age was 63 years (range 36-71); performance status (PS) (ECOG): 0-1 = 28 and PS 2 = 4. All the patients had measurable disease and were evaluable for response. There were seven PR (22%), 10 SD (31%), and 15 PD (47%). All of the responders underwent surgical exploration, and radical resection was possible in 5. Three of these patients are still disease-free with a follow-up of 18, 27, and 65 months; the other two cases relapsed 11 and 14 months after surgery. The median survival time was 9 months for the entire group, and 1-year survival rate was 31%. The treatment was never stopped because of toxicity. There were no CTC-NCI grade 3 or 4 toxic events; grade 1-2 diarrhea was observed in 10 cases.

CONCLUSIONS

This preoperative regimen was feasible and led to a successful surgical resection in 16% of otherwise inoperable cases. The median survival was comparable with the results obtained after 5-FU infusion plus radiotherapy. The resectability rate, and the benefit in terms of survival in the resected patients, make these results worthy of confirmation by larger studies.

Intensified adjuvant therapy for pancreatic and periampullary adenocarcinoma: survival results and observations regarding patterns of failure, radiotherapy dose and CA19-9 levels

PURPOSE

Primary endpoints were 1. To determine if, in the context of postoperative adjuvant therapy of pancreatic and nonpancreatic periampullary adenocarcinoma, continuous infusion (C.I.) 5-fluorouracil (5-FU) and leucovorin (Lv), combined with continuous-course external-beam radiotherapy (EBRT) to liver (23.4-27.0 Gy), regional lymph nodes (50.4-54.0 Gy) and tumor bed (50.4-57.6 Gy), followed by 4 months of C.I. 5-FU/Lv without EBRT could be given with acceptable toxicity. 2. To determine an estimate of disease-free and overall survival (DFS, OS) with this treatment in this context. Secondary endpoints were 1. To observe the effects of therapy at two different dose levels of irradiation, and 2. To observe for correlations among DFS, OS and CA 19-9 levels during therapy.

METHODS

Patients received C.I. 5-FU 200 mg/m2 and Lv 5 mg/m2 Monday through Friday during EBRT, and 4 cycles of the same chemotherapy without EBRT were planned for each 2 weeks of 4, beginning 1 month following the completion of EBRT. Therapy was to begin within 10 weeks of surgery and patients were monitored for disease recurrence, toxicity, and CA 19-9 levels before the start of EBRT/5-FU/Lv, before each cycle of C.I. 5-FU/Lv, and periodically after the completion of therapy. There were two EBRT dosage groups: Low EBRT, 23.4 Gy to the whole liver, 50.4 Gy to regional nodes and 50.4 Gy to the tumor bed; High EBRT, 27.0 Gy to the whole liver, 54.0 Gy to regional nodes, and 57.6 Gy to the tumor bed.

RESULTS

29 patients were enrolled and treated (23 with pancreatic cancer, and 6 with nonpancreatic periampullary cancer). Of these, 18 had tumor sizes > or = 3 cm and 23 had at least one histologically involved lymph node; 6 had histologically positive resection margins. Mean time to start of EBRT/5-FU/Lv was 53 +/- 2 days following surgery. The first 18 patients were in the Low EBRT Group and the last 11 in the High EBRT Group. Toxicity was moderate and manageable, including a possible case of late radiation hepatitis. Median DFS was 8.3 months (pancreatic cancer patients 8.5 months) and OS was 14.1 months (pancreatic cancer patients 15.9 months). Among patients with pancreatic cancer, results were similar for the Low and High EBRT Groups (DFS: 8.3 vs. 8.6 months; OS: 14.4 vs. 16.9 months, respectively). With a mean follow up of 2.6 +/- 0.3 years for the surviving patients and a minimal follow-up of 2.5 years, 27 of 29 pts have relapsed and 25 pts have died. A rise in CA 19-9 levels preceded clinical relapse by 9.1 +/- 1.5 months. Time to first relapse by site showed inverse correlation with dose of radiotherapy to that site: peritoneal (5 +/- 1 month), hepatic (7 +/- 0.9 months), regional nodes/tumor bed (9.6 +/- 1.8 months). Mean postresection CA 19-9 level was 63.3 +/- 16.2 U/ml. Postresection CA 19-9 values did not correlate with survival, margin status, or with the identification of metastatic carcinoma in resected lymph nodes. However, among patients with histologically involved nodes in the resected specimen, postresection CA 19-9 values did correlate with the number of positive nodes identified (p = 0.05).

CONCLUSIONS

Although toxicity was acceptable, survival results were not improved over those seen with standard adjuvant treatment. Most patients relapsed before the planned chemotherapy cycles were completed, or within 100 days thereof, suggesting disease resistance to C.I. 5-FU/Lv as used in this study. Although this regimen is not recommended for further study, the doses of EBRT utilized may be suitable for evaluation with other chemotherapy combinations. Postoperative CA 19-9 levels did not correlate with survival, but did correlate with the number of histologically involved lymph nodes found in the resected specimen among node-positive patients. Moreover, rising CA 19-9 levels anticipated ultimate clinical failure by 9 months.

Adjuvant therapy for pancreatic cancer: back to the future

PURPOSE

The role of adjuvant therapy in the management of pancreatic cancer, resected with curative intent, remains controversial. This editorial review updates the status of adjuvant therapy in this context and introduces the first North American co-operative group study in this arena in roughly 20 years.

RESULTS

To the extent that there has been a "standard" of care in this context, it has been defined in large part by the early work of the Gastrointestinal Study Group (GITSG). Their trial was activated in the mid 1970's using split course radiation therapy and bolus 5-FU. In the intervening 20 + years the morbidity/mortality of pancreaticoduodenectomy (PDD) has been dramatically reduced; concurrently, understanding of prognostic factors impacting on outcomes for resected patients has been significantly enhanced. In major centers the mortality of PDD is roughly 1% and survival has been shown to correlate with a number of factors including tumor size, nodal involvement, and margin status. With currently available techniques doses of continuous course radiation therapy in the range of 50-55 Gy to sites of pancreatic tumor resection and adjacent lymph node regions have been given in a number of trials with acceptable morbidity. 5-FU sequencing and administration have been advanced and gemcitabine, an agent with clear radiosensitizing properties, has been approved for use against pancreatic cancer.

CONCLUSIONS

Following PDD increasing numbers of physiologically intact patients are confronting the survival statistics associated with resected pancreatic cancer. Their interest in improved therapeutic outcomes, combined with the noted improvements in radiation and chemotherapeutic management, has set the stage for renewed and intensified study. Accordingly, the intergroup mechanism of the Cancer Therapy and Evaluation Program (CTEP) of the NCI has designed, approved, and activated a modern Phase III, adjuvant protocol incorporating recently gained knowledge in this management context. Prospective randomization will be utilized to compare gemcitabine and 5-FU as single agents before and after chemoradiotherapy with 5-FU. Successful and timely completion of this newly activated intergroup study, RTOG 97-04, will establish a current, cooperative group experience, data base, and standard in the context of adjuvant therapy for pancreatic cancer and serve to provide momentum for further studies.

Cytokine-modified tumor vaccines: an antitumor strategy revisited in the age of molecular medicine

Technological advances and improved understanding of the biology of the immune response have resulted in a resurgence of interest in the use of tumor vaccination as a means to control cancer. Tumor vaccines genetically modified with cytokine genes comprise the greatest proportion of gene therapy approaches to cancer. Tumor cells obtained at resection of the primary tumor are grown in tissue culture and genetically modified with cytokine genes such that the vaccine cells, after injection, may stimulate immune recognition of tumor cells and generate immunologic memory to prevent future tumor recurrence. There are many unanswered questions regarding tumor vaccination including the optimal dose, optimal cytokine, injection technique including route and site of vaccine delivery, and methods of evaluating the immune response. Oncology nurses have an integral role in these areas as well as in evaluating patients for as yet undetermined side effects. As tumor vaccines receive increasing attention by the lay media, oncology nurses, especially those in the clinical research setting, must learn new terminology and concepts relevant to this new treatment approach in order to effectively translate the information to patients.

A novel strategy for inhibiting growth of human pancreatic cancer cells by blocking cyclin-dependent kinase activity

Pancreatic cancers frequently carry mutations in the K-ras, p53, and p16 genes, which regulate cell proliferation. Transition from G1 to S phase of the cell cycle requires activation of cyclin-dependent kinase 2 (Cdk2) which is inhibited by olomoucine and roscovitine. The purpose of this study was to determine whether olomoucine and roscovitine can block Cdk2 kinase activity and inhibit proliferation of four human pancreatic cancer cell lines with various genetic alterations. Human pancreatic carcinoma cell lines BxPC-3, PANC-1 Capan-2, and CAV were treated with olomoucine or roscovitine. Cdk2 kinase activity was determined using histone H1 as the substrate. Cell cycle distribution was analyzed by DNA flow cytometry. Cell numbers were quantitated by Coulter counter. Olomoucine and roscovitine blocked Cdk2 activity in all four pancreatic cancer cell lines. Both compounds also inhibited cell proliferation in a dose-dependent fashion. Roscovitine was at least threefold more potent than olomoucine for both Cdk2 activity and cell proliferation. We have shown that Cdk inhibitors, olomoucine and roscovitine, block proliferation of human pancreatic cancer cells regardless of their mutations in K-ras p53, or p16 genes. These compounds represent a novel therapeutic strategy with potential therapeutic benefits for pancreatic cancers.

Adjuvant radiation therapy for pancreatic cancer: a 15-year experience

PURPOSE

A retrospective analysis to determine differences in survival of patients with pancreatic adenocarcinoma treated by radical surgery with and without adjuvant radiation therapy.

METHODS AND MATERIALS

Between 1980 and 1995, 249 patients with pancreatic tumors were identified at the Medical College of Ohio. Forty-four of these patients underwent radical surgical procedures with curative intent. These patients were divided into four groups according to treatment: surgery alone (n = 14), surgery plus intraoperative radiation therapy (IORT) (n = 6), surgery plus external beam radiation therapy (EBRT) (n = 14), or surgery plus both IORT and EBRT (n = 10). Outcome and survival were analyzed among the four groups.

RESULTS

The median survival time of patients treated with radical surgery alone was 6.5 months. The median survival time for the surgery plus IORT group was 9 months; however, 33.3% (two of six) of these patients survived longer than 5 years. This survival pattern was borderline significantly better than that for the surgery alone group (p = 0.0765). The surgery plus EBRT and the surgery plus IORT and EBRT groups had median survival times of 14.5 and 17.5 months, respectively. These were significantly better than that of the surgery alone group (p = 0.0004 and p = 0.0002, respectively). The addition of radiation therapy did not affect the treatment complication rate.

CONCLUSION

The survival of patients who were treated with radical surgery alone was significantly poorer than that of patients who received adjuvant radiation therapy. These results are consistent with other studies in the literature. Patients treated with all three modalities (surgery, IORT, and EBRT) displayed the best median survival time.

Results of adjuvant therapy in resected pancreatic cancer

After an apparently curative resection, most patients develop local recurrence within the resection bed. In addition, almost all develop liver metastases. This implies that the surgical resection, even if extended, seldom is enough, and that an adjuvant treatment must be effective not only against systemic spread, but also against local recurrence. However, the time schedule may be different for different types of recurrence, resulting in different time frames for the adjuvant treatment. Although extended radical operations may increase the proportion of patients who can undergo resections, the incidence of local recurrences seems unchanged. There are, however, no randomized studies yet comparing the "Standard Whipple" with more extended resection. Intraoperative radiation (IORT) has failed to demonstrate a difference in long-term survival, but there have been reports of a decreased frequency of local progression at the site of the primary tumor. Therefore, it is encouraging that IORT seems to diminish the local recurrences after radical resections. However, randomized studies are also missing for this procedure. These are today only three published studies of adjuvant chemotherapy after radical pancreaticoduodenectomy, but a few more will be finished shortly. Still, the results have not convincingly shown that modern chemotherapy with or without radiotherapy prolongs the life of the patients, and there is little evidence for improving the quality of life. However, since the results are far from satisfactory after resection, more efforts should be made to find better treatment modalities, including adjuvant protocols.