Long-term survivors after operation on carcinoma of the pancreas

Pancreatic Cancer: 80 Years of Surgery-Percentage and Repetitions

Objective. The incidence of pancreatic cancer is estimated to be 48,960 in 2015 in the US and projected to become the second and third leading causes of cancer-related deaths by 2030. The mean costs in 2015 may be assumed to be $79,800 per patient and for each resection $164,100. Attempt is made to evaluate the results over the last 80 years, the number of survivors, and the overall survival percentage. Methods. Altogether 1230 papers have been found which deal with resections and reveal survival information. Only 621 of these report 5-year survivors. Reservation about surgery was first expressed in 1964 and five-year survival of nonresected survivors is well documented. Results. The survival percentage depends not only on the number of survivors but also on the subset from which it is calculated. Since the 1980s the papers have mainly reported the number of resections and survival as actuarial percentages, with or without the actual number of survivors being reported. The actuarial percentage is on average 2.75 higher. Detailed information on the original group (TN), number of resections, and actual number of survivors is reported in only 10.6% of the papers. Repetition occurs when the patients from a certain year are reported several times from the same institution or include survivors from many institutions or countries. Each 5-year survivor may be reported several times. Conclusion. Assuming a 10% resection rate and correcting for repetitions and the life table percentage the overall actual survival rate is hardly more than 0.3%.

Treatment of pancreatic cancer: challenge of the facts

Adenocarcinoma of the pancreas is associated with the worst survival of any form of gastrointestinal malignancy. In spite of the progress in surgical treatment, resulting in increasing resection rates and a decrease in treatment-related morbidity and mortality, the true figures of cure are even today below 3%. The dissemination of pancreatic cancer behind the local tissue compartments restricts the short-term (< 3 years) and long-term outcome for patients who have undergone resection. By histological evaluation, less than 15% of the patients undergoing R(0) resection have a pN(0) status, more than 60% suffer from lymph angiosis carcinomatosa, and more than 50% suffer extrapancreatic nerve plexus infiltration. Hematoxylin and eosin-negative lymph nodes were found to be cancer positive when reverse transcriptase polymerase chain reaction (RT- PCR) or immunostaining was applied to the HE-negative lymph nodes. Cancer of the uncinate process has a very poor prognosis because there are no early symptoms; vessel wall involvement occurs early and frequently; a high association of liver metastasis exists as well. Surgery offers a low success rate, but it provides the only chance of cure. Ductal pancreatic cancer is diagnosed in more than 95% of the cases in an advanced stage; potentially curative resection can be performed only in about 10%-15% of these patients. Major contributions of surgery to improved treatment results are the reduction of surgical morbidity--e.g., early postoperative local and systemic complications--and a decrease of hospital mortality below 3%-5%. In most recently published prospective trials, R(0) resection has been reported to result in an increase in short-term survival beyond that recorded for patients with residual tumor. However, R(0) resection fails to improve long-term survival. In many published R(0) series, standard tissue resection of pancreatic head cancer with the Kausch-Whipple procedure failed to include remote cancer cell-positive tissues in the operative specimen; e.g., N(2)-lymph nodes, nerve plexus, and perivascular extrapancreatic and retropancreatic tissues were not excised. Cancer recurrence after so-called R(0) resection with curative intent is frequently the consequence of cancer left behind. Thus, long-term survival (> 5 years) is observed in a very small group of patients, contradicting the published 5-year actuarial survival rates of 20%-45% for resected patients. The assessment of clinical benefit from surgical or medical cancer treatment should therefore be based on several end points, not only on actuarial survival. Publication of actuarial survival figures must include the number of observed (actual) survivals, the definition of the subset of patients followed after resection, and the total number of patients in the study group; anything less is misleading. In reporting pancreatic cancer treatment trial results after oncological resections, more convincing primary end points to evaluate treatment efficacy are median survival (in months), actual survival at 1-5 years, and progression-free survival (in months). In series with multimodality treatment, clinical benefit response as well as quality of life measurements using the EORTC Quality of Life index C30 (QLQ-C30) are of importance in evaluating survival data. Adjuvant treatment improves survival after oncological resection; however, the short-term and long-term benefit after adjuvant chemotherapy in R(0) as well as in R(1)-(2) resected patients has not yet been underscored by data from controlled clinical trials. The survival benefit (median survival time) of adjuvant chemotherapy or radiochemotherapy has been demonstrated to be 6-10 months. Therefore, after oncological resection of pancreatic cancer each patient should be offered adjuvant treatment. A neoadjuvant treatment protocol for pancreatic cancer, however, has not been established.

Long-term survival after resection for ductal adenocarcinoma of the pancreas. Is it really improving?

OBJECTIVE

The authors review their recent experience with resected pancreatic ductal adenocarcinoma.

SUMMARY BACKGROUND DATA

Ductal adenocarcinoma of the pancreas has traditionally had a 5-year survival rate less than 10% after curative resection. Recently, several groups have reported markedly improved 5-year survival rates (approaching 25%) for patients undergoing curative resection.

METHODS

Institutional experience with 186 consecutive patients (1981-1991) with pathologic diagnoses of ductal adenocarcinoma undergoing pancreatic resection was reviewed. Histologic specimens of all 3-year survivors (n = 31) were re-reviewed by two pathologists, one internal and one external; nonductal pancreatic cancers then were excluded.

RESULTS

After histologic re-review, 12 patients did not have ductal adenocarcinoma, leaving a total of 174 patients for analysis (102 men, 72 women; mean age 63 years, range 34-82 years). Mean follow-up was 22 months (range 4-109). Classical pancreaticoduodenectomy was performed in 71%, pylorus-preserving resection in 9%, and total pancreatectomy in 20%. Hospital mortality was 3%. Twenty-eight patients (16%) had macroscopically incomplete resections; 98 (56%) had lymph node metastases within the resected specimens, and 21 patients (12%) had extensive perineural invasion. Overall actuarial 5-year survival was 6.8%. Five-year survival was greater for node-negative versus node-positive patients (14% vs. 1%, p < 0.001), and for smaller (< 2 cm) versus larger tumors (20% vs. 1%, p < 0.001). The 5-year survival for the subset of patients with negative nodes and no perineural or duodenal invasion (69 patients) was 23% (p < 0.001). Mean survival of the 12 excluded patients was 53 +/- 7 months compared with 17.5 +/- 1 months in the 174 patients with ductal pancreatic cancer.

CONCLUSIONS

Five-year survival for patients undergoing pancreatic resection for lesions deemed to be clinically "curable" intraoperatively and histologically reviewed/confirmed to be ductal adenocarcinoma of the pancreas is approximately 7%. Survival is greater (23%) in the subset of patients with negative nodes and no duodenal or perineural invasions. Pathologic review of all patients with pancreatic ductal cancer adenocarcinoma is mandatory if survival data are to be meaningful.

Ductal adenocarcinoma of the pancreas. Histopathological features and prognosis

Between 1972 and 1987, curative surgical resection (RO) was performed in 81 patients with ductal adenocarcinoma of the pancreas. In this study, slides from surgical specimens were reviewed, and histopathological features of the carcinomas were retrospectively reevaluated. Tumor stage was the most important prognostic factor: In UICC stages I, II, and III, the median survival times were 13, 16, and 8 mo, respectively. Lymph node involvement and direct extension of the tumor into adjacent peripancreatic tissue, as well as invasion into peripancreatic organs were found to significantly influence survival. Tumor infiltration of the lymphatic vessels was present in 74% of the resected carcinomas and significantly correlated with survival time. There was no relationship between survival and tumor size; furthermore, histological grade of differentiation, age, and sex had no influence on prognosis.

UICC and Japanese stage classifications for carcinoma of the pancreas

The stage classification (SC) for carcinoma of the pancreas recommended by UICC (UICC-SC) was compared with that of Japan Pancreas Society (JPN-SC) using 229 patients encountered consecutively at the Second Department of Surgery, Nagasaki University School of Medicine over the past 20 yr. By UICC-SC, 51% of the patients belonged to stage IV and 38% to Stage III. By JPN-SC, 82% of the patients belonged to stage IV. Curative resection rates in JPN stage II and III were significantly higher than those in UICC-SC by the chi-squared test. In 60 patients undergoing resectional surgery, postoperative cumulative survival (PCS) curves and rates by each staging criterion (tumor size [T], lymph node metastasis [N], distant metastasis [M], serosal invasion [S], retroperitoneal invasion [Rp], and invasion to the portal venous systems [V]) were calculated by the Kaplan-Meier method. Among these prognostic factors, significant differences in the PCS curves were demonstrated only between Rp(-) and Rp(+), and between V(-) and V(+) according to the generalized Wilcoxon's text. In UICC-SC, the underestimation of these factors leads to a tendency to classify the patients in a less advanced stage than in JPN-SC. JPN-SC is more complex than UICC-SC. Continuing efforts are necessary to establish a more practical, simple, and universal staging system for the disease.

Tumor size as a predictive factor

Is tumor size a predictive factor in carcinoma of the pancreas? In order to answer this question, the data of the Japan Pancreatic Cancer Registry from 1981 to 1987 were retrospectively analyzed. Of the 7687 cases that were registered, 5826 cases (75.7%) were laparotomized. Out of the 5826, 2311 (39.7%) underwent resection. Postoperative deaths within 1 mo among resected cases numbered 104, and the operative mortality rate was 4.5%. The postoperative survival rates were calculated by Kaplan-Meier's method. They clearly showed that the rates for small carcinomas (greater than 2 cm [T1]) were significantly higher than those for the tumors larger than 2 cm (T2, T3, T4) according to the Greenwood formula. Although the survival-rate calculation excluded operative deaths and deaths of causes other than pancreatic cancer, and included islet cell carcinoma, cystadenocarcinoma, and acinar cell carcinoma, it seems that tumor size may be a predictive factor for postoperative prognosis. However, our previous study on long-term survivors (more than 5 yr) after resection on the exocrine pancreatic cancer) revealed that there was no relation between the size of tumor and the postoperative prognosis. In those long-term survivors, there was no definite or severe cancerous invasion of either the retroperitoneal tissue or the portal venous system. It is concluded that a tumor 2 cm or smaller has a significantly better prognosis after resection than does a tumor larger than 2 cm, and it seems, in general, that tumor size may be a predictive factor. However, if the tumor does not invade the retroperitoneal tissue or the portal venous system, tumor size per se is not always a predictive factor.