Role of adjuvant therapy in the management of pancreatic cancer

Survival impact based on hepatic artery lymph node status in pancreatic adenocarcinoma: A study of patients receiving modern chemotherapy

BACKGROUND

Chemotherapy for pancreatic adenocarcinoma (PDAC) has significantly improved in recent years. While the involvement of the hepatic artery lymph node (HALN; station 8a lymph node) likely represents advanced disease, a comparison to patients with metastases on modern chemotherapy is lacking.

METHODS

Patients who underwent pancreatoduodenectomy with HALN sent for pathologic review at a single institution from 2003 to 2018 were reviewed. Patients who presented with liver-only metastases at the time of PDAC diagnosis (Stage IV) and received chemotherapy were identified. Multivariate Cox proportional hazards regression modeling was utilized and overall survival (OS) was estimated using Kaplan-Meier analysis.

RESULTS

Of the 112 patients with a HALN sent for analysis, 17 (15%) were positive and 13 (76%) received chemotherapy. Ninety-four stage IV patients were identified and were significantly more likely to have received a multiagent rather than single-agent chemotherapy regimen compared to HALN positive patients (79.8% vs. 38.5%, p < .001). Median OS was significantly longer in all patients who underwent surgical resection, regardless of HALN status, compared to stage IV patients.

CONCLUSIONS

Patients undergoing pancreatoduodenectomy with HALN positivity have significantly improved OS compared to patients with stage IV disease. HALN involvement does not significantly alter survival among resected patients and does not warrant preoperative endoscopic ultrasound-guided biopsy.

Adjuvant and neoadjuvant treatment in pancreatic cancer

Pancreatic adenocarcinoma is one of the most aggressive human malignancies, ranking 4th among causes for cancer-related death in the Western world including the United States. Surgical resection offers the only chance of cure, but only 15 to 20 percent of cases are potentially resectable at presentation. Different studies demonstrate and confirm that advanced pancreatic cancer is among the most complex cancers to treat and that these tumors are relatively resistant to chemotherapy and radiotherapy. Currently there is no consensus around the world on what constitutes “standard” adjuvant therapy for pancreatic cancer. This controversy derives from several studies, each fraught with its own limitations. Standards of care also vary somewhat with regard to geography and economy, for instance chemo-radiotherapy followed by chemotherapy or vice versa is considered the optimal therapy in North America while chemotherapy alone is the current standard in Europe. Regardless of the efforts in adjuvant and neoadjuvant improved therapy, the major goal to combat pancreatic cancer is to find diagnostic markers, identifying the disease in a pre-metastatic stage and making a curative treatment accessible to more patients. In this review, authors examined the different therapy options for advanced pancreatic patients in recent years and the future directions in adjuvant and neoadjuvant treatments for these patients.

Advances in early diagnosis and therapy of pancreatic cancer

BACKGROUND

Pancreatic cancer remains a devastating disease with a 5-year survival rate of less than 5%. Recent advances in diagnostic methods and therapeutic approaches have increased the possibility of improving the existing poor prognosis.

DATA SOURCES

English-language articles reporting early diagnosis and therapy of pancreatic cancer were searched from the MEDLINE and PubMed databases, Chinese-language articles were from CHKD (China Hospital Knowledge Database).

RESULT

The current literature about pancreatic cancer was reviewed from three aspects: statistics, screening and early detection, and therapy.

CONCLUSIONS

Early detection and screening of pancreatic cancer currently should be limited to high risk patients. Surgical resection is the only curative approach available, with some recent improvement in outcomes. Gemcitabine has been a standard treatment during the last decade. Gemcitabine-based combination treatment, especially combined with newer molecular targeted agents, is promising. The rationale for radiotherapy is controversial, but with the recent development of modern radiation delivery techniques, radiotherapy should be intensified. Patients with borderline pancreatic cancer could benefit from neoadjuvant therapy but more evidence is needed and the best neoadjuvant regimen is still to be determined.

Patterns of EphA2 protein expression in primary and metastatic pancreatic carcinoma and correlation with genetic status

EphA2 is a transmembrane receptor tyrosine kinase that functions in the regulation of cell growth, survival, angiogenesis, and migration and EphA2 targeting has been proposed as a novel therapeutic strategy for neoplasms that overexpress this protein. EphA2 overexpression has been correlated with increased invasive and metastatic ability in pancreatic cancer cell lines. However, the patterns of EphA2 expression in human pancreatic cancers and associated metastases is unknown, as are the genetics of EphA2 in this tumor type. We collected clinicopathologic data and paraffin-embedded materials from 98 patients with primary and/or metastatic pancreatic cancer and performed immunohistochemical labeling for EphA2 protein. EphA2 protein immunolabeling was found in 207 of 219 samples (95%). The expression was predominantly cytoplasmic, although predominant membranous staining was observed in a minority of cases. When evaluated specifically for labeling intensity, primary and metastatic carcinomas were more strongly positive compared to benign ducts and PanIN lesions (P < 0.00001 and P < 0.01, respectively) and poorly differentiated carcinomas were more strongly positive for EphA2 than well and moderately differentiated tumors (P < 0.005). When primary carcinomas without metastatic disease were specifically compared to carcinomas with associated metastatic disease, the advanced carcinomas showed relatively less strong positive labeling for EphA2 (P < 0.008). Moreover, decreased EphA2 labeling was more commonly found in liver (P < 0.002), lung (P < 0.004) or peritoneal metastases (P < 0.01) as compared to distant lymph node metastases (P < 0.01). Genetic sequencing of the tyrosine kinase domain of EPHA2 in 22 samples of xenograft enriched pancreatic cancer did not reveal any inactivating mutations. However, EPHA2 amplification was found in 1 of 33 pancreatic cancers corresponding to a lymph node metastasis, indicating EPHA2 genomic amplification may underlie EphA2 overexpression in a minority of patients. Our data confirms that EphA2 is overexpressed in pancreatic cancer, but suggests a relative loss of EphA2 in co-existent pancreatic cancer metastases as well as a role for EPHA2 in organ specific metastasis.