Factors influencing survival after resection for ductal adenocarcinoma of the head of the pancreas

Para-aortic lymph node involvement should not be a contraindication to resection of pancreatic ductal adenocarcinoma

BACKGROUND

Para-aortic lymph nodes (PALN) are found in the aortocaval groove and they are staged as metastatic disease if involved by pancreatic ductal adenocarcinoma (PDAC). The data in the literature is conflicting with some studies having associated PALN involvement with poor prognosis, while others not sharing the same results. PALN resection is not included in the standard lymphadenectomy during pancreatic resections as per the International Study Group for Pancreatic Surgery and there is no consensus on the management of these cases.

AIM

To investigate the prognostic significance of PALN metastases on the oncological outcomes after resection for PDAC.

METHODS

This is a retrospective cohort study of data retrieved from a prospectively maintained database on consecutive patients undergoing pancreatectomies for PDAC where PALN was sampled between 2011 and 2020. Statistical comparison of the data between PALN+ and PALN- subgroups, survival analysis with the Kaplan-Meier method and risk analysis with univariable and multivariable time to event Cox regression analysis were performed, specifically assessing oncological outcomes such as median overall survival (OS) and disease-free survival (DFS).

RESULTS

81 cases had PALN sampling and 17 (21%) were positive. Pathological N stage was significantly different between PALN+ and PALN- patients (P = 0.005), while no difference was observed in any of the other characteristics. Preoperative imaging diagnosed PALN positivity in one case. OS and DFS were comparable between PALN+ and PALN- patients with lymph node positive disease (OS: 13.2 mo vs 18.8 mo, P = 0.161; DFS: 13 mo vs 16.4 mo, P = 0.179). No difference in OS or DFS was identified between PALN positive and negative patients when they received chemotherapy either in the neoadjuvant or in the adjuvant setting (OS: 23.4 mo vs 20.6 mo, P = 0.192; DFS: 23.9 mo vs 20.5 mo, P = 0.718). On the contrary, when patients did not receive chemotherapy, PALN disease had substantially shorter OS (5.5 mo vs 14.2 mo; P = 0.015) and DFS (4.4 mo vs 9.8 mo; P < 0.001). PALN involvement was not identified as an independent predictor for OS after multivariable analysis, while it was for DFS doubling the risk of recurrence.

CONCLUSION

PALN involvement does not affect OS when patients complete the indicated treatment pathway for PDAC, surgery and chemotherapy, and should not be considered as a contraindication to resection.

Role of magnetic resonance imaging in the detection and characterization of solid pancreatic nodules: An update

Pancreatic ductal adenocarcinoma is the most common malignant tumor of the pancreas. The remaining pancreatic tumors are a diverse group of pancreatic neoplasms that comprises cystic pancreatic neoplasms, endocrine tumors and other uncommon pancreatic tumors. Due to the excellent soft tissue contrast resolution, magnetic resonance imaging (MRI) is frequently able to readily separate cystic from noncystic tumors. Cystic tumors are often easy to diagnose with MRI; however, noncystic non-adenocarcinoma tumors may show a wide spectrum of imaging features, which can potentially mimic ductal adenocarcinoma. MRI is a reliable technique for the characterization of pancreatic lesions. The implementation of novel motion-resistant pulse sequences and respiratory gating techniques, as well as the recognized benefits of MR cholangiopancreatography, make MRI a very accurate examination for the evaluation of pancreatic masses. MRI has the distinctive ability of non-invasive assessment of the pancreatic ducts, pancreatic parenchyma, neighbouring soft tissues, and vascular network in one examination. MRI can identify different characteristics of various solid pancreatic lesions, potentially allowing the differentiation of adenocarcinoma from other benign and malignant entities. In this review we describe the MRI protocols and MRI characteristics of various solid pancreatic lesions. Recognition of these characteristics may establish the right diagnosis or at least narrow the differential diagnosis, thus avoiding unnecessary tests or procedures and permitting better management.

Risk factors influencing recurrence following resection of pancreatic head cancer

AIM: Whether operative procedure is a risk factor influencing recurrence following resection of carcinoma in the head of pancreas or not remains controversies. In this text we compared the recurrence rate of two operative procedure: the Whipple procedure and extended radical operation, and inquired into the factors influencing recurrence after radical resection.

METHODS: From January 1995 to December 1998, 35 cases of carcinoma of pancreas underwent the Whipple operadure, 21 patients received the Extended radical operation. All patients were followed up for more than 3 years. Prognostic factors included operative procedure, size of tumor, lymph node, interstitial invasion.

RESULTS: Deaths duo to recurrence within 3 years after operation were studied. The death rate was 51.4% in the Whipple procedure and 42.9% in the Extended radical operative procedure. There was a significant difference between the two groups. Recurrence occurred in 75% patients with tumor large than 4 cm, in 87.5% patients with lymph node involvement, and in 50% patients with the presence of interstitial invasion.

CONCLUSION: Tumor exceeding 4 cm, lymph node involvement, and presence of interstitial invasion are high risk factors of recurrence after Whipple’s procedure and extended radical operation.

Significance of perigastric lymph node involvement in periampullary malignant tumor

AIM: To determine the perigastric lymph node involvement in periampullar tumors, in an attempt to optimize the surgical treatment of pylorus-preserving pancreatoduodenectomy.

METHODS: We retrospectively investigated the frequence of lymph nodes involvement in perigastric regions. Distribution and number of involved lymph nodes were exambined from 112 patients with carcinoma of pancreas, 59 patients with distal bile duct carcinoma, and 41 patients with carcinoma of the papilla of Vater.

RESULTS: The frequency of lymphatic spread of carcinoma in pancreas; distal bile duct and papilla of Vater was 18.7%, 1.9%, 2.5% respectively. With regard to the mode of lymphatic spread in perigastric region, Infrapyloric nodes of carcinoma of the head of pancreas predominated over others, in carcinomas of the distal bile duct and the papilla of Vater, the left gastric artery, and the greater curvature lymph nodes was the only sole sites, respectively.

CONCLUSION: Understanding perigastric lymphatic involvement in periampullary tumors may be helpful for choosing the appropriate surgical approaches to pancreatoduodenectomy with preservation of pylorus.