A review of splenic pathology in distal pancreatectomies

Distal pancreatectomy for pancreatic neoplasia: is splenectomy really necessary? A bicentric retrospective analysis of surgical specimens

BACKGROUND

While distal pancreatectomy with splenectomy (DPS) is the reference treatment for pancreatic body and tail neoplasia, oncological benefits of splenectomy have never been demonstrated. Involvement of spleen, splenic hilum and lymph nodes (LN) was therefore assessed on DPS specimens.

METHODS

All DPS pancreatic neoplasia specimens obtained in 2 Brussels University Hospitals over 15 years (2004-2018) were reviewed retrospectively, using both preoperative radiological imaging and postoperative pathological analyses of splenic parenchyma, hilar tissue and LN.

RESULTS

The total of 130 DPS specimens included 85 adenocarcinomas, 37 neuroendocrine neoplasms and 8 other carcinomas. Tumours involved the pancreatic body without tail invasion for 59 specimens (B, Body group), and the pancreatic tail with/without body for 71 (T, Tail group). At pathology, direct splenic and/or hilar involvement was observed in 13 T specimens (13/71, 18.3%), but in none belonging to the Body group. The observed numbers of splenic hilar LN (only reported in 49/130 patients) were low, only one T adenocarcinoma had positive splenic LN in addition to direct splenic involvement.

CONCLUSION

Splenectomy remains justified during pancreatectomy for neoplasia involving the pancreatic tail, but in case of pancreatic body tumours, its benefits should be questioned in the light of absent splenic LN/parenchymal involvement.

Role of lymphadenectomy in resectable pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) remains one of the most devastating malignant diseases, predicted to become the second leading cause of cancer-related death by 2030. Despite advances in surgical techniques and in systemic therapy, the 5-year relative survival remains a grim 9% for all stages combined. The extent of lymphadenectomy has been discussed intensively for decades, given that even in early stages of PC, lymph node (LN) metastasis can be detected in approximately 80%.

PURPOSE

The primary objective of this review was to provide an overview of the current literature evaluating the role of lymphadenectomy in resected PC. For this, we evaluated randomized controlled studies (RCTs) assessing the impact of extent of lymphadenectomy on OS and studies evaluating the prognostic impact of anatomical site of LN metastasis and the impact of the number of resected LNs on OS.

CONCLUSIONS

Lymphadenectomy plays an essential part in the multimodal treatment algorithm of PC and is an additional therapeutic tool to increase the chance for surgical radicality and to ensure correct staging for optimal oncological therapy. Based on the literature from the last decades, standard lymphadenectomy with resection of at least ≥ 15 LNs is associated with an acceptable postoperative complication risk and should be recommended to obtain local radicality and accurate staging of the disease. Although radical surgery including appropriate lymphadenectomy of regional LNs remains the only chance for long-term tumor control, future studies specifically assessing the impact of neoadjuvant therapy on extraregional LNs are warranted.

Is Routine Splenectomy Justified for All Left-Sided Pancreatic Cancers? Histological Reappraisal of Splenic Hilar Lymphadenectomy

BACKGROUND

Although splenectomy is recommended during resection for left-sided resectable pancreatic ductal adenocarcinoma (PDAC) to perform lymphadenectomy of station 10 (splenic hilum), no level I evidence justifies this procedure. This study aims to evaluate the rate of lymph node (LN) and contiguous involvement of the splenic hilum in resectable distal PDAC.

METHODS

We retrospectively reviewed all patients who underwent splenopancreatectomy for PDAC in the past 10 years. Station 10 LN were routinely isolated, and all corresponding microscopic slides were reinterpreted by a pathologist. The computed tomography (CT) results of patients with tumoral involvement of the spleen or splenic hilum by contiguity (TISOSH) and ≤ 10 mm between the tumor and spleen on pathology were blindly reviewed by two radiologists to evaluate CT for diagnosis of TISOSH.

RESULTS

We included 110 consecutive patients, including 104 with analyzable station 10 LN. The tumor was N+ in 58 (53%) patients. The median number of LN identified at station 10 was 2.0 ± 3.0. No station 10 LNs were detected in 42 (40%) patients. No patients had tumor-positive LN at station 10. TISOSH was found in nine (8%) patients, and was significantly associated with tail location (p = 0.001), tumor size (p = 0.005), and multivisceral involvement (p = 0.015). For diagnosis of TISOSH, the sensitivity and specificity of CT were respectively 89% and 95% for radiologist 1 and 89% and 100% for radiologist 2.

CONCLUSIONS

Splenic preservation during resection of distal PDAC may be an option in selected patients with body tumors and no suspected splenic or splenic hilum involvement on preoperative CT.

Visceral Thromboses in Pancreas Adenocarcinoma: Systematic Review

Within gastrointestinal malignancies, primary hepatocellular carcinoma and pancreatic ductal adenocarcinoma (PDAC) are frequently associated with visceral thromboses (VT). Thrombus formation in the portal (PVT), mesenteric (MVT), or splenic vein (SVT) system leads to portal hypertension and intestinal ischemia. VT in PDAC may convey a risk of increased distal thrombosis and poses therapeutic uncertainty regarding the role of anticoagulation. An increasing number of reports describe VT associated with PDAC. It is possible that early diagnosis of these events may help reduce morbidity and speculatively improve oncologic outcomes. To perform a systematic review to study PVT, MVT, and SVT associated with PDAC, and to provide a comprehensive review. Medline/PubMed, Embase, Web of Science, Scopus, and the Cochrane Library. Data Extraction and Assessment: Two blinded independent observers extracted and assessed the studies for diagnosis of PVT, MVT, and SVT in PDAC. Studies were restricted to English-language literature published between 2007 and 2016. Eleven articles were identified. Five case reports and 7 retrospective studies were found, with a total of 127 patients meeting the inclusion criteria. The mean age at diagnosis was 64 years. PVT was found in 35% (n = 46), SVT in 52% (n = 65), and MVT in 13% (n = 15). Mean follow-up time was 26 months. Only 3 of the selected articles studied the impact of anticoagulation in VT. All patients with nonvisceral thrombosis (eg, deep-vein thrombosis, pulmonary emboli) were therapeutically treated; in contrast, patients with VT only rarely received treatment. VT in PDAC is a frequent finding at diagnosis or during disease progression. Evidence to guide treatment choices is limited, and current management is based on inferred experience from nononcologic settings. Anticoagulation appears to be safe in VT, with most of the large studies recommending a careful assessment for patients at a high risk of bleeding.