Margin negative resection and pathologic downstaging with multiagent chemotherapy with or without radiotherapy in patients with localized pancreas cancer: A national cancer database analysis

Innovative Imaging Techniques Used to Evaluate Borderline-Resectable Pancreatic Adenocarcinoma

A diagnosis of pancreatic cancer carries a 5-y survival rate of less than 10%. Furthermore, the detection of pancreatic cancer occurs most often in later stages of the disease due to its location in the retroperitoneum and lack of symptoms (in most cases) until tumors become more advanced. Once diagnosed, cross-sectional imaging techniques are heavily utilized to determine the tumor stage and the potential for surgical resection. However, a major determinant of resectability is the extent of local vascular involvement of the mesenteric vessels and critical tributaries; current imaging techniques have limited capacity to accurately determine vascular involvement. Surrounding inflammation and fibrosis can be difficult to discriminate from viable tumor, making determination of the degree of vascular involvement unreliable. New innovations in fluorescence and optoacoustic imaging techniques may overcome these limitations and make determination of resectability more accurate. These imaging modalities are able to more clearly discern between viable tumor tissue and non-neoplastic inflammation or desmoplasia, allowing clinicians to more reliably characterize vascular involvement and develop individualized treatment plans for patients. This review will discuss the current imaging techniques used to diagnose pancreatic cancer, the barriers that current techniques raise to accurate staging, and novel fluorescence and optoacoustic imaging techniques that may provide more accurate clinical staging of pancreatic cancer.

Preoperative downstaging of pancreatic cancer is associated with improved survival after multi-agent chemotherapy, but not after radiation

BACKGROUND

Downstaging has been associated with improved survival for many cancers. However, the implications of downstaging are unclear for pancreatic cancer in an era of effective neoadjuvant systemic chemotherapy.

METHODS

NCDB retrospective cohort study of resected pancreatic carcinoma treated with neoadjuvant therapy.

RESULTS

The study included 73,985 patients: 66,589 with no neoadjuvant therapy, 2,102 neoadjuvant radiation therapy (N-RT), 3,195 neoadjuvant multiagent chemotherapy (N-MAC) and 2.099 with both neoadjuvant radiation and multiagent chemotherapy. There was increased use of N-MAC over the period of this study. Patients selected for treatment with N-MAC had longer survival from surgery on univariate (23.1 vs. 18.7 months, p = < 0.01) and multivariate analyses HR 0.81 (0.76-0.87, p < 0.001) compared to those selected with N-RT. Downstaging was similar in N-RT and N-MAC groups (25.1 vs. 24.1%, p = 0.43). Downstaging following N-MAC was associated with a survival benefit, HR 0.85 (0.74-0.98). However, downstaging following N-RT was not associated with a survival advantage, HR 1.12 (0.99-0.99).

CONCLUSION

Clinicians have rapidly adopted N-MAC for treatment of pancreatic cancer. Although the rates of downstaging are similar between treatment groups, response translates into increased survival only with N-MAC and not with N-RT.

Patterns of Recurrence After Primary Local Therapy for Pancreatic Ductal Adenocarcinoma - A Critical Review of Rationale and Target Delineation for (Neo)Adjuvant Radiation Therapy

PURPOSE

The purpose of this work was to describe pancreatic ductal adenocarcinoma (PDAC) patterns of locoregional spread and recurrence to help guide clinicians on (neo)adjuvant radiation therapy (RT) planning strategies and target volume delineation.

METHODS AND MATERIALS

A comprehensive review of clinical data was performed to describe PDAC patterns of locoregional spread, including extrapancreatic tumor extension, perineural invasion, regional lymph node involvement, and patterns of disease recurrence as influenced by (neo)adjuvant treatment strategy.

RESULTS

This review describes PDAC patterns of spread, disease progression, and evolving treatment techniques. Based upon this data, we advocate for inclusion of elective at-risk regions of extrapancreatic extension, perineural invasion, and lymphatic spread for patients receiving neoadjuvant RT.

CONCLUSIONS

This review provides a nuanced description of PDAC patterns of spread and recurrence to guide clinicians on target volume delineation and planning strategies to maximize the effectiveness of neo(adjuvant) RT delivery for patients with PDAC. Further prospective studies are needed to better define the optimal RT dose, fractionation regimens, and target volumes to be used in the (neo)adjuvant setting.

Multiagent Chemotherapy Followed by Stereotactic Body Radiotherapy Versus Conventional Radiotherapy for Resected Pancreas Cancer

BACKGROUND AND PURPOSE

Chemotherapy followed by margin-negative resection (R0) is the treatment of choice for patients with localized pancreatic ductal adenocarcinoma (PDAC). Neoadjuvant multiagent chemotherapy (MAC) or MAC then radiotherapy (RT) may optimize surgical candidacy. The purpose of this study was to compare pathologic outcomes of MAC followed by conventionally fractionated radiotherapy (CRT) versus stereotactic body radiotherapy (SBRT) for patients with resected PDAC.

METHODS

Patients diagnosed with nonmetastatic PDAC between 2012 and 2017 and who received preoperative MAC or MAC+RT were identified in the National Cancer Database. Variables associated with R0 and overall survival were identified with logistic regression and Cox analysis (P<0.05).

RESULTS

A total of 5273 patients were identified (MAC: 3900, MAC+CRT: 955, MAC+SBRT: 418). The median RT dose/fraction (fx) in the MAC+CRT and MAC+SBRT cohorts was 50.4 Gy/28 fx and 33 Gy/5 fx. Patients receiving MAC+CRT versus MAC+SBRT had similar rates of ypT3-T4 disease (54% vs. 58%, P=0.187), R0 (87% vs. 84%, P=0.168), and pathologic complete response (pathologic complete response; 6% vs. 4%, P=0.052), however, MAC+CRT was associated with less regional lymphatic disease (ypN+: 28% vs. 41%, P<0.001). The median overall survival of patients receiving MAC+CRT versus MAC+SBRT was 24.6 versus 29.5 months (P=0.045).

CONCLUSIONS

For patients with resected PDAC, MAC+CRT, and MAC+SBRT had similar rates of R0 and pathologic complete response, although MAC+CRT was associated with lower ypN+. Prospective evaluation of neoadjuvant RT regimens with attention to radiation therapy design is warranted.

Incidence and Contemporary Management of Delayed Bleeding Following Pancreaticoduodenectomy

BACKGROUND

Delayed bleeding after pancreaticoduodenectomy (PD) is a life-threatening complication. However, the optimal management remains unclear. We summarize our experience of the management of delayed bleeding after PD and define the outcomes associated with different types of management.

METHODS

All patients who underwent a PD between January 1987 and June 2020 at Johns Hopkins University were retrospectively reviewed. Delayed bleeding was defined as bleeding on or after postoperative day 5 following PD. Incidence, outcomes, and trends were reported.

RESULTS

Among the 6201 patients that underwent PD, delayed bleeding occurred in 130 (2.1%) at a median of 12 days (IQR: 9, 24) postoperation. The pattern of bleeding was classified as intraluminal (51.5%), extraluminal (40.8%), and mixed (7.7%). A clinically relevant postoperative pancreatic fistula and an intraabdominal abscess preceded the delayed bleeding in 43.1% and 31.5% of cases, respectively. Arterial pseudoaneurysm or bleeding from peripancreatic vessels was the most common reason (54.6%) with the gastroduodenal artery being the most common source (18.5%). Endoscopy, angiography, and reoperation were performed as a first-line approach in 35.4%, 52.3%, and 6.2% of patients, respectively. The overall mortality was 16.2% and decreased over the study period (p < 0.01).

CONCLUSIONS

Delayed bleeding following PD remains a life-threatening complication. The most common location of delayed bleeding is from the gastroduodenal artery. Angiography with embolization should be the initial approach for urgent bleeding with surgical re-exploration reserved for unstable patients or failed control of bleeding after interventional angiography or endoscopy.