Systemic Therapy for Patients With Pancreatic Cancer: Current Approaches and Opportunities for Novel Avenues Toward Precision Medicine

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis with a 5-year overall survival of 11%. The disease is usually diagnosed at advanced stages, and systemic chemotherapy is the standard-of-care treatment for the majority of patients with PDAC. Although novel treatment options, such as targeted therapy and immunotherapy, have achieved substantial progress leading to practice-changing results, with FDA approvals for several solid tumors so far, the progress achieved for PDAC is relatively limited. Recent studies uncovered potential therapeutic targets for patients with PDAC, and potential therapeutic opportunities are currently being further examined. Herein, we review recent advances in systemic therapy regimens, including cytotoxic agents, targeted therapies, immunotherapy, and novel therapeutic options for managing patients with PDAC. We also elaborate on molecular profiling to guide treatment and existing therapeutic opportunities that may further advance the clinical care of patients with this devastating disease.

Investigating the Association Between rs2439302 Polymorphism and Thyroid Cancer: A Systematic Review and Meta-Analysis

Background and Aims

The extent of surgical treatment for most patients with thyroid cancer (TC) remains controversial and varies widely. As an emerging technology, genetic testing facilitates tumor typing and disease progression monitoring and is expected to influence the choice of surgical approach for patients with TC. Recent genome-wide association studies (GWASs) have identified that rs2439302 (8p12) variants near NRG1 are associated with TC risk; however, the results remain inconclusive. Therefore, we aimed to perform a meta-analysis to clarify the association between rs2439302 variants and the risk of TC.

Methods

We search eligible studies using Pubmed, Scopus, Embase, Web of Science, and Cochrane library by July 2021. We analyzed the pooled OR and the corresponding 95% confidence interval (95% CI) of the included studies and then conducted subgroup analysis according to the ethnicity. We also performed a sensitivity analysis to validate the findings.

Results

This meta-analysis finally included 7 studies involving 6,090 cases and 14,461 controls. Results showed that the G allele of the rs2439302 polymorphism was a significant risk factor of TC in Allele (G/C), Dominant (GG+GC/CC), Recessive (GG/GC+CC), Homozygote (GG/CC), Heterozygote (GC/CC) models, with pooled ORs of 1.38 (95%CI, 1.31–1.45), 1.51 (95%CI, 1.41–1.62), 1.52 (95%CI, 1.40–1.66), 1.90 (95%CI, 1.71–2.10), and 1.40 (95%CI, 1.30–1.51), respectively. The subgroup analysis showed that rs2439302 polymorphism was associated with higher TC risk in different ethnicities with OR > 1. The sensitivity analysis exhibited that the results were stable by omitting any included studies.

Conclusions

The study revealed that rs2439302 variants were associated with higher TC risk and may have a major influence on the choice of operative approach for patients with TC.

An Unexpected Tumor Reduction: Treatment with Olaparib Monotherapy in Heavily Pretreated BRCA2 Mutated Metastatic Pancreatic Cancer

PARP inhibitors are largely recognized as active drugs in BRCA-mutated breast and ovarian malignancies. In pancreatic ductal adenocarcinoma, the PARP inhibitor olaparib has recently been approved as maintenance treatment in patients with germline BRCA mutations reaching disease control after a platinum-based first line chemotherapy, proving significant benefit on progression free survival. On the other hand, little evidence is available regarding olaparib as single agent after progression with standard treatment in BRCA-mutated pancreatic ductal adenocarcinoma. A 61-year-old female patient harboring germline BRCA2 mutation was treated at our institution for a pancreatic ductal adenocarcinoma with lung and liver metastases. The patient received three previous lines of treatment with standard therapies, as follows: after the third line treatment failure, we started a further line of treatment with olaparib in off-label prescription. After the first two cycles, a CT scan documented partial response, with complete regression of lung metastases. The response was maintained after four cycles, with further response and clinical benefit. The radiologic and clinical response was maintained for 6 months. This case highlights the potential of olaparib as single agent after progression with standard treatment in BRCA-mutated pancreatic cancer.

PARP inhibition in treatment of pancreatic cancer

INTRODUCTION

Tumor control and survival of patients with metastatic pancreatic ductal adenocarcinoma (PDAC) has improved with more effective polychemotherapies. The identification of novel therapeutic targets is strongly needed in order to propose maintenance therapies that improve quality of life while maintaining tumor control.

AREAS COVERED

PDAC with mutations in homologous recombination repair genes such as BRCA are particularly sensitive to platinum agents. Recently, the potential role of poly(ADP-ribose) polymerase (PARP) inhibitors was suggested. The POLO study has shown that olaparib was efficient and well-tolerated as maintenance therapy in patients with germline BRCA1/2 mutation and a metastatic PDAC controlled after a platinum-based induction chemotherapy.

EXPERT OPINION

The demonstration of olaparib efficacy in patients with metastatic PDAC and BRCA germline mutation has paved the way for maintenance with a targeted therapy. Further studies are needed to assess; the potential role for PARPI in earlier forms of PDAC, those with somatic or more rare BRACness signatures, to overcome primary or secondary resistances to PARPi, and to combine them with other antitumoral agents.

The Unmet Needs of the Diagnosis, Staging, and Treatment of Gastrointestinal Tumors

New scientific insights in cancer biology and immunobiology have changed the clinical practice of medical oncology in recent years. The molecular stratification of solid tumors has led to improved clinical outcomes and is a key part in the diagnostic workup. Beyond mutational spectra (like Rat sarcoma [RAS] mutations or tumor mutational burden), the investigation of the immunological microenvironment has attracted more efforts. Especially as immunotherapies have changed the standard treatment for some solid tumors dramatically and have become an important part of routine oncology, also for gastrointestinal tumors. Still only a subgroup of patients benefits from immunotherapy in gastrointestinal tumors with prominent examples from colorectal, pancreatic or gastric cancer. Not only microsatellite instability as a marker for response to immunotherapy has shown its utility, there plenty of other approaches currently being investigated to better stratify and understand the microenvironment. But these insights have not translated into clinical utility. Reasons for this are limited technical capabilities for stratification and for coping with heterogeneity of tumor cells and the microenvironment as such. So the situation for gastrointestinal tumors has shown mainly progress for a subgroup of immunotherapy-receptive tumors (eg, microsatellite instability), but advances for the remaining majority have been in the area of stratification and combinatorial therapies, including approaches without chemotherapy. Molecular stratification (eg, B-Rapidly Accelerated Fibrosarcoma [BRAF] V600E mutation in colorectal cancer or NRG1 fusions in Kirsten-rat sarcoma (KRAS) Wild-Type Pancreatic Cancer) has clearly improved the possibilities for directed therapies, but there is a plethora of clinical situations where further developments are needed to improve patient care. Finding these areas and identifying the technical approach to unravel the complexities is the next decisive step. Here the recent advances are summarized and an outlook on possible diagnostic and treatment options in areas of unmet need is given with the context of new molecular imaging possibilities and cutting edge advances in nuclear medicine.

Genomic Methods Identify Homologous Recombination Deficiency in Pancreas Adenocarcinoma and Optimize Treatment Selection

PURPOSE

Genomic methods can identify homologous recombination deficiency (HRD). Rigorous evaluation of their outcome association to DNA damage response-targeted therapies like platinum in pancreatic ductal adenocarcinoma (PDAC) is essential in maximizing therapeutic outcome.

EXPERIMENTAL DESIGN

We evaluated progression-free survival (PFS) and overall survival (OS) of patients with advanced-stage PDAC, who had both germline- and somatic-targeted gene sequencing. Homologous recombination gene mutations (HRm) were evaluated: BRCA1, BRCA2, PALB2, ATM, BAP1, BARD1, BLM, BRIP1, CHEK2, FAM175A, FANCA, FANCC, NBN, RAD50, RAD51, RAD51C, and RTEL1 HRm status was grouped as: (i) germline versus somatic; (ii) core (BRCAs and PALB2) versus non-core (other HRm); and (iii) monoallelic versus biallelic. Genomic instability was compared using large-scale state transition, signature 3, and tumor mutation burden.

RESULTS

Among 262 patients, 50 (19%) had HRD (15% germline and 4% somatic). Both groups were analyzed together due to lack of difference in their genomic instability and outcome. Median [95% confidence interval (CI)] follow-up was 21.9 (1.4-57.0) months. Median OS and PFS were 15.5 (14.6-19) and 7 (6.1-8.1) months, respectively. Patients with HRD had improved PFS compared with no HRD when treated with first-line (1L) platinum [HR, 0.44 (95% CI: 0.29-0.67); P < 0.01], but not with 1L-non-platinum. Multivariate analysis showed HRD patients had improved OS regardless of their first-line treatment, but most had platinum exposure during their course. Biallelic HRm (11%) and core HRm (12%) had higher genomic instability, which translated to improved PFS on first-line platinum (1L-platinum) versus 1L-non-platinum.

CONCLUSIONS

Pathogenic HRm identifies HRD in patients with PDAC with the best outcome when treated with 1L-platinum. Biallelic HRm and core HRm further enriched benefit from 1L-platinum from HRD.

Advances in the Management of Pancreatic Adenocarcinoma

Outcomes in pancreatic cancer are improving. The beneficial effects being achieved with adjuvant and neoadjuvant therapies, and the recent application of molecular profiling, both germline and somatic, are collectively impacting survival. The NCCN Guidelines for Pancreatic Cancer urge clinicians to undertake “agnostic” germline testing for all persons with pancreatic cancer. Fit patients should also be considered for adjuvant therapy with modified FOLFIRINOX (leucovorin, 5-FU, irinotecan, oxaliplatin). Novel therapies that focus on DNA damage repair strategies are proving to be important, but notably several late-stage trials of several other approaches, reported in the last year, proved disappointing.

Precision medicine for gastrointestinal cancers: a conference report

As cancer management evolves into precision medicine national/international cancer meetings bring novel therapeutic approaches and potentially practice-changing results of clinical studies are presented. This year, the ASCO GI Symposium 2020 had also several updates from ongoing and finalized clinical trials. Although there were no groundbreaking results that impact the daily practice directly, several highly important data from ongoing studies were shared with the audience. In this report, the highlights of the ASCO GI Symposium 2020 are presented with a future perspective.