Neoadjuvant Pembrolizumab in Localized Microsatellite Instability High/Deficient Mismatch Repair Solid Tumors

PURPOSE

Pembrolizumab significantly improves clinical outcomes in advanced/metastatic microsatellite instability high (MSI-H)/deficient mismatch repair (dMMR) solid tumors but is not well studied in the neoadjuvant space.

METHODS

This is a phase II open-label, single-center trial of localized unresectable or high-risk resectable MSI-H/dMMR tumors. Treatment is pembrolizumab 200 mg once every 3 weeks for 6 months followed by surgical resection with an option to continue therapy for 1 year followed by observation. To continue on study, patients are required to have radiographic or clinical benefit. The coprimary end points are safety and pathologic complete response. Key secondary end points are response rate and organ-sparing at one year for patients who declined surgery. Exploratory analyses include interrogation of the tumor immune microenvironment using imaging mass cytometry.

RESULTS

A total of 35 patients were enrolled, including 27 patients with colorectal cancer and eight patients with noncolorectal cancer. Among 33 evaluable patients, best overall response rate was 82%. Among 17 (49%) patients who underwent surgery, the pathologic complete response rate was 65%. Ten patients elected to receive one year of pembrolizumab followed by surveillance without surgical resection (median follow-up of 23 weeks [range, 0-54 weeks]). An additional eight did not undergo surgical resection and received less than 1 year of pembrolizumab. During the study course of the trial and subsequent follow-up, progression events were seen in six patients (four of whom underwent salvage surgery). There were no new safety signals. Spatial immune profiling with imaging mass cytometry noted a significantly closer proximity between granulocytic cells and cytotoxic T cells in patients with progressive events compared with those without progression.

CONCLUSION

Neoadjuvant pembrolizumab in dMMR/MSI-H cancers is safe and resulted in high rates of pathologic, radiographic, and endoscopic response, which has implications for organ-sparing strategies.

A phase I study of intravenous artesunate in patients with advanced solid tumor malignancies

PURPOSE

The artemisinin class of anti-malarial drugs has shown significant anti-cancer activity in pre-clinical models. Proposed anti-cancer mechanisms include DNA damage, inhibition of angiogenesis, TRAIL-mediated apoptosis, and inhibition of signaling pathways. We performed a phase I study to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of intravenous artesunate (IV AS).

METHODS

Patients were enrolled in an accelerated titration dose escalation study with planned dose levels of 8, 12, 18, 25, 34 and 45 mg/kg given on days 1 and 8 of a 21-day cycle. Toxicities were assessed using the NCI CTCAE (ver. 4.0), and response was assessed using RECIST criteria (version 1.1). Pharmacokinetic (PK) studies were performed during cycle 1.

RESULTS

A total of 19 pts were enrolled, 18 of whom were evaluable for toxicity and 15 were evaluable for efficacy. DLTs were seen at dosages of 12 (1 of 6 patients), 18 (1 of 6) and 25 mg/kg (2 of 2), and were neutropenic fever (Gr 4), hypersensitivity reaction (Gr 3), liver function test abnormalities (Gr 3/4) along with neutropenic fever, and nausea/vomiting (Gr 3) despite supportive care. The MTD was determined to be 18 mg/kg. No responses were observed, while four patients had stable disease, including three with prolonged stable disease for 8, 10, and 11 cycles, for a disease control rate of 27%. PK parameters of AS and its active metabolite, dihydroartemisinin (DHA), correlated with dose.

CONCLUSION

The MTD of intravenous artesunate is 18 mg/kg on this schedule. Treatment was well tolerated. Modest clinical activity was seen in this pre-treated population. CLINICALTRIALS.

GOV IDENTIFIER

NCT02353026.

Beyond peptides and mAbs--current status and future perspectives for biotherapeutics with novel constructs

Biotherapeutics are attractive anti-cancer agents due to their high specificity and limited toxicity compared to conventional small molecules. Antibodies are widely used in cancer therapy, either directly or conjugated to a cytotoxic payload. Peptide therapies, though not as prevalent, have been utilized in hormonal therapy and imaging. The limitations associated with unmodified forms of both types of biotherapeutics have led to the design and development of novel structures, which incorporate key features and structures that have improved the molecules' abilities to bind to tumor targets, avoid degradation, and exhibit favorable pharmacokinetics. In this review, we highlight the current status of monoclonal antibodies and peptides, and provide a perspective on the future of biotherapeutics using novel constructs.

Comprehensive multiplatform biomarker analysis of 199 anal squamous cell carcinomas

Anal squamous cell carcinoma (ASCC) is a rare, HPV-associated malignancy typically diagnosed in early stages and definitively treated with chemoradiation. In situations where patients exhibit metastatic or recurrent disease, treatment options are severely limited. In this study, molecular alterations were identified that could be used to aid in therapeutic decisions for patients with metastatic or recurrent anal squamous cell carcinoma. Specimens from patients with this cancer were tested via a multiplatform profiling service (Caris Life Sciences, Phoenix, AZ) consisting of gene sequencing, protein expression by immunohistochemistry, and gene amplification with in situ hybridization. Utilizing these techniques, novel treatment strategies that could be explored were identified, including potential benefit with anti-EGFR therapies, immune checkpoint inhibitors, topoisomerase inhibitors, and taxanes. The frequency of overexpression of proteins that mark resistance to chemotherapeutic drugs, such as MRP1 (chemotherapy efflux pump), ERCC1 (resistance to platinum-based chemotherapy), and thymidylate synthase (resistance to fluoropyrimidines) were also identified, suggesting a lack of benefit. This multiplatform strategy could be explored for its potential to generate a personalized treatment selection for patients with advanced ASCC, provide a guide for future therapeutic development for this cancer, and be extended to other rare cancer types as well.

Phase II study of temozolomide and veliparib combination therapy for sorafenib-refractory advanced hepatocellular carcinoma

Purpose

To determine the antitumor efficacy and tolerability of combination temozolomide (TMZ) and veliparib (ABT-888) in patients with advanced, sorafenib-refractory hepatocellular carcinoma (HCC).

Methods

This single-arm phase II trial enrolled patients with pathologically confirmed, sorafenib-refractory HCC. All patients received 40 mg ABT-888 PO daily on days 1–7 and 150 mg/m² TMZ PO daily on days 1–5 of a 28-day cycle. The primary endpoint was objective response rate (ORR) at 2 months. Secondary endpoints included overall survival (OS), progression-free survival (PFS), and toxicity profile. Tumor response was assessed every 2 cycles using RECIST criteria, and toxicities were assessed using CTCAE v4.03.

Results

We enrolled 16 patients in the first phase of the trial, but the study was discontinued due to a poor ORR; only four patients (25 %) had SD after 2 cycles. Twelve patients (75 %) were taken off study after 2 months of treatment; 10 of these had disease progression. Two patients (13 %) were taken off study due to severe toxicity, and one patient (6 %) died from non-treatment-related liver failure. One patient had SD for 16 months, receiving 11 cycles of therapy before being taken off study. The most common grade 3 treatment-related toxicities included vomiting (n = 2), thrombocytopenia (n = 2), nausea (n = 1), and anemia (n = 1). The median PFS was 1.9 months, and median OS was 13.1 months.

Conclusion

The combination of TMZ and ABT-888 is well tolerated in patients with advanced HCC. However, the regimen failed to show survival benefit.

ClinicalTrials.gov Identifier

NCT01205828.

Electronic supplementary material

The online version of this article (doi:10.1007/s00280-015-2852-2) contains supplementary material, which is available to authorized users.

Development and Validation of a Novel Nomogram for Individualized Prediction of Survival in Cancer of Unknown Primary

PURPOSE

Prognostic uncertainty is a major challenge for cancer of unknown primary (CUP). Current models limit a meaningful patient-provider dialogue. We aimed to establish a nomogram for predicting overall survival (OS) in CUP based on robust clinicopathologic prognostic factors.

EXPERIMENTAL DESIGN

We evaluated 521 patients with CUP at MD Anderson Cancer Center (MDACC; Houston, TX; 2012-2016). Baseline variables were analyzed using Cox regression and nomogram developed using significant predictors. Predictive accuracy and discriminatory performance were assessed by calibration curves, concordance probability estimate (CPE ± SE), and concordance statistic (C-index). The model was subjected to bootstrapping and multi-institutional external validations using two independent CUP cohorts: V1 [MDACC (2017), N = 103] and V2 (BC Cancer, Vancouver, Canada and Sarah Cannon Cancer Center/Tennessee Oncology, Nashville, TN; N = 302).

RESULTS

Baseline characteristics of entire cohort (N = 926) included: median age (63 years), women (51%), Eastern Cooperative Oncology Group performance status (ECOG PS) 0-1 (64%), adenocarcinomas (52%), ≥3 sites of metastases (30%), and median follow-up duration and OS of 40.1 and 14.7 months, respectively. Five independent prognostic factors were identified: gender, ECOG PS, histology, number of metastatic sites, and neutrophil-lymphocyte ratio. The resulting model predicted OS with CPE of 0.69 [SE: ± 0.01; C-index: 0.71 (95% confidence interval: 0.68-0.74)] outperforming Culine/Seve prognostic models (CPE: 0.59 ± 0.01). CPE for external validation cohorts V1 and V2 were 0.67 (± 0.02) and 0.70 (± 0.01), respectively. Calibration curves for 1-year OS showed strong agreement between nomogram prediction and actual observations in all cohorts.

CONCLUSIONS

Our user-friendly CUP nomogram integrating commonly available baseline factors provides robust personalized prognostication which can aid clinical decision making and selection/stratification for clinical trials.

Prognosis Associated With CA19-9 Response Dynamics and Normalization During Neoadjuvant Therapy in Resected Pancreatic Adenocarcinoma

OBJECTIVE

To characterize associations between carbohydrate antigen 19-9 (CA19-9) dynamics during neoadjuvant therapy (NT) and survival for patients with pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND

Although normalization of CA19-9 during NT is associated with improved outcomes following PDAC resection, we hypothesize that CA19-9 dynamics during NT can improve prognostication.

METHODS

Characteristics for patients with PDAC undergoing NT (July 2011-October 2018) with ≥3 CA19-9 results (bilirubin<2mg/dL) were collected and grouped by CA19-9 dynamics. Nonproducers (<1 U/ml) were excluded, and normal was ≤35 U/ml. Postresection survival was compared among groups.

RESULTS

Of 431 patients, 166 had eligible CA19-9 values. Median baseline CA19-9 was 98 U/ml. Overall 2-year postresection recurrence-free survival (RFS) and overall survival (OS) were 37% and 63%, respectively. Patients with normalization (53%) had improved 2-year RFS (47% vs. 28%, P = 0.01) and OS (75% vs. 49%, P = 0.01). CA19-9 dynamics during NT were analyzed by shape, direction, and normalization creating response types ("A-B-C-D-E"). Type A was "Always" decreasing to normalization, B "Bidirectional" with eventual normalization, C "Consistently" normal, D any "Decrease" without normalization, and E "Elevating" without normalization. Types A and B responses were associated with the longest postresection 2-year RFS (51% and 56%) and OS (75% and 92%, respectively) whereas Types D and E had the worst outcomes. After adjusting for node-positivity, perineural invasion, and margin-positivity, CA19-9 response types were independently associated with both RFS and OS, and predicted outcomes are better than CA19-9 normalization alone (likelihood ratio test RFS P < 0.001, OS P = 0.01).

CONCLUSIONS

This novel A-B-C-D-E classification of CA19-9 dynamics during NT was associated with postresection outcomes more precisely than CA19-9 normalization alone.

A Phase I/II Study of Veliparib (ABT-888) in Combination with 5-Fluorouracil and Oxaliplatin in Patients with Metastatic Pancreatic Cancer

PURPOSE

Up to 17% of patients with pancreatic ductal adenocarcinoma (PDAC) harbor pathogenic (germline or somatic) mutations in a homologous recombination, DNA damage response and repair (HR-DDR) gene, such as BRCA1/2, or PALB2. Platinum-based chemotherapy, or treatment with PARP inhibitors are of particular benefit in these patients. However, there may be even greater benefit when platinums and PARP inhibitors are combined.

PATIENTS AND METHODS

We performed a single-arm, open-label, phase I/II study of the PARP inhibitor, veliparib, with 5-fluorouracil (no 5FU bolus) and oxaliplatin (FOLFOX) for patients with metastatic PDAC. Thirty-one patients were enrolled in a phase I dose escalation of veliparib (40 mg to 250 mg twice a day, days 1-7 of each 14-day cycle), to identify the recommended phase II dose (RP2D) of veliparib for the combination. Another 33 patients were enrolled in two parallel phase II trials to assess the objective response rate (ORR) in untreated or in previously treated patients. If available, germline or somatic testing was collected to identify pathogenic HR-DDR mutations.

RESULTS

The combination of veliparib and FOLFOX was tolerable at a RP2D of veliparib of 200 mg twice a day. The primary endpoint for both phase II cohorts was met, and the ORR overall was 26%. There was greater activity in platinum-naïve patients, and those who harbored a pathogenic HR-DDR mutation. Specifically, the ORR of HR-DDR mutated, platinum-naïve patients was 57%.

CONCLUSIONS

The combination of veliparib and FOLFOX was safe for patients with metastatic PDAC and showed promising activity particularly in patients with platinum-naïve disease that harbors a pathogenic HR-DDR mutation.

Prognostic Value of Nodal Response After Preoperative Treatment of Gastric Adenocarcinoma

Background: Pathologically positive lymph nodes (ypN+) after preoperative chemotherapy are associated with poor survival in patients with gastric cancer. Little is known about the association between response to preoperative therapy and the benefit of postoperative therapy. Methods: This retrospective cohort study of the National Cancer Database included patients with clinically node-positive (cN+) gastric cancer treated with preoperative therapy followed by surgery (2006-2014). Preoperative treatment modality was categorized as the inclusion of radiation therapy (RT) or chemotherapy alone. Pretreatment clinical and pathologic stages were used to determine pathologic treatment response rates. The association between overall risk of death and preoperative treatment, disease response, and adjuvant therapy use was evaluated using multivariable Cox regression. Results: Preoperative RT was used in 53.6% of 1,976 patients with cN+ gastric cancer, (74.3% cardia and 10.1% noncardia). The nodal response rate was 38.9% and was higher with RT than with chemotherapy alone (cardia, 46.0% vs 29.1%; P<.001; noncardia, 43.8% vs 31.9%; P=.06). Preoperative RT was associated with an approximate 2-fold increase in the odds of pathologic response compared with chemotherapy. Overall, use of adjuvant therapy was not associated with a decreased risk of death. A primary tumor response with residual nodal disease was not associated with survival (hazard ratio [HR], 1.03; 95% CI, 0.66-1.60). However, a nodal response with residual primary disease was significantly associated with survival (HR, 0.54; 95% CI, 0.44-0.65). Conclusions: More than one-third of node-positive gastric cancers showed pathologic nodal response with preoperative treatment. RT is associated with a higher response than chemotherapy. Patients with ypN+ disease have worse survival, regardless of whether they receive postoperative therapy. Future gastric cancer trials should evaluate the role of preoperative RT and individualize postoperative therapy use.

Efficacy of pembrolizumab in patients with advanced cancer of unknown primary (CUP): a phase 2 non-randomized clinical trial

BACKGROUND

Cancer of unknown primary (CUP) is an aggressive rare malignancy with limited treatment options. Data regarding clinical activity of immune checkpoint inhibitors in CUP is lacking. Therefore, we evaluated the efficacy of pembrolizumab, a programmed cell death-1 inhibitor, in patients with CUP.

METHODS

The study was designed as a phase 2 basket trial for independent rare tumor cohorts including CUP. Adult patients with CUP who had progressed on previous systemic therapy, performance status 0/1 and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST V.1.1) were eligible. Patients received pembrolizumab (200 mg) intravenously every 21 days. Twenty-nine patients were enrolled and treated between August 2016 and June 2020. The primary endpoint was non-progression rate (NPR) at 27 weeks (NPR-27) per immune-related RECIST. Key prespecified secondary endpoints were confirmed objective response rate (ORR), safety, duration of response (DoR), progression-free survival (PFS) and overall survival (OS). Pretreatment biopsies were examined for biomarkers of response (programmed cell death ligand-1 (PD-L1) expression and tumor infiltrating lymphocytes (TILs)).

RESULTS

Among 25 (of 29 enrolled) eligible and evaluable patients, 14 (56%) had poorly differentiated carcinoma. Patients received a median of two lines of therapy prior to enrollment. Median follow-up was 27.3 months. NPR-27 was observed in seven patients (28.0% (95% CI: 12.1 to 49.4)). ORR was 20.0% (95% CI: 6.8 to 40.7) with five patients achieving immune-related partial response with median DoR of 14.7 months (95% CI: 9.8 to 19.6). Median PFS and OS were 4.1 (95% CI: 3.1 to 5.1) and 11.3 (95% CI: 5.5 to 17.1) months, respectively. Treatment-related adverse events of any and grade ≥3 were seen in 19 (76%) and 4 (16%) patients, respectively. One (4%) patient had grade 3 immune-related acute kidney injury requiring treatment discontinuation. Neither PD-L1 nor TILs were associated with NPR-27. Both positive PD-L1 staining (44.4% vs 6.3%; p=0.040) and intense TIL infiltration (44.4% vs 6.3%; p=0.040) were associated with response.

CONCLUSION

Pembrolizumab showed encouraging efficacy in patients with CUP with acceptable safety profile.

TRIAL REGISTRATION NUMBER

NCT02721732.

Future directions in esophageal cancer therapy

Resection techniques for esophageal carcinoma continue to evolve, from endoscopic mucosal resection or endoscopic submucosal dissection for early stage disease to standard and robot-assisted minimally invasive esophagectomy as part of multimodal therapy for locally advanced disease. Though currently limited to assessing conduit perfusion and sentinel lymph nodes, embedded technology in the robotic surgical platform will likely play an expanded role during esophagectomy in the future. The use of targeted therapies, checkpoint inhibitors, engineered immune cell therapy, and cancer vaccines show promise in the treatment of systemic disease. Radiation therapy techniques are becoming increasingly sophisticated and they may play a more active role in stage IV disease in the future.

Gastric Adenocarcinoma: A Multimodal Approach

Despite its declining incidence, gastric cancer (GC) remains a leading cause of cancer-related deaths worldwide. A multimodal approach to GC is critical to ensure optimal patient outcomes. Pretherapy fine resolution contrast-enhanced cross-sectional imaging, endoscopic ultrasound and staging laparoscopy play an important role in patients with newly diagnosed ostensibly operable GC to avoid unnecessary non-therapeutic laparotomies. Currently, margin negative gastrectomy and adequate lymphadenectomy performed at high volume hospitals remain the backbone of GC treatment. Importantly, adequate GC surgery should be integrated in the setting of a multimodal treatment approach. Treatment for advanced GC continues to expand with the emergence of additional lines of systemic and targeted therapies.

Prognostic value of neoadjuvant treatment response in locally advanced rectal cancer

BACKGROUND

For locally advanced rectal cancer, response to neoadjuvant radiation has been associated with improved outcomes but has not been well characterized in general practice. The goals of this study were to describe disease response rates after neoadjuvant treatment and to evaluate the association between disease response and survival.

MATERIALS AND METHODS

Retrospective cohort study of patients aged 18-80 y with clinical stage II and III rectal adenocarcinoma in the National Cancer Database (2006-2012). All patients underwent radical resection after neoadjuvant treatment. Treatment responses were defined as follows: no tumor response; intermediate-T and/or N downstaging with residual disease; and complete-ypT0N0. Multivariable, multinomial regression was used to evaluate the association between neoadjuvant radiation use and disease response. Multivariable Cox regression was used to evaluate the association between disease response and overall risk of death.

RESULTS

Among 12,024 patients, 12% had a complete and 30% an intermediate response. Neoadjuvant chemotherapy alone was less likely to achieve an intermediate (relative risk ratio: 0.70 [0.56-0.88]) or a complete response (relative risk ratio: 0.59 [0.41-0.84]) relative to neoadjuvant radiation. Tumor response was associated with improved 5-y overall survival (complete = 90.2%, intermediate = 82.0%, no response = 70.5%; log-rank, P < 0.001). Complete and intermediate pathologic responses were associated with decreases in risk of death (hazard ratio: 0.40 [0.34-0.48] and 0.63 [0.57-0.69], respectively) compared to no response. Primary tumor and nodal response were independently associated with decreased risk of death.

CONCLUSIONS

Neoadjuvant radiation is associated with treatment response, and pathologic response is associated with improved survival. Pathologic response may be an early benchmark for the oncologic effectiveness of neoadjuvant treatment.

Role for Neoadjuvant Systemic Therapy for Potentially Resectable Pancreatic Cancer

Despite aggressive adjuvant management, a high percentage of patients who undergo appropriate surgical resection for pancreatic cancer will see their cancer recur and thus will not be cured. An important paradigm shift to achieve better outcomes has been therapy sequence, with neoadjuvant chemotherapy preceding surgery. Patients with a borderline resectable cancer, or patients with a resectable cancer but who have other high-risk features, are ideal candidates to consider for neoadjuvant chemotherapy. Among the high-risk features, a baseline elevated CA 19-9 concentration can be particularly useful, as its response trend during neoadjuvant chemotherapy can offer important insights into the prognosis after surgery. When selecting a neoadjuvant chemotherapy regimen, response data available for the use of FOLFIRINOX and gemcitabine and nabpaclitaxel in the metastatic setting support their use in this space. FOLFIRINOX is perhaps the preferred regimen, given its proven adjuvant benefit and possibly its superior tumor response rate; still, patient tolerance and thus ability to complete recommended treatment must be carefully considered. This review presents the evidence supporting neoadjuvant chemotherapy for resectable pancreatic cancer, the factors to consider when making such a recommendation, the selection of specific regimens, and our institutional approach using these tools.

Feasibility and value of genomic profiling in cancer of unknown primary: real-world evidence from prospective profiling study

Real-world evidence regarding the value of integrating genomic profiling (GP) in managing cancer of unknown primary (CUP) is limited. We assessed this clinical utility using a prospective trial of 158 patients with CUP (October 2016-September 2019) who underwent GP using next-generation sequencing designed to identify genomic alterations (GAs). Only 61 (38.6%) patients had sufficient tissue for successful profiling. GAs were seen in 55 (90.2%) patients of which GAs with US Food and Drug Administration-approved genomically matched therapy were seen in 25 (40.9%) patients. A change in therapy was recommended and implemented (primary endpoint of the study) in 16 (10.1%) and 4 (2.5%) patients of the entire study cohort, respectively. The most common reason for inability to implement the profiling-guided therapy was worsening of performance status (56.3%). Integrating GP in management of CUP is feasible but challenging because of paucity of tissue and aggressive natural history of the disease and requires innovative precision strategies.

Profile and potential of ixabepilone in the treatment of pancreatic cancer

The management of metastatic pancreatic adenocarcinoma is a challenge for medical oncologists because of both the aggressive nature of the disease and the relative paucity of effective systemic treatments with activity against this type of tumor. In the effort to discover new agents and combinations that may augment the therapeutic arsenal available for the management of this cancer, early phase clinical trials have been performed using ixabepilone, an epothilone B analog, with promising results. Targeting the microtubule system with certain taxanes in the management of pancreatic adenocarcinoma has been validated; ixabepilone also targets the microtubule system, interfering with it in an alternate manner from the taxane mechanism. Ixabepilone has demonstrated activity in cancers that have become taxane-resistant as well as those that never had any demonstrable taxane susceptibility. The available data for the use of ixabepilone in the management of pancreatic adenocarcinoma are limited but promising. Single-arm studies have demonstrated both clinical efficacy and tolerable toxicity for the use of ixabepilone as monotherapy. The trial data available for ixabepilone used as a part of combination therapy are similar: it has been paired with chemotherapy (carboplatin, irinotecan) and biologic therapy (dasatinib, sunitinib) at the Phase I level to treat solid tumors in general, again with tolerable side effects and a suggestion of benefit. A single Phase II study has evaluated combination therapy with ixabepilone in the management of patients with pancreatic cancer, pairing it with cetuximab with clinical benefit. Although these trials are promising with regard to addition of ixabepilone to the slim armamentarium for management of pancreatic cancer, further work is still to be done. Importantly, this work bears the burden of not only validating the clinical benefit of ixabepilone, but also of determining whether this benefit is enhanced in any way by combination therapy, and where ixabepilone fits in the sequence of management for patients with metastatic pancreatic cancer.

A phase I study of HER1, HER2 dual kinase inhibitor lapatinib plus the proteasome inhibitor bortezomib in patients with advanced malignancies

PURPOSE

This phase I trial evaluated the maximum tolerated dose, safety and preliminary efficacy of lapatinib, a HER1, HER2 dual kinase inhibitor plus bortezomib, a proteasome inhibitor, in adult patients with advanced malignancies.

METHODS

Patients were enrolled in a standard 3 + 3 design with lapatinib (L) 750, 1000, 1250 or 1500 mg daily, and bortezomib (B) 0.7, 1.0, 1.3 or 1.6 mg/m² for 3 weeks with 1 week off. Dose-limiting toxicities (DLT) were assessed during the first 28 days RESULTS: Fifteen patients received the combination of lapatinib and bortezomib in three different cohorts and ten were evaluable for DLT. There were no DLTs. Anorexia was the most common adverse event. Biomarker analysis showed upregulation of p27 expression with lapatinib and the combination. No tumor response was observed and thus the study was closed early.

CONCLUSION

The combination of lapatinib and bortezomib was well tolerated but no complete or partial tumor responses were observed at the dose levels tested. CLINICALTRIALS.

GOV IDENTIFIER

NCT01497626.

Continuum of care with anti-angiogenic therapies in metastatic colorectal cancer

Inhibition of tumor angiogenesis has emerged as an important therapeutic component in the management of metastatic colorectal cancer. Three anti-angiogenic agents are currently approved in this clinical setting: bevacizumab, ziv-aflibercept, and regorafenib. Bevacizumab, a monoclonal antibody that targets the angiogenesis-driving ligand vascular endothelial growth factor A (VEGF-A), is the only anti-angiogenic agent approved in first-line therapy for metastatic colorectal cancer, where it can be used in combination with intravenous 5-fluorouracil-containing chemotherapy regimens. In conjunction with second-line chemotherapies, bevacizumab also has anti-cancer activity, both for the management of metastatic colorectal cancer in patients who received it as a part of their first line therapy and for those who are naïve to it. Ziv-aflibercept also has demonstrated clinical activity in conjunction with the chemotherapeutic regimen FOLFIRI in the second line management of patients with metastatic colorectal cancer; it functions by binding VEGF-A to the vascular endothelial growth factor proteins VEGF-B and PIGF (placental growth factor). Regorafenib, which inhibits multiple tyrosine kinases, including the VEGF receptors, has proven clinical benefit in the management of patients with metastatic colorectal cancer refractory to all other therapies. For patients' whose cancers are refractory to all other therapies, there is also evidence for the use of bevacizumab with fluoropyrimidine monotherapy, but only in the bevacizumab-naïve patient subset. Presently, it is not clear if any one agent as more activity in a particular line of therapy than another, has greater efficacy when paired with a particular chemotherapy backbone, or if a particular patient subset is more likely to benefit from these agents. Given the present benefit and tolerance data, an anti-angiogenic agent should be considered in all lines of therapy in the management of metastatic colorectal cancer, with the evidence for the use of these agents in each specific line of therapy and in specific chemotherapeutic combinations driving agent selection.

Radiographic and Serologic Response to First-Line Chemotherapy in Unresected Localized Pancreatic Cancer

BACKGROUND

This study aimed to determine the clinical relevance of putative radiographic and serologic metrics of chemotherapy response in patients with localized pancreatic cancer (LPC) who do not undergo pancreatectomy. Studies evaluating the response of LPC to systemic chemotherapy have focused on histopathologic analyses of resected specimens, but such specimens are not available for patients who do not undergo resection. We previously showed that changes in tumor volume and CA 19-9 levels provide a clinical readout of histopathologic response to preoperative therapy.

METHODS

Our institutional database was searched for patients with LPC who were treated with first-line chemotherapy between January 2010 and December 2017 and did not undergo pancreatectomy. Radiographic response was measured using RECIST 1.1 and tumor volume. The volume of the primary tumor was compared between pretreatment and posttreatment images. The percentage change in tumor volume (%Δvol) was calculated as a percentage of the pretreatment volume. Serologic response was measured by comparing pretreatment and posttreatment CA 19-9 levels. We established 3 response groups by combining these metrics: (1) best responders with a decline in %Δvol in the top quartile and in CA 19-9, (2) nonresponders with an increase in %Δvol and in CA 19-9, and (3) other patients.

RESULTS

This study included 329 patients. Individually, %Δvol and change in CA 19-9 were associated with overall survival (OS) (P≤.1), but RECIST 1.1 was not. In all, 73 patients (22%) were best responders, 42 (13%) were nonresponders, and there were 214 (65%) others. Best responders lived significantly longer than nonresponders and others (median OS, 24 vs 12 vs 17 months, respectively; P<.01). A multivariable model adjusting for type of chemotherapy regimen, number of chemotherapy doses, and receipt of radiotherapy showed that best responders had longer OS than did the other cohorts (hazard ratio [HR], 0.35; 95% CI, 0.21-0.58 for best responders, and HR, 0.55; 95% CI, 0.37-0.83 for others).

CONCLUSIONS

Changes in tumor volume and serum levels of CA 19-9-but not RECIST 1.1-represent reliable metrics of response to systemic chemotherapy. They can be used to counsel patients and families on survival expectations even if pancreatectomy is not performed.

Cancer of Unknown Primary Presenting as Bone-Predominant or Lymph Node-Only Disease: A Clinicopathologic Portrait

BACKGROUND

Cancer of unknown primary (CUP) presenting as bone-predominant (BCUP) or lymph node-only disease (LNCUP) represents two clinically distinct subsets of nonvisceral CUP. These present a diagnostic challenge with a large differential of putative primary cancers and defy the "one-treatment-fits-all" approach.

MATERIALS AND METHODS

We identified patients with BCUP (n = 29) and LNCUP (n = 63) using a prospectively collected CUP database and tumor registry of patients seen at MD Anderson Cancer Center between 2001 to 2017. Clinicopathological characteristics, treatments, and outcomes were abstracted. A control group of non-BCUP/LNCUP cases (n = 443) from the database was used for comparison. Kaplan-Meier method was used to estimate overall survival and compared using log-rank test.

RESULTS

In this cohort, 64% and 60% patients had disseminated disease at diagnosis and 39% and 23% had Culine poor-risk disease in BCUP and LNCUP, respectively. Median overall survival (OS) for BCUP was 14.5 months and for LNCUP was 32.6 months. For BCUP, gemcitabine plus platinum was the most common initial chemotherapy (54%). For LNCUP, carboplatin plus paclitaxel was the most common initial chemotherapy (38%). Radiation was given to 74% of patients with BCUP and 37% of those with LNCUP. On multivariate analysis, poor-risk Culine group (hazard ratio [HR], 1.76; p < .001) and high neutrophil-to-lymphocyte ratio (HR, 2.38, p < .001) were associated with worse OS.

CONCLUSION

BCUP and LNCUP are rare subsets within CUP with varying prognosis. Poor-risk Culine group and high neutrophil-to-lymphocyte ratio are associated with poor survival. Select patients with limited metastases can have long-term survival with aggressive multimodality treatment. Careful clinicopathological review can facilitate chances of site-directed therapy.

IMPLICATIONS FOR PRACTICE

Cancer of unknown primary (CUP) rarely presents as bone-predominant (BCUP) or lymph node-only (LNCUP) disease. This article describes a cohort of each and compares with a larger CUP cohort. Patients with BCUP have unique issues with fractures and pain, often receiving radiation. Overall survival of 14.5 months was similar to a larger CUP comparison cohort. Patients with LNCUP had improved overall survival at 32.6 months, with longer survival in patients without disseminated disease. Culine poor-risk group and neutrophil-to-lymphocyte ratio were associated with worse overall survival. Tips regarding diagnosis and management of these rare malignant subsets are provided.

Exceptional Response to Systemic Therapy in Advanced Metastatic Gastric Cancer: A Case Report

Gastroesophageal adenocarcinomas represent one of the top five most common types of cancer worldwide. Despite significant advancement, it is still not known which first-line chemotherapy option is best matched to an individual patient. The vast advances in molecular biology have led to the discovery of many potential predictive biomarkers, such as HER-2 neu, thymidylate synthase (TS), excision repair cross-complementation group 1 (ERCC1), and topoisomerase-1 (TOPO1). These markers could allow us to select treatment based on an individual’s tumor profile, resulting in an improvement of outcome. Our report highlights two patients with metastatic gastric cancer that achieved an exceptional response with traditional therapy and provides insights into the future perspectives of molecular profile-directed chemotherapy.

Approach to the medical management of surgically resectable gastric cancer

The optimal adjuvant management of patients with resectable gastric cancer remains a therapeutic challenge. Although the benefit of adjuvant therapy for these patients is clearly established, recurrence and mortality rates remain high despite such treatment. Moreover, surgical comorbidities and treatment toxicities result in high rates of failure to complete treatment after surgery. Two divergent approaches to adjuvant treatment have emerged as standard: postoperative chemoradiotherapy and perioperative chemotherapy. Because these approaches have never been compared directly, recommendations for adjuvant treatment require multidisciplinary discussion. During this discussion, the characteristics of the symptoms, the histology, location, and stage of the tumor, and the feasibility of the patient's completing all recommended therapy may be considered. In our own practice, we favor perioperative chemotherapy for patients with asymptomatic, proximal, higher-stage disease and adjuvant chemoradiotherapy for patients with symptomatic, distal, lower-stage disease. Herein, we summarize the available data for approaches to the adjuvant treatment of gastric cancer, with special consideration of the characteristics of the patients enrolled in the various studies. We also describe how we developed our paradigm for recommending a particular approach to adjuvant treatment for each patient.

Utility of Established Prognostic Scoring Systems for Patients with Advanced Pancreatic Adenocarcinoma Enrolled in Immunotherapy-Based Early-Phase Clinical Trials

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy for which multiagent chemotherapy is the mainstay of treatment resulting in limited survival and symptomatic benefit. Treatment with immune checkpoint inhibitors (ICI) has proven effective in a growing number of solid tumors but has yet to show clinical benefit in patients with PDAC. Given the growing number of ICI-based clinical trials in development for patients with PDAC and lack of clinical benefit thus far with ICI-based therapies in these patients, we sought to (1) determine the outcomes of patients with PDAC treated with ICI-based therapies as part of an early phase clinical trial, (2) validate the utility of established prognostic scoring systems, and (3) identify novel prognostic factors in an attempt to better identify patients that would benefit from enrollment onto an ICI-based early phase clinical trial.

METHODS

We conducted a single-center retrospective analysis of patients with advanced PDAC who were treated with ICI-based therapy as part of an early-phase clinical trial.

RESULTS

Patients were only able to stay on study for a limited time due to disease progression and/or a change in performance status and had a poor overall survival. Established prognostic scoring systems were not effective in predicting outcomes in this patient population, but factors such as pre-treatment albumin neutrophil to lymphocyte ratio (NLC) may be helpful in patient selection.

CONCLUSIONS

This study underscores the need for larger studies to help identify patient and tumor intrinsic factors that predict response to ICI-based therapies in patients with PDAC.

Impact of KRAS mutations and co-mutations on clinical outcomes in pancreatic ductal adenocarcinoma

The relevance of KRAS mutation alleles to clinical outcome remains inconclusive in pancreatic adenocarcinoma (PDAC). We conducted a retrospective study of 803 patients with PDAC (42% with metastatic disease) at MD Anderson Cancer Center. Overall survival (OS) analysis demonstrated that KRAS mutation status and subtypes were prognostic (p < 0.001). Relative to patients with KRAS wildtype tumors (median OS 38 months), patients with KRASG12R had a similar OS (median 34 months), while patients with KRASQ61 and KRASG12D mutated tumors had shorter OS (median 20 months [HR: 1.9, 95% CI 1.2-3.0, p = 0.006] and 22 months [HR: 1.7, 95% CI 1.3-2.3, p < 0.001], respectively). There was enrichment of KRASG12D mutation in metastatic tumors (34% vs 24%, OR: 1.7, 95% CI 1.2-2.4, p = 0.001) and enrichment of KRASG12R in well and moderately differentiated tumors (14% vs 9%, OR: 1.7, 95% CI 1.05-2.99, p = 0.04). Similar findings were observed in the external validation cohort (PanCAN's Know Your Tumor® dataset, n = 408).