Immunotherapy in Breast Cancer: Current Practice and Clinical Challenges

Immunotherapy is currently approved for a subset of patients diagnosed with advanced triple negative breast cancer (TNBC), based on the phase III randomized controlled trial, IMpassion130. The anti-programmed cell death ligand-1 (PD-L1) immune checkpoint inhibitor atezolizumab combined with nanoparticle albumin-bound (nab)-paclitaxel is currently the standard first-line therapy in patients with metastatic TNBC who have a PD-L1-positive peritumoral immune infiltrate. Although this approval is limited to only a subset of patients, strategies to expand indications in breast cancer for this treatment modality are being extensively evaluated. A substantial need exists for the identification of patient characteristics, disease settings, immune markers, ideal partners for combination with immune checkpoint inhibitors, and the ideal sequence with traditional anticancer therapies. Additionally, in light of the results of the KEYNOTE-522 study of adjuvant pembrolizumab in TNBC, evaluation of immunotherapy in the early disease setting is a subject of great interest. This review article discusses current knowledge on immune checkpoint inhibitors in clinical practice, and provides an overview of a variety of markers evaluated to predict benefit of immunotherapy and of promising new strategies to enhance immune response and enable more patients to benefit from immunotherapy.

CDK4/6 Inhibitors in Hormone Receptor-Positive Metastatic Breast Cancer: Current Practice and Knowledge

Treatment paradigms in advanced hormone receptor (HR)-positive breast cancer were substantially transformed with cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) approval. The addition of these drugs to endocrine treatment profoundly improved progression-free and overall survival. Additionally, other important endpoints, such as the response rate, time to chemotherapy, and a delay in quality of life deterioration, were positively impacted by CDK4/6 inhibitors' addition to the treatment of advanced HR-positive breast cancer. This review article will summarize current knowledge on CDK4/6 inhibitors in clinical practice for advanced HR-positive metastatic breast cancer, as well as describe recent efforts to more precisely characterize mechanisms of sensitivity and resistance to these drugs, both on the molecular and clinical characterization level.

Management of metastatic cutaneous melanoma: updates in clinical practice

In recent years, several drugs have been approved for the treatment of patients with metastatic cutaneous melanoma, completely reshaping the landscape of this aggressive disease. Immune therapy with cytotoxic T-lymphocyte antigen 4 and programmed cell death-1 inhibitors yielded significant and durable responses, achieving long-term disease control in up to 40% of the patients. BRAF inhibitors (BRAFi), in combination with MEK inhibitors, also resulted in improved overall survival compared with single-agent BRAFi in patients with BRAFV600-mutated metastatic melanoma. The optimized sequencing and duration of treatment, however, is yet to be found. In this article, we thoroughly review current data and discuss how to best sequence the various treatment modalities available at present, based on four distinct clinical presentations commonly seen in clinic. In addition, we review treatment options beyond checkpoint inhibitors and targeted therapy, which may be required by patients failing such effective treatments.

Identification of risk in cutaneous melanoma patients: Prognostic and predictive markers

New therapeutic modalities for melanoma promise benefit in selected individuals. Efficacy appears greater in patients with lower tumor burden, suggesting an important role for risk-stratified surveillance. Robust predictive markers might permit optimization of agent to patient, while low-risk prognostic markers might guide more conservative management. This review evaluates protein, gene, and multiplexed marker panels that may contribute to better risk assessment and improved management of patients with cutaneous melanoma.

Algorithm for the management of metastatic cutaneous melanoma

Over the last 4 years, various drugs have been approved for the treatment of metastatic cutaneous melanoma. Ipilimumab, an anti-CTLA-4 inhibitor that stimulates antitumor immunity, was the first agent to improve overall survival both in first line and in previously treated patients. Ipilimumab results in long term disease control in approximately 20% of the patients. Vemurafenib was the first BRAF inhibitor (BRAFi) approved and also resulted in improved overall survival compared with dacarbazine in patients with BRAF mutated metastatic melanoma. More recently, another BRAFi, dabrafenib, and a MEK inhibitor, trametinib, were approved either alone or in combination as they each showed significant antitumor activity relative to dacarbazine and the combination appeared superior to dabrafenib monotherapy. The major feature of such tumor targeted therapy is its high response rate (40-70%) and the rapidity of the responses, resulting in prompt clinical improvement. However, unlike immunotherapy, targeted therapy does not result in long-term treatment free survival. In this paper, we discuss how best to integrate the currently available treatment options including high-dose interleukin-2 (HD IL-2), systemic chemotherapy, ipilimumab and tumor targeted therapy in various clinical scenarios.

Safety and efficacy of modified dose-attenuated FOLFIRINOX chemotherapy in patients over 65 years with advanced pancreatic adenocarcinoma

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Background: There is only limited data regarding efficacy and safety of FOLFIRINOX in elderly patients with advanced pancreatic adenocarcinoma. We aim to evaluate our experience with dose-reduced FOLFIRINOX in patients > 65 years-old. Methods: All patients > 65 years-old with biopsy-proven advanced pancreatic adenocarcinoma who received at least one cycle of modified dose-attenuatedFOLFIRINOX (no bolus FU and reduced dose of oxaliplatin and/or irinotecan) at our institution were identified. Results: Twenty-one consecutive patients (62% males) were reviewed. Median age was 67 (range 65-79). Grade 3/4 toxicities were reported in 7 (33%) patients ; the most common toxicities were anemia (62%), and nausea/vomiting (45%). Elevations in AST and/or ALT above the upper limit of normality were identified in 38%. No deaths due to toxicities were reported. Prophylactic granulocyte colony stimulator factor (G-CSF) was given in 16 (70 %) patients. Dose reductions were substantial with median reductions of 27,8 % (range 15 - 50%) for 5-FU, 27,1% (range 6-50%) for oxaliplatin and 25% (range 12-75%) for irinotecan. Median overall survival (OS) was 11,8 months (95% CI 10,2 - 13,3). Median progression free survival (PFS) was 6,9 months (95% CI 5,3 - 8,5). Conclusions: Modified dose-attenuated FOLFIRINOX is a reasonable option for elderly patients with advanced pancreatic adenocarcinoma. Adverse events were manageable and no deaths due to toxicity were reported. Median OS and PFS were similar to the pivotal phase III trial, demonstrating that dose-attenuated FOLFIRINOX may be beneficial to elderly patients.

Impact of first-line fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) for patients with advanced gastroesophageal adenocarcinoma: A retrospective analysis

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Background: Despite a large number of randomized trials, there is no consensus as to the best regimen for advanced gastroesophageal cancer. Combination therapy with docetaxel, cisplatin, and 5-FU has shown increased response rates, progression-free survival (PFS) and overall survival (OS), but at the cost of significant toxicity. Based on a small phase II study, FLOT has been adopted by some groups given its better toxicity profile. We aim at reporting our experience with this regimen Methods: Patients with unresectable advanced gastroesophageal adenocarcinoma who received FLOT (oxaliplatin 85 mg/m2, leucovorin 200 mg/m2, and fluorouracil 2600 mg/m2 as a 24h infusion in combination with docetaxel 50 mg/m2 on day 1 every 2 weeks) as first-line therapy at our institution were retrospectively evaluated. PFS and OS were estimated by the Kaplan-Meier method. Results: A total of 23 patients were reviewed, most of them with metastatic disease (60%). Median age was 56 years (range 26–76) and 74% were male. Median PFS and OS were 5,2 (95% CI 4,0-6,3) and 8,5 months (95% CI 4,4-12,6), respectively. Only 13%of the patients experienced prolonged PFS (>12 months). There were no deaths due to the treatment. Conclusions: Before FLOT could be adopted as a first-line regimen for metastatic gastroesophageal cancer, phase III trials are urgently needed comparing FLOT with more traditional regimens.

RAS mutations and their correlation with survival of patients with advanced pancreatic adenocarcinoma

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Background: The prognosis of pancreatic adenocarcinoma (PA) remains poor despite FOLFIRINOX and nab-paclitaxel-gemcitabine based chemotherapy. The epidermal growth factor receptor (EGFR) has a major role in pancreatic cancer carcinogenesis.The RAS status showed to be a predictive factor for response to anti-EGFR therapy in colon cancer. We aim to analyze the K-RAS and N-RAS status in PA and its prognostic impact. Methods: Retrospective analysis included 24 patients with metastatic (67%) or locally advanced (29%) PA at diagnosis (AEMOC, Brazil). K-RAS and N-RAS profile were performed by polymerase chain reaction and bidirectional sequencing (codons 12, 13, 61, 117, 146). The results were then analyzed in regards to overall survival (OS) and progression-free survival (PFS) in PA. Results: The sample showed: median age of 63 years (28-86), 62.5% male, 45.8% smoker, head site (67%), ductal (68%), and mild differentiation features (45%). The first-line therapy was FOLFIRINOX (62.5%) and gemcitabine (33.3%). The median PFS and OS were 6.5 and 13 months (mo), respectively. Nineteen patients (79.1%) presented mutation in K-RAS: four c.35G>A (G12D), four c.34G>C (G12R), four c.35G>T (G12V), three c.35G>C (G12A), one c.437C>T (A146V), and one c.34G>T (G12C). Mutation in N-RAS (c.38G>A (G13D) was detected in only one patient (4%). The only independent factor for survival was K-RAS status: the c.35G>A (G12D) polymorphism yielded worse PFS and OS when compared to non-c.35G>A (G12D) mutation: 3 vs 7 mo [HR 0.25, 95% CI, (0.04–1.63)] for PFS (p<0,0043) and 3.5 vs13 mo [HR 0.17, 95% CI, 0.01-1.58)] for OS (p<0,0001), respectively. Conclusions: K-RAS was the only prognostic factor for PFS and OS, with the polymorphism c.35G>A (G12D) being related to a worse prognostic. Further studies are necessary to better evaluate whether K-RAS and N-RAS status is prognostic and/or predictive factor.

Next-generation sequencing (NGS) in metastatic gastrointestinal cancer (mGIC) patients: Translation from sequence data into clinical practice

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Background: A considerable number of patients with mGIC progress after exhausting all approved standard therapies but maintain an adequate performance status and could be candidates for further treatment. We aim at reviewing our experience with the use of a NGS platform in refractory mGIC and its clinical utility. Methods: We retrospectively reviewed demographics, NGS results, and the suggested therapies received by patients undergoing NGS (Foundation Medicine, Cambridge, MA, USA): exonic sequencing of 236 genes and selective intronic sequencing from 19 genes for refractory mGIC. Co-primary endpoints were the percentage of patients with targeted therapy options uncovered by mutational profiling and the percentage of them who received genotype-directed therapy. Results: Samples from 32 patients were tested. Primary tumors consisted of colorectal adenocarcinoma (37,5%), pancreatic adenocarcinoma (31,2%), gastric adenocarcinoma (12,5%), cholangiocarcinoma (12,5%) and hepatocellular carcinoma (6%). Most patients (87,5%) were found to harbor potentially actionable genetic alterations involving mitogen-activated protein kinase (93,7%), phosphatidylinositol 3-kinase-AKT (18,7%), p53 (50%) and cell-cycle regulation (9%) pathways. Of the 6 patients who received the suggested targeted therapy, 4 achieved an objective response. Conclusions: Mutational profiling using a targeted NGS panel identified potentially actionable alterations in the majority of advanced gastrointestinal cancer patients. The assay provided clinical benefit in 12% of the patients.

Next-generation sequencing (NGS) in advanced pancreatic adenocarcinoma (PA): A Brazilian experience

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Background: Metastatic PA is a lethal malignancy with poor prognosis and limited therapeutic options. We hypothesized that a comprehensive next-generation sequencing (NGS) assay could identify novel therapy targets not routinely explored in PA patients. Methods: We included patients with advanced pancreatic adenocarcinoma (PA) with accessible lesion for biopsy. Paraffin-embedded tumor tissues were evaluated by the method of NGS (Foundation Medicine, Cambridge, MA, USA). Hybridization capture of 3,769 exons from 236 cancer-related genes and 47 introns of 19 genes commonly rearranged in cancer was applied to ≥ 50 ng of DNA extracted from 10 PA specimens and sequenced to high, uniform coverage. Genomic alterations (GAs), were characterized and reported for each patient sample. Actionable GAs were defined as those identifying anti-cancer targeted therapies either available on the market or in registered clinical trials. Results: A total of 10 PA patients were included. Median age was 56 years (range 31-79). All cases harbored at least one GA with a mean of 2.7 actionable GAs per tumor. The most common actionable GAs were KRAS (90%), PTCH1 (20%), STK11 (10%) and GNAS (10%). KRAS mutations potentially treatable with MEK-inhibitor were identified in 9 patients. However, none of them received a MEK-inhibitor. Activating STK11 point mutations not detectable by IHC/FISH, potentially targetable with m-Tor inhibitor therapies were identified in 1 patient, who received everolimus and had a long-lasting (> 6 months) partial response. Conclusions: NGS of PA was able to reveal genomic alterations that may be potentially responsive to available targeted therapy. We are just at the dawn of exploring this strategy and NGS can effectively contribute for increasing the understanding of the disease.

Role of second-line gemcitabine after FOLFIRINOX failure in advanced pancreatic adenocarcinoma: A retrospective analysis

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Background: Cancer of the exocrine pancreas is a highly lethal malignancy. Based on a phase III study, FOLFIRINOX regimen became the standard first-line treatment for patients with good performance status. However, the optimal management strategy for patients who fail initial FOLFIRINOX remains undefined. We aim at reporting our experience with single-agent gemcitabine as a second-line treatment for advanced pancreatic cancer patients who progressed on FOLFIRINOX. Methods: Patients with advanced exocrine pancreatic adenocarcinoma who received gemcitabine (1.000 mg/m² on days 1, 8 and 15 every 4 weeks) until disease progression, as second-line therapy after FOLFIRINOX failure at our institution were retrospectively evaluated. Progression-free survival (PFS) and overall survival (OS) were estimated by the Kaplan-Meier method. Results: A total of 20 patients were reviewed. Most of them (60%) had metastatic disease while 40% had locally advanced tumors. Median age was 60 years (range 43–74) and 80% were male. Eastern Cooperative Oncology Group (ECOG) performance status was 0 or 1 in 65% and 2 or 3 in 35% of the patients. Median time on prior FOLFIRINOX therapy was 5 months. Median PFS and OS with gemcitabine were 2,0 (95% CI 1,2-2,8) and 5,7 months (95% CI 3,9-7,4), respectively. There were no deaths due to the treatment. Conclusions: In this study, gemcitabine was a reasonable second-line treatment option for patients with advanced pancreatic adenocarcinoma. Phase III trials are urgently needed exploring the role of gemcitabine in the second-line setting.

Induction FOLFIRINOX followed by chemoradiation with capecitabine for unresectable locally advanced pancreatic cancer (LAPC): Preliminary data

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Background: FOLFIRINOX was found to have higher response rates and overall survival (OS) compared to gemcitabine-based regimens in the metastatic setting. However, the contribution of chemoradiotherapy to outcomes after FOLFIRINOX in LAPC remains uncertain. We aim at evaluating our experience with FOLFIRINOX followed by chemoradiation (IMRT) with capecitabine for patients with LAPC. Methods: Patients with unresectable LAPC who received induction FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan and oxaliplatin) followed by chemoradiation with capecitabine at our institution were screened and accrued at the time of radiotherapy and are being followed prospectively. Radiation technique consisted of IMRT with simultaneous integrated boost (SIB) - dose of 45 Gy (1.8Gy/day) to high-risk lymph nodes and 55 Gy (2.2Gy/day) to the primary tumor. Progression-free survival (PFS) and OS were estimated by the Kaplan-Meier method. Results: Fourteen patients (58% female) were included in the analyses. Median age at diagnosis of LAPC was 61 years (range 38-78). Median number of FOLFIRINOX cycles was 11 (range 4-13). With a median follow up fo 11.7 months, 43% of the patients have died. Median PFS and OS were 15.9 (95% CI 6.8 – 25.1) and 16.7 months (95% CI 10.9 – 22.4), respectively. There were no treatment-related deaths. Conclusions: Our data suggest that sequential treatment with FOLFIRINOX followed by chemoradiation with capecitabine is feasible and may offer promising PFS and OS among selected patients with LAPC. Randomized trials are urgently needed to assess the role of sequential treatment in this population.

Taxanes in the management of metastatic castration-resistant prostate cancer: efficacy and management of toxicity

Androgen deprivation is the therapy of choice in the majority of patients with metastatic prostate cancer. However, a state of castration resistance ultimately occurs after hormone therapy, thus defining metastatic castration-resistant prostate cancer (mCRPC). mCRPC has historically been considered a relatively chemoresistant tumor. However, due to its ability to improve survival and the quality of life in comparison with mitoxantrone, docetaxel has been established as the standard chemotherapeutic agent for first-line therapy since 2004. Moreover, recent results have shown that the novel taxane cabazitaxel is able to prolong the overall survival of patients with mCRPC previously treated with docetaxel. Even though these taxanes display a favorable toxicity profile, their routine use in clinical practice requires knowledge about the most frequent and distinct adverse events that may result from their administration.

Low-dose bevacizumab is effective in radiation-induced necrosis

Background

Radiation-induced necrosis is a complication of brain irradiation. Treatment options are limited.

Methods

The response to treatment with low-dose bevacizumab in 2 patients with radiation-induced necrosis was reported.

Results

Both patients with metastatic melanoma, aged 48 and 51 years, had significant symptomatic and radiological improvement with low-dose bevacizumab treatment. Doses as low as 5 mg/kg every 6 weeks and 7.5 mg/kg i.v. every 4 weeks were used and were highly effective.

Conclusions

Low-dose bevacizumab is a solid option in the management of edema associated with radiation necrosis.