Response to first line platinum-based chemotherapy in mismatch repair deficient (MMRd)/ microsatellite instability high (MSI-high) endometrial carcinoma

BACKGROUND

Around 15% of metastatic endometrial carcinoma (EC) are MMRd/MSI-H improving response to immune checkpoint inhibitors (ICI). So far, few data existed considering the chemotherapy (CT) sensitivity in MMRd/MSI-H EC, especially response to first-line platinum-based treatment.

PATIENTS AND METHODS

We performed a multicentric retrospective analysis reporting the response to first line platinum CT in MMRd/MSI-H EC patients. The primary endpoints were objective response rate (ORR) and progression-free survival (PFS) with first line platinum-based CT.

RESULTS

A total of 112 patients MMRd/MSI-H EC from 8 centers were identified. Median overall survival was 58.0 months (95% CI: 45.3-95.1). Among them, 78 patients received first line platinum CT in recurrent/metastatic setting. With a median follow up of 32.6 months (min: 0.03; max: 135.0), ORR and DCR (disease control rate) were 50% (95% CI: 38.5-61.5) and 68% (95% CI: 56.4-78.1), respectively. Median PFS and OS from first line platinum-based CT was 7.8 months (95% CI: 6.0-9.0) and 51.9 months (95% CI: 28.0-NE), respectively. Median PFS with ICI in second line (n = 48) was 10.7 months (95% CI: 3.4-NE) from ICI initiation.

CONCLUSION

ORR in first line metastatic MMRd/MSI-H EC is consistent with efficacy in an all comer metastatic EC population.

TCR Clonality and Genomic Instability Signatures as Prognostic Biomarkers in High Grade Serous Ovarian Cancer

PURPOSE

Immune infiltration is a prognostic factor in high-grade serous ovarian carcinoma (HGSC) but immunotherapy efficacy is disappointing. Genomic instability is now used to guide the therapeutic value of PARP inhibitors. We aimed to investigate exome-derived parameters to assess the tumor microenvironment according to genomic instability profile.

METHODS

We used the HGSC TCGA (the cancer genome atlas) dataset with genomic characteristics, including homologous recombination deficiency (HRD), copy number variant (CNV) signatures, TCR (T cell receptor) clonality and abundance of tissue-infiltrating immune and stromal cell populations. We then investigated the relationship with survival data.

RESULTS

In 578 HGSC patients, HRD status, CNV signature 7 and TCR clonality were associated with longer survival. The combination of high CNV signature 7 expression and HRD status or high CNV signature 3 expression and high TCR clonality was associated with a trend towards longer survival compared to each variable alone. Combining T cell infiltrate and TCR clonality improved the prognostic value compared to T cells infiltration alone. Prognostic value of TCR clonality was confirmed in an independent cohort.

CONCLUSIONS

TCR clonality is an emerging prognostic biomarker that improves T cell infiltrate information. Analysis of TCR clonality combined with genomic instability could be an interesting prognostic biomarker.

The cost-saving effect of centralized histological reviews with soft tissue and visceral sarcomas, GIST, and desmoid tumors: The experiences of the pathologists of the French Sarcoma Group

OBJECTIVE

This study examined the types of discordance occurring in the diagnosis of soft tissue and visceral sarcomas, gastrointestinal stromal tumors (GIST), and desmoid tumors, as well as the economic impact of diagnostic discrepancies.

METHODS

We carried out a retrospective, multicenter analysis using prospectively implemented databases performed on a cohort of patients within the French RRePS network in 2010. Diagnoses were deemed to be discordant based on the 2013 World Health Organization (WHO) classification. Predictive factors of discordant diagnoses were explored. A decision tree was used to assess the expected costs of two strategies of disease management: one based on revised diagnoses after centralized histological review (option 1), the other on diagnoses without centralized review (option 2). Both were defined based on the patient and the disease characteristics, according to national or international guidelines. The time horizon was 12 months and the perspective of the French National Health Insurance (NHI) was retained. Costs were expressed in Euros for 2013. Sensitivity analyses were performed using low and high scenarios that included ± 20% estimates for cost.

RESULTS

A total of 2,425 patients were included. Three hundred forty-one patients (14%) had received discordant diagnoses. These discordances were determined to mainly be benign tumors diagnosed as sarcomas (n = 124), or non-sarcoma malignant tumors diagnosed as sarcomas (n = 77). The probability of discordance was higher for a final diagnosis of desmoid tumors when compared to liposarcomas (odds ratio = 5.1; 95%CI [2.6-10.4]). The expected costs per patient for the base-case analysis (low- and high-case scenarios) amounted to €8,791 (€7,033 and €10,549, respectively) for option 1 and €8,904 (€7,057 and €10,750, respectively) for option 2.

CONCLUSIONS

Our findings highlight misdiagnoses of sarcomas, which were found to most often be confused with benign tumors. Centralized histological reviews are likely to provide cost-savings for the French NHI.

Impact of mutational status and other prognostic factors on survival in patients with advanced GIST treated with standard-dose imatinib (IM): Results from the BFR14 phase III trial of the French Sarcoma Group

10548

Background: Factors predicting progression free survival (PFS) and overall survival (OS) of patients (pts) with advanced GIST treated with 400 mg daily dose IM were investigated. As mutational status was a secondary objective of the BFR14 study, we wanted to evaluate the added value of these genomic profiles to conventional clinical prognostic factors. Methods: 434 pts were included in this prospective multicenter trial from June 2002 to July 2009. Prognostic factors for survival were investigated in the cohort where the mutational status was available. A multivariate Cox model including baseline characteristics statistically significant in univariate were included in a backward procedure to identify independent prognostic factors for PFS then OS. Results: Mutational analysis were available in 322 pts. Material was insufficient in 55 cases (12.5%), incomplete results were obtained in 39 pts (9%). There were 196 KIT genetic alterations (exon 11: 173 pts, exon 9: 22 pts, exon 17: 1 pt), 6 GIST with a PDGFRA mutations and 26 GIST WT. The analysis of prognostic factors was performed in all mutated and non-mutated GIST (221 pts) except for pts with a KIT exon 17 and PDGFRa mutation. As of January 2013, median follow-up was 73 months (m) (CI95%:63; 86), 147 progressions (67%) were notified and 84 deaths (38%) occurred. The median PFS and OS were 12.3 m (CI95%: 2.1;32.7) and 54.9 m (CI95%:16.5;83.8) for WT GIST, 12.6m (CI95%: 6.1;30.8) and 55m (CI95%:33.5;83.0) for KIT exon 9 and 39.4m (CI95%: 31.4;54.4) and not reached for KIT exon 11, respectively. An initial low tumour volume, gender (female), and CD34 positivity were the three independent prognostic factors of a higher PFS. A higher OS was independently predicted by PS, low neutrophil counts, KIT exon 11 alterations, normal lymphocyte count, lower tumor size and female’s gender. Conclusions: GIST pts harboring a KIT exon 11 mutations have the better outcome but the mutational status is not the only prognostic factor influencing the outcome of pts. The clinical (gender, PS, tumor size) and biological characteristics (lymphocytes and neutrophil counts) remain critical for OS.

Rechallenge with trabectedin in patients with locally advanced or metastatic soft tissue sarcoma following drug holiday: The experience of the French Sarcoma Group (FSG)

10062

Background: Trabectedin (T) is a marine-derived alkaloid used to treat advanced soft tissue sarcomas (STS) after ifosfamide and/or anthracyclins failure. Since then, the FSG evaluated the clinical benefit in re-administrating T after an initial hold, either medically indicated or upon patient’s request. Methods: Following an online request, clinical and histopathological data were collected from six centers of the FSG who declared to have rechallenged patients. Baseline data were collected and analyze will be used. Results: From 1999 to 2011, 49 pts with T drug holiday have been identified (26 male/ 23 female), with a median age of 50 y [23-75]. Most frequent histotypes were: myxoid liposarcoma (18, 36.7%), leiomyosarcomas (13, 26.5 %) and well-differentiated/dedifferentiated liposarcoma (9, 18%). WHO grade were 1 in 14 (29%), 2 in 19 (39%) and 3 in 5 (10%) pts respectively. Patients who had a maximum of 2, 3 or 4 therapeutic sequences (TS) with T (drug-holiday and rechallenge) were 41/49 ,7/49 and 1/49 respectively. Median number of cycles for 1, 2, 3 and 4 TS were 7 [3-21], 6 [2-30], 6 [2-9] and 6. Median total number of cycles was 15 [6-43]. Median duration of drug-holiday for 1, 2 and 3 TS were 11 [3-91], 7 [2-29] and 4 months [1-5]. Grade 3-4 toxicities incidence decreased with the number of TS (occurred in 36%, 29%, 14% and 0% of pts with 1, 2, 3 and 4 TS) as well as mean T dose per cycle (1.3 mg/m², 1.2 mg/m², 1.1 mg/m² and 1.1 mg/m² for TS 1, 2, 3, 4). Efficacy decreased with number of TS (Number of CR/PR/SD/PD were 1 (2%)/15 (31%)/33 (67%)/0 for TS1; 0/4 (8%)/29 (59%)/16 (3%) for TS2; 0/1 (14%)/2 (29%)/4 (57%) for TS3 and 0/0/0/1(100%) for TS4). Median overall survival was 5.0 y [2.7-7.3] since T introduction, and 1.5 y [0.1-4.8], 0.8 y [0.5-1.3] and 0.6 y following 2nd, 3rd and 4th T reintroduction respectively. Objective response after TS2 were seen in 4 cases of grade 1 sarcomas. Conclusions: Due to the lack of cumulative toxicities over time with T, its rechallenging in responding patients to T (no progression under T) have to be considered in advanced STS.

Adjuvant treatment of early-stage HER2+ elderly breast cancer patients: A retrospective, multicenter French study

636

Background: Trastuzumab (T) is the standard of care for the adjuvant treatment of early stage, HER2+ breast cancer (BC). However, few data are available for elderly HER2+ breast cancer patients in this setting. In this current study, the patterns of care for elderly HER2+ early stage BC in 7 French cancer centres was evaluated. Methods: Medical records of all consecutive early stage HER2+ BC patients over 70 years old treated between 2006 and 2011 among participating centres were retrospectively reviewed. Specific factors such as age, comorbidities, tumor stage, grade, ER/PR and HER2 status, treatment characteristics, follow-up and cardiotoxicity data were analysed. Results: One hundred and two patients were identified, median age 75.4 (range 70-95). Elderly patients presented mostly (57%) large tumors (pT ≥2), and positive lymph node involvement (n=61). Trastuzumab-based adjuvant treatment was administered in 62% of patients (n=63). 54% of patients (n=55) received adjuvant chemotherapy whereas five patients received neoadjuvant chemotherapy. Chemotherapy without T was administered in 2 additional patients. Anthracyclines (A)-Taxanes (Ta) combination-based chemotherapy was given in 27% of patients (n=16), whereas 38% received a Ta-based chemotherapy (n=23), 35% (n=19) an A-based chemotherapy. Five patients received single-agent T. Treatment delays for T were required in 37% of patients (n=23) among whom 15 and 8 permanently or temporarily stopped T, respectively. The most frequent reason for interrupting or delaying therapy was cardiotoxicity (n=12) as well as patients refusal (n=7). A ≥ 10% decrease in LVEF was observed in 18/63 (29%) of patients, among whom T was stopped in 12. After a median 33 months follow-up, the median progression-free survival was not reached in patients receiving T-based therapy. The 2 and 3-year PFS rate were 94 and 89.5%, respectively. Conclusions: In routine practice only 62% of elderly early stage HER2+ BC patients are treated with a neoadjuvant or adjuvant T-based regimen. However, less than 50% of all patients completed their therapy. A-based chemotherapy was administered in around 60% of treated patients, and could explain cardiotoxicity in this setting.

ET-743: a novel agent with activity in soft-tissue sarcomas

PURPOSE OF REVIEW

ET-743 (ecteinascidin-743, trabectedin, Yondelis) is a natural marine product that has shown clinical activity in sarcoma. This paper reviews the current knowledge on this compound.

RECENT FINDINGS

ET-743 interferes with several transcription factors, traps protein from the nucleotide-excision repair system, thus resulting in DNA damage, modulates gene expression, and blocks cells in the G2-M phase. In the clinical setting, after failure of standard treatment, ET-743 at 1.5 mg/m2 in 24 h continuous infusion every 21 days yielded an overall response rate close to 8% and stabilization rates of 30-40%, some lasting beyond 3 years. Leiomyosarcomas, liposarcomas, and synovial sarcomas may be the more sensitive histotypes. The major toxicities of ET-743 are hepatic--through biliary duct destruction--and hematologic. They are not cumulative and a significant number of patients may receive 12 courses or more. In a randomized Phase II study testing weekly ET-743 with treatment every 3 weeks, an improved progression-free survival rate was observed in the 3-weekly arm; the results of the follow-up Phase III trial should be available at the American Society of Clinical Oncology meeting of 2006. Phase I combination studies are in currently progress.

SUMMARY

ET-743 is a novel active drug for sarcoma which yields prolonged disease-free survival in subsets of patients.

[News of the year 2005 in sarcomas]

This year, the innovations were numerous in sarcomas. Important progress were accomplished in the search for predictive factors which make it possible to propose to the patient a personalized treatment with the therapeutic ones reduced in the event of good prognosis or on the contrary aggressive steps in the event of bad prognosis. These prognostic factors can be genetic or clinical. Progress were also accomplished in the clinical field with the research of the most adapted therapeutic strategies and of advanced in various drugs of chemotherapy in particular the ET-743. Lastly, research is active and of many ways are tested into preclinic with a detailed attention on the way of the angiogenesis.

ET‐743: A Novel Agent with Activity in Soft Tissue Sarcomas

Ecteinascidin-743 (ET-743) is a natural product derived from the marine tunicate Ectenascidia turbinate. ET-743 binds in the minor groove of DNA, blocks transcription factors activity, and traps protein from the nucleotide excision repair system, thus blocking cells in G2-M phase. ET-743 demonstrated cytotoxic activity at very low concentrations against sarcoma cell lines in pre-clinical studies. In several phase II clinical studies in patients with advanced sarcoma failing conventional doxorubicin- and ifosfamide-based chemotherapy, ET-743 delivered by continuous intravenous 24-hour infusion at a dose of 1,500 microg/m2 every 21 days yielded 8% overall response and 30%-40% stabilization rates for a clinical benefit rate close to 40%. Interestingly, long-term stabilizations over more than 3 years have been described. In vivo, ET-743 has a specific toxicity profile, the major toxicity of this product being hepatic, through biliary duct destruction, and hematologic. ET-743 has also been evaluated in first-line treatment for these patients. Finally, due to its original mode of action and the lack of cross-resistance with other chemotherapy agents, ET-743 was tested in a preclinical model in combination with other drugs. Synergy was reported in vitro with doxorubicin and cisplatin; phase I combination studies are in progress.