Systemic treatment in advanced phyllodes tumor of the breast: a multi-institutional European retrospective case-series analyses

BACKGROUND

We aimed at investigating outcome of systemic treatments in advanced breast PT.

METHODS

All cases of advanced breast PT treated with systemic treatments from 1999 to 2019, in one of the referral sarcoma centers involved in the study, were retrospectively reviewed.

RESULTS

56 female patients were identified. Median age was 52 (range of 25-76) years. Patients received a median number of 2 systemic treatments (range of 1-4). Best responses according to RECIST were 1 (3.7%) CR, 11 (40.7%) PR, 6 (22.2%) SD, 9 (33.3%) PD with anthracyclines plus ifosfamide (AI); 2 (16.7%) PR, 4 (33.3%) SD, 6 (50.0%) PD with anthracycline alone; 3 (18.8%) PR, 4 (25.0%) SD, 9 (56.3%) PD with high-dose ifosfamide given as a continuous infusion (HD-IFX); 3 (20.0%) SD, 12 (80.0%) PD with a gemcitabine-based regimen (with 2 patients not evaluable); 1 (8.3%) PR, 2 (16.7%) SD, 9 (75.0%) PD with trabectedin (with 1 patient not evaluable); 1 (16.7%) PR, 1 (16.7%) SD, 4 (66.7%) PD with tyrosine-kinase inhibitors (TKI). The median PFS were 5.7 (IQR 2.5-9.1) months with AI; 3.2 (IQR 2.2-5.0) months with anthracycline alone; 3.4 (IQR 1.4-6.7) months with HD-IFX; 2.1 (IQR 1.4-5.2) months with gemcitabine-based chemotherapy; 1.8 (IQR 0.7-6.6) months with trabectedin; 3.4 (IQR 3.1-3.8) months with TKI. With a median follow-up of 35.3 (IQR 17.6-66.9) months, OS from the start of first-line systemic treatment was 15.2 (IQR 7.6-39.6) months.

CONCLUSION

In this series of advanced PT (to our knowledge, the largest reported so far), AI was associated with a high rate of responses, however, with a median PFS of 5.7 months. Other systemic treatments were poorly active.

Epithelioid hemangioendothelioma, an ultra-rare cancer: a consensus paper from the community of experts

Epithelioid hemangioendothelioma (EHE) is an ultra-rare, translocated, vascular sarcoma. EHE clinical behavior is variable, ranging from that of a low-grade malignancy to that of a high-grade sarcoma and it is marked by a high propensity for systemic involvement. No active systemic agents are currently approved specifically for EHE, which is typically refractory to the antitumor drugs used in sarcomas. The degree of uncertainty in selecting the most appropriate therapy for EHE patients and the lack of guidelines on the clinical management of the disease make the adoption of new treatments inconsistent across the world, resulting in suboptimal outcomes for many EHE patients. To address the shortcoming, a global consensus meeting was organized in December 2020 under the umbrella of the European Society for Medical Oncology (ESMO) involving >80 experts from several disciplines from Europe, North America and Asia, together with a patient representative from the EHE Group, a global, disease-specific patient advocacy group, and Sarcoma Patient EuroNet (SPAEN). The meeting was aimed at defining, by consensus, evidence-based best practices for the optimal approach to primary and metastatic EHE. The consensus achieved during that meeting is the subject of the present publication.

•

This consensus paper provides key recommendations on the management of epithelioid hemangioendothelioma (EHE).

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Recommendations followed a consensus meeting between experts and a representative of the EHE advocacy group and SPAEN.

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Authorship includes a multidisciplinary group of experts from different institutions from Europe, North America and Asia.

Clinical prognostic factors in advanced epithelioid haemangioendothelioma: a retrospective case series analysis within the Italian Rare Cancers Network

Background

This multicentric, retrospective study conducted within the Italian Rare Cancer Network describes clinical features and explores their possible prognostic relevance in patients with advanced epithelioid haemangioendothelioma (EHE) started on surveillance.

Patients and methods

We collected data on adult patients with molecularly confirmed, advanced EHE consecutively referred at five sarcoma reference centres between January 2010 and June 2018, with no evidence of progressive disease (PD) and started on surveillance. Overall survival (OS) and progression-free survival (PFS) univariable and multivariable Cox analyses were performed. In the latter, due to the low number of cases and events, penalized likelihood was applied, and variable selection was performed using a random forest model.

Results

Sixty-seven patients were included. With a median follow-up of 50.2 months, 51 (76%) patients developed PD and 16 (24%) remained stable. PD at treatment start did not meet RECIST version 1.1 in 15/51 (29%) patients. The 3-year PFS and OS were 25.4% and 71.1%, respectively, in the whole population. Tumour-related pain (TRP) was the most common baseline symptom (32.8%), followed by temperature (20.9%), fatigue (17.9%), and weight loss (16.4%). Baseline TRP (P = 0.0002), development of TRP during follow-up (P = 0.005), baseline temperature (P = 0.002), and development of fatigue during follow-up (P = 0.007) were associated with a significantly worst PFS. An association between baseline TRP (P < 0.0001), development of TRP during follow-up (P = 0.0009), evidence of baseline serosal effusion (P = 0.121), and OS was recorded.

Conclusion

Because of the poor outcome observed in EHE patients presenting with serosal effusion, TRP, temperature, or serosal effusion, upfront treatment in this subgroup could be considered.

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Prognosis prediction in advanced EHE at presentation remains a challenge.

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This study explores the prognostic value of clinical and radiological features in advanced EHE patients on surveillance.

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Given their prognostic impact, symptoms and serosal effusion in EHE patients on surveillance should be regularly checked.

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In advanced EHE patients presenting with pain, temperature, or serosal effusion, upfront treatment could be considered.

Activity of axitinib in progressive advanced solitary fibrous tumour: Results from an exploratory, investigator-driven phase 2 clinical study

BACKGROUND

To explore the activity of axitinib in advanced solitary fibrous tumour (SFT).

PATIENTS AND METHODS

In this investigator-driven phase II study on axitinib in advanced and progressive SFT, patients received axitinib, 5 mg bis in day (BID), until progression or limiting toxicity. Pathologic diagnosis was centrally reviewed, distinguishing malignant SFT (M-SFT) and high-grade/dedifferentiated SFT (HG/D-SFT) subtypes. The primary end-point was the overall response rate (ORR) by Choi criteria (Choi). Secondary end-points were response by Response Evaluation Criteria in Solid Tumours (RECIST), progression-free survival (PFS) and overall survival (OS).

RESULTS

From April 2015 and October 2017, 17 eligible patients entered the study (metastatic: 17; SFT subtype: 13 M-SFT, 4 HG/D-SFT; prior treatment: 9 antiangiogenics, 5 cytotoxics). All patients were evaluable for response. The best Choi response was seven partial response (PR) (ORR, 41.2%), six stable disease (SD) and four progressions. Choi-ORR was 54% (7/13) when only M-SFTs were considered. Four of seven responsive patients were pretreated with pazopanib. No responses were detected in HG/D-SFT. Best RECIST response was one PR (5.9%), 14 SD and two progressions. Toxicity was as expected. Median Choi-PFS was 5.1 (interquartile range [IQR]: 2.5-14.8) months. Median Choi-PFS was 14.8 (IQR: 5.1-18.0) and 2.8 (IQR: 2.0-5.9) months for patients responsive and non-responsive by Choi, respectively (p = 0.0416). At a 14.4-month median follow-up, median OS was 25.3 months.

CONCLUSION

This study showed that axitinib is active in progressive advanced SFT. One-half of patients carrying the malignant variant of the disease responded, with a >12-month median progression arrest. Responses were better detected with Choi and seen even in patients resistant to other antiangiogenics. Tolerability was good.

Best practices for the management of local-regional recurrent chordoma: a position paper by the Chordoma Global Consensus Group

Chordomas are rare, malignant bone tumors of the skull-base and axial skeleton. Until recently, there was no consensus among experts regarding appropriate clinical management of chordoma, resulting in inconsistent care and suboptimal outcomes for many patients. To address this shortcoming, the European Society of Medical Oncology (ESMO) and the Chordoma Foundation, the global chordoma patient advocacy group, convened a multi-disciplinary group of chordoma specialists to define by consensus evidence-based best practices for the optimal approach to chordoma. In January 2015, the first recommendations of this group were published, covering the management of primary and metastatic chordomas. Additional evidence and further discussion were needed to develop recommendations about the management of local-regional failures. Thus, ESMO and CF convened a second consensus group meeting in November 2015 to address the treatment of locally relapsed chordoma. This meeting involved over 60 specialists from Europe, the United States and Japan with expertise in treatment of patients with chordoma. The consensus achieved during that meeting is the subject of the present publication and complements the recommendations of the first position paper.

Short, full-dose adjuvant chemotherapy (CT) in high-risk adult soft tissue sarcomas (STS): long-term follow-up of a randomized clinical trial from the Italian Sarcoma Group and the Spanish Sarcoma Group

BACKGROUND

To report on long-term results of a phase 3 trial comparing three versus five cycles of adjuvant chemotherapy (CT) with full-dose epirubicin+ifosfamide in high-risk soft tissue sarcomas (STS).

METHODS

Patients (pts) were randomized to receive three preoperative cycles of epirubicin 120 mg/m² and ifosfamide 9 g/m² (Arm A) or to receive the same three preoperative cycles plus two postoperative cycles (Arm B). Radiotherapy could be either delivered in the preoperative or in the postoperative setting. Non-inferiority of the primary end point, OS, was assessed by the confidence interval of the hazard ratio (HR; Arm A/Arm B) derived from Cox model.

RESULTS

Between January 2002 and April 2007, 164 pts were assigned to arm A and 164 to arm B. At a median follow-up (FU) of 117 months (IQ range 103-135 months), 123 deaths were recorded: 58 in Arm A and 65 in Arm B. Ten-year OS was 61% for the entire group of patients: 64% in Arm A and 59% in Arm B. The intention-to-treat analysis confirmed that three cycles were not inferior to five cycles (one-sided 95% upper confidence limit was 1.24). A per protocol analysis was consistent with these results. Pts with leiomyosarcoma and undifferentiated pleomorphic sarcoma (UPS) had the lowest, and the highest response rates, respectively. Consistently, Leiomyosarcoma and UPS had the worse and the best prognosis, respectively.

CONCLUSIONS

At a longer FU, the non-inferiority of three cycles of a full-dose conventional CT in comparison to five is confirmed. Response to therapy is also confirmed to be associated with better survival. This regimen is currently tested within an ongoing international trial against three cycles of a neoadjuvant histology-tailored CT (ClinicalTrials.gov Identifier: NCT01710176).

Long-term morbidity after multivisceral resection for retroperitoneal sarcoma

Background

More than 60 per cent of patients treated surgically for primary retroperitoneal sarcoma survive for at least 5 years. Extended surgical resection has been proposed for primary disease, but long-term morbidity data are lacking. A cross-sectional study was conducted to assess the long-term morbidity of patients undergoing surgery for retroperitoneal sarcoma.

Methods

Patients operated on between January 2002 and December 2011 were eligible for the study. Long-term morbidity was evaluated based on a semistructured clinical interview. Lower limb function was assessed by means of the Lower Extremity Functional Scale (LEFS), a self-report questionnaire with a total score ranging from 0 (low functioning) to 80 (high functioning). Pain was investigated by means of the Brief Pain Inventory – Short Form, with pain intensity scores reported on a scale from 0 (no pain) to 10 (worst pain).

Results

Some 243 patients underwent surgery, and 101 of 160 patients who were alive at the time of the investigation responded to the study invitation letter. Finally, 95 patients were enrolled in the study. Sensory impairment of the limbs was reported in 72 patients (76 per cent). The median LEFS score was 60 (i.q.r. 43–73). Mean scores for the pain intensity items varied from 1·23 to 2·68. In multivariable analysis, there was no difference in median levels of creatinine at survey between patients who did or did not undergo nephrectomy (difference between median values 13 (95 per cent c.i. −4 to 30) µmol/l; P = 0·170).

Conclusion

Severe chronic pain and lower limb motor impairment after multivisceral resection for retroperitoneal sarcomas are rare. Long-term renal function is not significantly impaired when nephrectomy is performed.

Rare Cancers Europe (RCE) methodological recommendations for clinical studies in rare cancers: a European consensus position paper

While they account for one-fifth of new cancer cases, rare cancers are difficult to study. A higher than average degree of uncertainty should be accommodated for clinical as well as for population-based decision making. Rules of rational decision making in conditions of uncertainty should be rigorously followed and would need widely informative clinical trials. In principle, any piece of new evidence would need to be exploited in rare cancers. Methodologies to explicitly weigh and combine all the available evidence should be refined, and the Bayesian logic can be instrumental to this end. Likewise, Bayesian-design trials may help optimize the low number of patients liable to be enrolled in clinical studies on rare cancers, as well as adaptive trials in general, with their inherent potential of flexibility when properly applied. While clinical studies are the mainstay to test hypotheses, the potential of electronic patient records should be exploited to generate new hypotheses, to create external controls for future studies (when internal controls are unpractical), to study effectiveness of new treatments in real conditions. Framework study protocols in specific rare cancers to sequentially test sets of new agents, as from the early post-phase I development stage, should be encouraged. Also the compassionate and the off-label settings should be exploited to generate new evidence, and flexible regulatory innovations such as adaptive licensing could convey new agents early to rare cancer patients, while generating evidence. Though validation of surrogate end points is problematic in rare cancers, the use of an updated notion of tumor response may be of great value in the single patient to optimize the use of therapies, all the more the new ones. Disease-based communities, involving clinicians and patients, should be regularly consulted by regulatory bodies when setting their policies on drug approval and reimbursement in specific rare cancers.

Preclinical and clinical evidence of activity of pazopanib in solitary fibrous tumour

BACKGROUND

To explore the activity of pazopanib in solitary fibrous tumour (SFT).

PATIENTS AND METHODS

In a preclinical study, we compared the activity of pazopanib, sorafenib, sunitinib, regorafenib, axitinib and bevacizumab in a dedifferentiated-SFT (DSFT) xenotransplanted into Severe Combined Immunodeficiency (SCID) mice. Antiangiogenics were administered at their reported optimal doses when mean tumour volume (TV) was 80 mm(3). Drug activity was assessed as TV inhibition percentage (TVI%). From May 2012, six consecutive patients with advanced SFT received pazopanib, on a national name-based programme. In one case sunitinib was administered after pazopanib failure.

RESULTS

In the xenograft model, pazopanib showed the lowest antitumour activity (21%TVI), while regorafenib was the most active (95%TVI). Sorafenib, bevacizumab, sunitinib were markedly active (78/70/65%TVI). Axitinib was marginally active (51%TVI). In the retrospective case-series, three patients carried malignant-SFT (MSFT), three DSFT. Best Response Evaluation Criteria in Solid Tumour (RECIST) responses were: three stable disease (SD), all MSFT, three progressive disease (PD), all DSFT, corresponding to one partial response (PR), two SD, three PD by Choi criteria. Median-progression-free survival was 3 months (range 1-15). In one patient, sunitinib was started after pazopanib failure, with a response.

CONCLUSIONS

In dedifferentiated-SFT xenograft pazopanib induced a marginal antitumour activity, while regorafenib appeared the most active and promising agent. When administered in patients, pazopanib showed a modest activity in terms of tumour growth stabilisation, observed only in non-dedifferentiated cases.

Guidelines for time-to-event end point definitions in sarcomas and gastrointestinal stromal tumors (GIST) trials: results of the DATECAN initiative (Definition for the Assessment of Time-to-event Endpoints in CANcer trials)†

BACKGROUND

The use of potential surrogate end points for overall survival, such as disease-free survival (DFS) or time-to-treatment failure (TTF) is increasingly common in randomized controlled trials (RCTs) in cancer. However, the definition of time-to-event (TTE) end points is rarely precise and lacks uniformity across trials. End point definition can impact trial results by affecting estimation of treatment effect and statistical power. The DATECAN initiative (Definition for the Assessment of Time-to-event End points in CANcer trials) aims to provide recommendations for definitions of TTE end points. We report guidelines for RCT in sarcomas and gastrointestinal stromal tumors (GIST).

METHODS

We first carried out a literature review to identify TTE end points (primary or secondary) reported in publications of RCT. An international multidisciplinary panel of experts proposed recommendations for the definitions of these end points. Recommendations were developed through a validated consensus method formalizing the degree of agreement among experts.

RESULTS

Recommended guidelines for the definition of TTE end points commonly used in RCT for sarcomas and GIST are provided for adjuvant and metastatic settings, including DFS, TTF, time to progression and others.

CONCLUSION

Use of standardized definitions should facilitate comparison of trials' results, and improve the quality of trial design and reporting. These guidelines could be of particular interest to research scientists involved in the design, conduct, reporting or assessment of RCT such as investigators, statisticians, reviewers, editors or regulatory authorities.

Activity of sunitinib in extraskeletal myxoid chondrosarcoma

BACKGROUND

Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft tissue sarcoma, marked by NR4A3 rearrangement. Herein we report on the activity of sunitinib in a series of 10 patients, strengthening what initially observed in two cases.

PATIENTS AND METHODS

From July 2011, 10 patients with progressive metastatic translocated EMC have been consecutively treated with sunitinib 37.5mg/day, on a named-use basis. In an attempt to interpret the activity of sunitinib in EMC, genotype/phenotype correlations were carried out by fluorescence in situ hybridization (FISH) analyses. Moreover, transcriptome, immunohistochemical and biochemical analyses of a limited set of samples were performed focusing on some putative targets of sunitinib.

RESULTS

Eight of 10 patients are still on therapy. Six patients had a Response Evaluation Criteria in Solid Tumours (RECIST) partial response (PR), two were stable, two progressed. Positron emission tomography (PET) was consistent in 6/6 evaluable cases. One patient underwent surgery after sunitinib, with evidence of a pathologic response. At a median follow-up of 8.5 months (range 2-28), no secondary resistance was detected. Median progression free survival (PFS) has not been reached. Interestingly, all responsive cases turned out to express the typical EWSR1-NR4A3 fusion, while refractory cases carried the alternative TAF15-NR4A3 fusion. Among putative sunitinib targets, only RET was expressed and activated in analysed samples.

CONCLUSIONS

This report confirms the therapeutic activity of sunitinib in EMC. Genotype/phenotype analyses support a correlation between response and EWSR1-NR4A3 fusion. Involvement of RET deserves further investigation.

Sporadic desmoid-type fibromatosis: a stepwise approach to a non-metastasising neoplasm--a position paper from the Italian and the French Sarcoma Group

Desmoid-type fibromatosis (DF) is a rare locally aggressive monoclonal proliferation of myofibroblasts lacking metastatic capacity. It may be observed in nearly every part of the body. Considering the variable clinical presentations, anatomic locations, and biologic behaviors, an individualized treatment approach is required. The pathogenesis of DF is not completely understood even if a high prevalence (∼85%) of CTNNB1 mutations discovered in sporadic DF underlies the importance of the Wnt/β-catenin pathway. No established and evidence-based approach for the treatment of this neoplasm is available as of today. Considering the unpredictable behavior and the heterogeneity of this disease, we propose a treatment algorithm approved by the French and the Italian Sarcoma Group, based on a front-line wait and see approach and subsequent therapy in the case of progression. A careful counseling at a referral center is mandatory and should be offered to all patients affected by sporadic DF from the time of their diagnosis.

Long-term follow-up of patients with GIST undergoing metastasectomy in the era of imatinib -- analysis of prognostic factors (EORTC-STBSG collaborative study)

BACKGROUND

Long-term complete remissions remain a rare exception in patients with metastatic gastrointestinal stromal tumors (GIST) treated with IM (imatinib). To date the therapeutic relevance of surgical resection of metastatic disease remains unknown except for the use in palliative intent.

PATIENTS AND METHODS

We analyzed overall survival (OS) and progression-free survival (PFS) in consecutive patients with metastatic GIST who underwent metastasectomy and received IM therapy (n = 239).

RESULTS

Complete resection (R0+R1) was achieved in 177 patients. Median OS was 8.7 y for R0/R1 and 5.3 y in pts with R2 resection (p = 0.0001). In the group who were in remission at time of resection median OS was not reached in the R0/R1 surgery and 5.1 y in the R2-surgery (p = 0.0001). Median time to relapse/progression after resection of residual disease was not reached in the R0/R1 and 1.9 years in the R2 group of patients, who were resected in response. No difference in mPFS was seen in patients progressing at time of surgery.

CONCLUSIONS

Our analysis implicates possible long-term survival in patients in whom surgical complete remission can be achieved. Incomplete resection, including debulking surgery does not seem to prolong survival. Despite the retrospective character and likely selection bias, this analysis may help in decision making for surgical approaches in metastatic GIST.

Some Lessons Learned from Imatinib Mesylate Clinical Development in Gastrointestinal Stromal Tumors

Imatinib mesylate is a molecular-targeted agent, shown to be effective in chronic myeloid leukemia and gastrointestinal stromal tumors (GIST). The latter may currently serve as a model on which speculating how the future of molecular-targeted therapy in solid tumors will be. So far, some lessons have been learnt. 1) Molecular-targeted therapy can be effective in the advanced disease setting, resulting in major tumor responses. 2) Patterns of tumor responses may be peculiar, radiologically and pathologically. 3) Anti-tumor activity may be highly predictable by assessing tumor molecular biology. 4) The methodology of clinical development of molecular-targeted agents may differ from standard chemotherapy in some respects, because, say, the preclinical rationale may be stronger, thus increasing the Bayesian prior probability of efficacy, or the optimal dose cannot be determined separately from the assessment of activity and efficacy. 5) Molecular-targeted agents will hardly remain "orphan drugs", if effective. 6) While an obvious impact on survival in the advanced disease setting has been clearly demonstrated, the biologic and clinical impact of molecular-targeted therapy still needs to be elucidated. Its eradicating capabilities, as well as the implications of secondary resistance, are to be understood. 7) Integrated, multimodality approaches, including surgery, may still be of value in the molecular-targeted therapy era.

Mode of action of trabectedin in myxoid liposarcomas

To elucidate the mechanisms behind the high sensitivity of myxoid/round cell liposarcoma (MRCL) to trabectedin and the suggested selectivity for specific subtypes, we have developed and characterized three MRCL xenografts, namely ML017, ML015 and ML004 differing for the break point of the fusion gene FUS-CHOP, respectively of type I, II and III. FUS-CHOP binding to the promoters of some target genes such as Pentraxin 3 or Fibronectin 1, assessed by chromatin immunoprecipitation, was strongly reduced in the tumor 24 h after the first or the third weekly dose of trabectedin, indicating that the drug at therapeutic doses causes a detachment of the FUS-CHOP chimera from its target promoters as previously shown in vitro. Moreover, the higher sensitivity of MRCL types I and II appears to be related to a more prolonged block of the transactivating activity of the fusion protein. Doxorubicin did not affect the binding of FUS-CHOP to target promoters. Histologically, the response to trabectedin in ML017 and ML015 was associated with a marked depletion of non-lipogenic tumoral cells and vascular component, as well as lipidic maturation as confirmed by PPARγ2 expression in western Blot. By contrast, in ML004 no major changes either in the cellularity or in the amount of mature were found, and consistently PPARγ2 was null. In conclusion, the data support the view that the selective mechanism of action of trabectedin in MRCL is specific and related to its ability to cause a functional inactivation of the oncogenic chimera with consequent derepression of the adypocytic differentiation.

Phase II study on lapatinib in advanced EGFR-positive chordoma

BACKGROUND

To report on a prospective, investigator-driven, phase II study on lapatinib in epidermal growth factor receptor (EGFR)-positive advanced chordoma patients.

PATIENTS AND METHODS

From December 2009 to January 2012, 18 advanced progressing chordoma patients entered this study (median age: 61 years; disease extent: metastatic 72% and locally advanced 28%). Epidermal growth factor receptor (EGFR) expression and activation were evaluated by immunohistochemistry and/or phospho-arrays, real-time polimerase chain reaction, fluorescence immunostaining. Fluorescence in situ hybridization analysis was also carried out. Patients received lapatinib 1500 mg/day (mean dose intensity = 1282 mg/day), until progression or toxicity. The primary study end point was response rate (RR) as per Choi criteria. Secondary end points were RR by Response Evaluation Criteria in Solid Tumor (RECIST), overall survival, progression-free survival (PFS) and clinical benefit rate (CBR; RECIST complete response + partial response (PR) + stable disease (SD) ≥ 6 months).

RESULTS

All patients were evaluable for response. Six (33.3%) patients had PR and 7 (38.9%) SD, as their best Choi responses, corresponding to RECIST SD in all cases. Median PFS by Choi was 6 [interquartile (IQ) range 3-8] months. Median PFS by RECIST was 8 (IQ range 4-12) months, with a 22% CBR.

CONCLUSIONS

This phase II study showed a modest antitumor activity of lapatinib in chordoma. The clinical exploitation of EGFR targeting in chordoma needs to be further investigated, both clinically and preclinically. Clinical trial Registration No: EU Clinical Trials Register trial no. 2009-014456-29.

Sunitinib malate in solitary fibrous tumor (SFT)

BACKGROUND

To report on sunitinib activity in a retrospective series of 35 solitary fibrous tumor (SFT) treated at a single institution.

PATIENTS AND METHODS

From April 2008, 35 patients with progressive advanced SFT (male/female: 20/15; mean age: 58 years; meningeal/extrameningeal: 6/29; locally advanced/metastatic: 15/20; prior chemotherapy: 25) were treated, on an individual use basis, with continuous-dosing sunitinib 37.5 mg/day. Platelet-derived growth factor receptor beta (PDGFRB) and vascular endothelial growth factor receptor 2 (VEGFR2) status were assessed by immunohistochemistry and, in a subgroup of patients, by real time PCR.

RESULTS

Thirty-one patients were assessable for response by RECIST (one early death; three early interruptions). Best responses were 2 partial response (PR), 16 stable disease, 13 progressive disease. A <30% decrease in size was observed in three patients. Fourteen of 29 patients assessable by Choi criteria had a PR. Median progression-free survival by RECIST was 6 months (range 1-22). In two of six patients, resistance to sunitinib was overcome by increasing sunitinib to 50 mg/day. PDGFRB and/or VEGFR2 were positive in all cases and not predictive of response; a less aggressive morphology corresponded to an increased response rate (53% PR by Choi in the malignant SFT, 20% PR in the pleomorphic/dedifferentiated SFT).

CONCLUSIONS

Sunitinib is active in SFT. Response can be long-lasting.

Adjuvant therapy in primary GIST: state-of-the-art

BACKGROUND

The management of primary gastrointestinal stromal tumours (GISTs) has evolved with the introduction of adjuvant therapy. Recently reported results of the SSG XVIII/AIO trial by the Scandinavian Sarcoma Group (SSG) and the German Working Group on Medical Oncology (AIO) represent a significant change in the evidence for adjuvant therapy duration. The objectives of this European Expert Panel meeting were to describe the optimal management and best practice for the systemic adjuvant treatment of patients with primary GISTs.

MATERIALS AND METHODS

A panel of medical oncology experts from European sarcoma research groups were invited to a 1-day workshop. Several questions and discussion points were selected by the organising committee prior to the conference. The experts reviewed the current literature of all clinical trials available on adjuvant therapy for primary GISTs, considered the quality evidence and formulated recommendations for each discussion point.

RESULTS

Clinical issues were identified and provisional clinical opinions were formulated for adjuvant treatment patient selection, imatinib dose, duration and patient recall, mutational analysis and follow-up of primary GIST patients. Adjuvant imatinib 400 mg/day for 3 years duration is a standard treatment in all patients with significant risk of recurrence following resection of primary GISTs. Patient selection for adjuvant therapy should be based on any of the three commonly used patient risk stratification schemes. R1 surgery (versus R0) alone is not an indication for adjuvant imatinib in low-risk GIST. Recall and imatinib restart could be proposed in patients who discontinued 1-year adjuvant imatinib within the previous 3 months and may be considered on a case-by-case basis in patients who discontinued within the previous year. Mutational analysis is recommended in all cases of GISTs using centralised laboratories with good quality control. Treatment is not recommended in an imatinib-insensitive D842V-mutated GIST. During adjuvant treatment, patients are recommended to be clinically assessed at 1- to 3-month intervals. Upon discontinuation, computed tomography scan (CT) scans are recommended every 3 to 4 months for 2 years when the risk of relapse is highest, followed by every 6 months until year 5 and annually until year 10 after treatment discontinuation.

CONCLUSIONS

Key points in systemic adjuvant treatment and clinical management of primary GISTs as well as open questions were identified during this European Expert Panel meeting on GIST management.

PALETTE: A randomized, double-blind, phase III trial of pazopanib versus placebo in patients (pts) with soft-tissue sarcoma (STS) whose disease has progressed during or following prior chemotherapy—An EORTC STBSG Global Network Study (EORTC 62072)

LBA10002

Background: Pazopanib, a multi targeted angiogenesis inhibitor, has demonstrated single-agent activity in pts with advanced STS. The efficacy and safety of pazopanib versus placebo as second or later line treatment were evaluated in pts with metastatic STS in a multi-center, international, double-blind, placebo-controlled phase III trial. Methods: Pts ≥18 years of age with angiogenesis inhibitor-naïve, histologically proven, metastatic STS, who failed at least one anthracycline containing regimen, could enter the study. They should have ≥1 measurable baseline lesion (per RECIST v1.0), WHO PS 0-1, adequate bone marrow, coagulation, hepatic and renal function, no poorly controlled hypertension, no bleeding diathesis, and no CNS involvement. The study has been conducted by EORTC and GSK in collaboration with 72 sarcoma centers worldwide. Pts were randomized 2:1 to receive either pazopanib 800 mg once daily or placebo until tumor progression, unacceptable toxicity, death, or pt’s request. Results: A total of 369 randomized pts (246 pazopanib, 123 placebo), median age of 56 years, participated in the study (EORTC 45 %, other 55%). Median duration of follow-up at clinical cut-off date is 15 months. The primary endpoint of progression-free survival (PFS) per independent review is significantly prolonged with pazopanib (median: 20 vs 7 weeks; HR=0.31, 95% CI 0.24-0.40 ; P<0.0001). The interim analysis for overall survival shows a statistically non-significant improvement of pazopanib vs placebo (median: 11.9 vs 10.4 months, HR=0.83, 95% CI 0.62-1.09). Main on-therapy grade 3-4 toxicities in the pazopanib vs placebo arm respectively: fatigue (13%, 6%), hypertension (7%, nil), anorexia (6%, nil), and diarrhea (5%, 1%). Similarly, thromboembolic events (grade 3-5 ) (3%, 2%), LVEF drop of >15% (8%, 3%). Median relative dose intensity of pazopanib was 768 mg daily. Conclusions: Pazopanib is an active drug in anthracycline pretreated metastatic STS pts with an increase in median PFS of 13 weeks.

Vatalanib for metastatic gastrointestinal stromal tumour (GIST) resistant to imatinib: final results of a phase II study

BACKGROUND

Vatalanib (PTK787/ZK 222584) inhibits a few tyrosine kinases including KIT, platelet-derived growth factor receptors (PDGFRs) and vascular endothelial growth factor receptors (VEGFRs). We report efficacy and safety results of vatalanib in advanced gastrointestinal stromal tumour (GIST) resistant to imatinib or both imatinib and sunitinib.

PATIENTS AND METHODS

Forty-five patients whose metastatic GIST had progressed on imatinib were enrolled. Nineteen (42.2%) patients had received also prior sunitinib. Vatalanib 1250 mg was administered orally daily.

RESULTS

Eighteen patients (40.0%; 95% confidence interval (CI), 25.7-54.3%) had clinical benefit including 2 (4.4%) confirmed partial remissions (PR; duration, 9.6 and 39.4 months) and 16 (35.6%) stabilised diseases (SDs; median duration, 12.5 months; range, 6.0-35.6+ months). Twelve (46.2%) out of the 26 patients who had received prior imatinib only achieved either PR or SD compared with 6 (31.6%, all SDs) out of the 19 patients who had received prior imatinib and sunitinib (P=0.324). The median time to progression was 5.8 months (95% CI, 2.9-9.5 months) in the subset without prior sunitinib and 3.2 (95% CI, 2.1-6.0) months among those with prior imatinib and sunitinib (P=0.992). Vatalanib was generally well tolerated.

CONCLUSION

Vatalanib is active despite its narrow kinome interaction spectrum in patients diagnosed with imatinib-resistant GIST or with imatinib and sunitinib-resistant GIST.

A phase II trial of sorafenib in relapsed and unresectable high-grade osteosarcoma after failure of standard multimodal therapy: an Italian Sarcoma Group study

PURPOSE

After standard multimodal therapy, the prognosis of relapsed and unresectable high-grade osteosarcoma is dismal and unchanged over the last decades. Recently, mitogen-activated protein kinases were shown to be activated in osteosarcoma specimens, suggesting, therefore, they are suitable targets for the multikinase inhibitor sorafenib. Thus, we explored sorafenib activity in patients with relapsed and unresectable osteosarcoma.

EXPERIMENTAL DESIGN

Patients > 14 years, progressing after standard treatment, were eligible to receive 400 mg of sorafenib twice daily until progression or unacceptable toxicity. The primary end point was progression-free survival (PFS) at 4 months. Secondary objectives were PFS, overall survival (OS), clinical benefit rate (CBR), defined as no progression at 6 months and safety. This nonrandomized phase II study used a Simon two-stage design. PFS and OS at 95% confidence intervals (95% CIs) were calculated by the Kaplan-Meier method. All tests were two sided.

RESULTS

Thirty-five patients were enrolled. PFS at 4 months was 46% (95% CI 28% to 63%). Median PFS and OS were 4 (95% CI 2-5) and 7 (95% CI 7-8) months, respectively. The CBR was 29% (95% CI 13% to 44%). We observed 3 (8%) partial responses (PRs), 2 (6%) minor responses (< 30% tumor shrinkage) and 12 (34%) stable diseases (SDs). For six patients (17%), PR/SD lasted ≥ 6 months. Noteworthy, tumor density reduction and [(18)F]2-fluoro-2-deoxy-d-glucose-positron emission tomography responses were observed among SD patients. Sorafenib was reduced or briefly interrupted in 16 (46%) patients and permanently discontinued in one (3%) case due to toxicity.

CONCLUSIONS

Sorafenib demonstrated activity as a second- or third-line treatment in terms of PFS at 4 months with some unprecedented long-lasting responses. Sorafenib, the first targeted therapy showing activity in osteosarcoma patients, deserves further investigations.

Sunitinib in advanced alveolar soft part sarcoma: evidence of a direct antitumor effect

BACKGROUND

The purpose of this study was to confirm sunitinib activity in alveolar soft part sarcoma (ASPS) and to report on new insights into the molecular bases thereof.

PATIENTS AND METHODS

From July 2007, nine patients with progressive metastatic ASPS received sunitinib 37.5 mg/day, within a named use program. Cryopreserved material was available for five naive patients, among whom three received sunitinib. Immunofluorescence (IF)/confocal microscopy, biochemical, and molecular/cytogenetic analyses were carried out, complemented by antiproliferative and activation assays in a short-term culture derived from one case.

RESULTS

All patients were eligible for response. Best RECIST response was partial response in five cases, stable disease in three, and progression in one. The median progression-free survival was 17 months. Positron emission tomography results were consistent. Two cases of interval progressions were recorded. Antiproliferative assays and biochemistry on short-term culture showed that sunitinib is able to markedly impair ASPS cells growth and switch-off PDGFRB. IF/confocal microscopy demonstrated coexpression and physical association between PDGFRB/vascular endothelial growth factor receptor 2 (VEGFR2) and RET/VEGFR2 in ASPS cells, which was validated by biochemistry. PDGFRB, RET, and MET ligand-dependent activation was confirmed.

CONCLUSIONS

We confirm the clinical efficacy of sunitinib in ASPS, mediated by PDGFRB, VEGFR2, and RET, which are all expressed in tumor cells. A direct antitumor effect was shown in a short-term cell culture.