Pegargiminase Plus First-Line Chemotherapy in Patients With Nonepithelioid Pleural Mesothelioma: The ATOMIC-Meso Randomized Clinical Trial

Importance

Arginine deprivation using ADI-PEG20 (pegargiminase) combined with chemotherapy is untested in a randomized study among patients with cancer. ATOMIC-Meso (ADI-PEG20 Targeting of Malignancies Induces Cytotoxicity-Mesothelioma) is a pivotal trial comparing standard first-line chemotherapy plus pegargiminase or placebo in patients with nonepithelioid pleural mesothelioma.

Objective

To determine the effect of pegargiminase-based chemotherapy on survival in nonepithelioid pleural mesothelioma, an arginine-auxotrophic tumor.

Design, Setting, and Participants

This was a phase 2-3, double-blind randomized clinical trial conducted at 43 centers in 5 countries that included patients with chemotherapy-naive nonepithelioid pleural mesothelioma from August 1, 2017, to August 15, 2021, with at least 12 months' follow-up. Final follow-up was on August 15, 2022. Data analysis was performed from March 2018 to June 2023.

Intervention

Patients were randomly assigned (1:1) to receive weekly intramuscular pegargiminase (36.8 mg/m2) or placebo. All patients received intravenous pemetrexed (500 mg/m2) and platinum (75-mg/m2 cisplatin or carboplatin area under the curve 5) chemotherapy every 3 weeks up to 6 cycles. Pegargiminase or placebo was continued until progression, toxicity, or 24 months.

Main Outcomes and Measures

The primary end point was overall survival, and secondary end points were progression-free survival and safety. Response rate by blinded independent central review was assessed in the phase 2 portion only.

Results

Among 249 randomized patients (mean [SD] age, 69.5 [7.9] years; 43 female individuals [17.3%] and 206 male individuals [82.7%]), all were included in the analysis. The median overall survival was 9.3 months (95% CI, 7.9-11.8 months) with pegargiminase-chemotherapy as compared with 7.7 months (95% CI, 6.1-9.5 months) with placebo-chemotherapy (hazard ratio [HR] for death, 0.71; 95% CI, 0.55-0.93; P = .02). The median progression-free survival was 6.2 months (95% CI, 5.8-7.4 months) with pegargiminase-chemotherapy as compared with 5.6 months (95% CI, 4.1-5.9 months) with placebo-chemotherapy (HR, 0.65; 95% CI, 0.46-0.90; P = .02). Grade 3 to 4 adverse events with pegargiminase occurred in 36 patients (28.8%) and with placebo in 21 patients (16.9%); drug hypersensitivity and skin reactions occurred in the experimental arm in 3 patients (2.4%) and 2 patients (1.6%), respectively, and none in the placebo arm. Rates of poststudy treatments were comparable in both arms (57 patients [45.6%] with pegargiminase vs 58 patients [46.8%] with placebo).

Conclusions and Relevance

In this randomized clinical trial of arginine depletion with pegargiminase plus chemotherapy, survival was extended beyond standard chemotherapy with a favorable safety profile in patients with nonepithelioid pleural mesothelioma. Pegargiminase-based chemotherapy as a novel antimetabolite strategy for mesothelioma validates wider clinical testing in oncology.

Trial Registration

ClinicalTrials.gov Identifier: NCT02709512.

Tumor treating fields affect mesothelioma cell proliferation by exerting histotype-dependent cell cycle checkpoint activations and transcriptional modulations

Although clinical antitumor activity of Tumor Treating Fields (TTFields) has been reported in malignant pleural mesothelioma (MPM) patients, the mechanisms behind the different selectivity displayed by the various MPM histotypes to this physical therapy has not been elucidated yet. Taking advantage of the development of well characterized human MPM cell lines derived from pleural effusion and/or lavages of patients' thoracic cavity, we investigated the biological effects of TTFields against these cells, representative of epithelioid, biphasic, and sarcomatoid histotypes. Growth inhibition and cell cycle perturbations caused by TTFields were investigated side by side with RNA-Seq analyses at different exposure times to identify pathways involved in cell response to treatment. We observed significant differences of response to TTFields among the cell lines. Cell cycle analysis revealed that the most sensitive cells (epithelioid CD473) were blocked in G₂M phase followed by formation of polyploid cells. The least sensitive cells (sarcomatoid CD60) were only slightly affected by TTFields with a general delay in all cell cycle phases. Apoptosis was present in all samples, but while epithelioid cell death was already observed during the first 24 h of treatment, sarcomatoid cells needed longer times before they engaged apoptotic pathways. RNA-Seq experiments demonstrated that TTFields induced a transcriptional response already detectable at early time points (8 h). The number of differentially expressed genes was higher in CD473 than in CD60 cells, involving several pathways, such as those pertinent to cell cycle checkpoints, DNA repair, and histone modifications. Our data provide further support to the notion that the antitumor effects of TTFields are not simply related to a non-specific reaction to a physical stimulus, but are dependent on the biological background of the cells and the particular sensitivity to TTFields observed in epithelioid MPM cells is associated with a higher transcriptional activity than that observed in sarcomatoid models.

Abstract 380: Tumor treating fields enhance cellular drug uptake in mesothelioma cell lines

Malignant pleural mesothelioma (MPM) is an aggressive malignancy with a 5-year survival rate of less than 10% and it remains a cancer lacking effective therapy options when tumors progress. The development of novel drug regimens for MPM treatment have been limited during the last two decades, with the exception of combinations including immune checkpoint inhibitors. In 2019, Tumor Treating Fields (TTFields) in combination with pemetrexed plus platinum-based chemotherapy were approved by the FDA for the first-line treatment of unresectable, locally advanced or metastatic, MPM. However, the mechanism of action of TTFields and their interaction with chemotherapeutic agents are not fully elucidated yet, thus a better knowledge may contribute to the design of more effective clinical trials for MPM patients. A panel of primary MPM cells was isolated from pleural effusion and/or lavages of patients’ thoracic cavity, before administration of therapeutic treatment, obtaining cell lines from the 3 subtypes of MPM. Epithelioid and sarcomatoid subtypes revealed different sensitivities to TTFields, with a stronger impact of the treatment on cell proliferation in the epithelioid subtype. This was associated with a higher modulation of transcription at different times of TTFields exposure, as demonstrated by RNA-seq analysis. Some of the genes modulated by the treatment encode membrane transport proteins, especially of the solute carrier family (SLC), in both sarcomatoid and epithelioid cells. This suggested a possible role of TTFields in cellular drug uptake and efflux. To test this hypothesis two cell lines, the sarcomatoid CD60 and the epithelioid CD473, have been treated with 150 kHz TTFields in combination with doxorubicin (DXR) following different schedules of treatment and the intracellular drug concentrations were assessed by HPLC measurements. TTFields exposure increased cellular uptake of DXR in both MPM models, but the effect was higher in CD473 epithelioid cells. After 24h of treatment with 1 µM DXR the amount of intracellular drug in sarcomatoid cells exposed to TTFields was almost twice that of the samples treated with DXR alone, while in epithelioid cells intracellular DXR concentration was almost four times higher than that found in TTFields untreated samples. This behavior might be ascribed to a different modulation of the gene coding for P-glycoprotein (ABCB1), which was markedly downregulated by TTFields treatment in epithelioid cells only. Similar experiments are in progress to test the impact of TTFields on cellular drug uptake in different combination schedules with other anticancer compounds. These data suggest that TTFields may increase the efficacy of drug treatments by enhancing the intracellular drug concentration and their possible confirmation by further experiments may represent an important rationale for the design of novel MPM therapies.

Citation Format: Monica Lupi, Rosy Amodeo, Lavinia Morosi, Laura Mannarino, Lara Paracchini, Sergio Marchini, Federica Grosso, Roberta Libener, Giovanni L. Ceresoli, Maurizio D'Incalci. Tumor treating fields enhance cellular drug uptake in mesothelioma cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 380.

Anetumab ravtansine versus vinorelbine in patients with relapsed, mesothelin-positive malignant pleural mesothelioma (ARCS-M): a randomised, open-label phase 2 trial

BACKGROUND

Few treatment options exist for second-line treatment of malignant pleural mesothelioma. We aimed to assess the antibody-drug conjugate anetumab ravtansine versus vinorelbine in patients with unresectable locally advanced or metastatic disease overexpressing mesothelin who had progressed on first-line platinum-pemetrexed chemotherapy with or without bevacizumab.

METHODS

In this phase 2, randomised, open-label study, done at 76 hospitals in 14 countries, we enrolled adults (aged ≥18 years) with unresectable locally advanced or metastatic malignant pleural mesothelioma, an Eastern Cooperative Oncology Group performance status of 0-1, and who had progressed on first-line platinum-pemetrexed chemotherapy with or without bevacizumab. Participants were prospectively screened for mesothelin overexpression (defined as 2+ or 3+ mesothelin membrane staining intensity on at least 30% of viable tumour cells by immunohistochemistry) and were randomly assigned (2:1), using an interactive voice and web response system provided by the sponsor, to receive intravenous anetumab ravtansine (6·5 mg/kg on day 1 of each 21-day cycle) or intravenous vinorelbine (30 mg/m2 once every week) until progression, toxicity, or death. The primary endpoint was progression-free survival according to blinded central radiology review, assessed in the intention-to-treat population, with safety assessed in all participants who received any study treatment. This study is registered with ClinicalTrials.gov, NCT02610140, and is now completed.

FINDINGS

Between Dec 3, 2015, and May 31, 2017, 589 patients were enrolled and 248 mesothelin-overexpressing patients were randomly allocated to the two treatment groups (166 patients were randomly assigned to receive anetumab ravtansine and 82 patients were randomly assigned to receive vinorelbine). 105 (63%) of 166 patients treated with anetumab ravtansine (median follow-up 4·0 months [IQR 1·4-5·5]) versus 43 (52%) of 82 patients treated with vinorelbine (3·9 months [1·4-5·4]) had disease progression or died (median progression-free survival 4·3 months [95% CI 4·1-5·2] vs 4·5 months [4·1-5·8]; hazard ratio 1·22 [0·85-1·74]; log-rank p=0·86). The most common grade 3 or worse adverse events were neutropenia (one [1%] of 163 patients for anetumab ravtansine vs 28 [39%] of 72 patients for vinorelbine), pneumonia (seven [4%] vs five [7%]), neutrophil count decrease (two [1%] vs 12 [17%]), and dyspnoea (nine [6%] vs three [4%]). Serious drug-related treatment-emergent adverse events occurred in 12 (7%) patients treated with anetumab ravtansine and 11 (15%) patients treated with vinorelbine. Ten (6%) treatment-emergent deaths occurred with anetumab ravtansine: pneumonia (three [2%]), dyspnoea (two [1%]), sepsis (two [1%]), atrial fibrillation (one [1%]), physical deterioration (one [1%]), hepatic failure (one [1%]), mesothelioma (one [1%]), and renal failure (one [1%]; one patient had 3 events). One (1%) treatment-emergent death occurred in the vinorelbine group (pneumonia).

INTERPRETATION

Anetumab ravtansine showed a manageable safety profile and was not superior to vinorelbine. Further studies are needed to define active treatments in relapsed mesothelin-expressing malignant pleural mesothelioma.

FUNDING

Bayer Healthcare Pharmaceuticals.

Treating disease progression with osimertinib in EGFR-mutated non-small-cell lung cancer: novel targeted agents and combination strategies

A precision medicine approach has been successfully applied in medical oncology for the treatment of non-small-cell lung cancer (NSCLC) through the identification of targetable driver molecular aberrations; activating mutations of epidermal growth factor receptor (EGFR) are the most common. Osimertinib, a third-generation, wild-type sparing, irreversible EGFR tyrosine kinase inhibitor (TKI), originally showed a striking activity after progression to first- and second-generation EGFR-TKIs when T790M resistance mutation was identified. Thereafter, upfront use of osimertinib became the standard of care based on overall survival benefit over first-generation TKIs erlotinib and gefitinib as reported in the FLAURA trial. For patients progressing on osimertinib, identification of resistance mechanisms is crucial to develop novel targeted therapeutic approaches. Moreover, innovative drugs or combination therapies are being developed for cases in which a specific resistance mechanism is not identifiable. In this review, the post-osimertinib treatment options for EGFR-mutated NSCLC are analyzed, with an outlook to ongoing clinical trials. An algorithm to guide clinicians in managing progression on osimertinib is proposed.

Abstract 1064: Antiproliferative effects of Tumor Treating Fields in human mesothelioma cell lines

Despite the increasing knowledge of the biology of malignant pleural mesothelioma (MPM), patients with this diagnosis still have a poor prognosis with a 5-year survival rate of lower than 10%. The effectiveness demonstrated by Tumor Treating Fields (TTFields) in combination with chemotherapy in preclinical experiments and in MPM patients (NCT02397928) affirms TTFields as a promising therapeutic tool. Knowledge of the mechanism of action of TTFields and its interaction with chemotherapeutic agents may contribute to the design of more effective clinical trials for MPM patients. A panel of primary MPM cells was isolated from pleural effusion and/or lavages of patients' thoracic cavity, before administration of therapeutic treatment, obtaining six cell lines from the 3 types of MPM cells: epithelioid CD473 and CD484, sarcomatoid CD60 and CD432, and biphasic CD487 and CD491. RNAseq analysis revealed that the transcriptional profiles of CD473 and CD60 cells were comparable with those derived from patient biopsies of the same histotype, representing clinically relevant MPM models. Antiproliferative effects induced by TTFields alone (1.12 V/cm; 150 KHz; for 96h duration) were studied in these MPM cell lines. Cell survival and cell cycle perturbations analyses during and after treatment were performed. Consistent with clinical observations, epithelioid MPM cells demonstrated greater sensitivity to TTFields than biphasic and sarcomatoid MPM cells. Cell cycle analysis revealed that the former cell type was blocked in G2M phase and was followed by formation of polyploid cells; while the latter cell types were only slightly affected by TTFields with a general delay in all cell cycle phases. Apoptotic cells were present in all treated samples, but while epithelioid and biphasic cell death was already observed during the first 24h of treatment, sarcomatoid cells needed to be treated for at least 24h before starting apoptotic pathways. The antiproliferative effect observed in epithelioid cells was persistent even after treatment cessation, whereas biphasic and sarcomatoid cells were able to reinitiate growth upon TTFields cessation. RNAseq experiments were performed in CD473 and CD60 cells at different times during TTFields application to explore transcriptional modifications that may explicate these varied MPM cell responses. Preliminary data suggested that TTFields induced a transcriptional response already detectable at earlier time points of treatment (8h; maximum effect at 24h). The number of differentially expressed genes was higher in CD473 relative to CD60 cells (1951 in CD473 and 336 in CD60 at 24h), involving several pathways, that need to be further investigated. These data demonstrate that TTFields induce specific effects on cell proliferation in varied subsets of mesothelioma cells and provide a mechanistic rationale for future therapies and combinations with other anticancer drugs for MPM treatment.

Citation Format: Monica Lupi, Federica Mirimao, Nicolò Panini, Greta Piazza, Lara Paracchini, Laura Mannarino, Sergio Marchini, Federica Grosso, Serena Penpa, Antonio Maconi, Giovanni L. Ceresoli, Maurizio D'Incalci. Antiproliferative effects of Tumor Treating Fields in human mesothelioma cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1064.

Salvage radiotherapy for oligo-progressive malignant pleural mesothelioma

OBJECTIVES

No standard treatment option is available for patients with unresectable malignant pleural mesothelioma (MPM) progressing after upfront chemotherapy. We aimed to explore the role of focal radiotherapy (FRT) as a treatment modality for oligo-progressive MPM.

MATERIALS AND METHODS

In this retrospective study, consecutive patients pretreated with ≥1 lines of chemotherapy were included. Oligo-progressive MPM was defined as an unresectable disease with radiological progression at ≤3 sites according to a chest-abdominal contrast-enhanced computed tomography. Patients were treated with either stereotactic body radiotherapy (SBRT, ≥5 Gy per fraction) or hypo-fractionated radiotherapy (hypoRT, <5 Gy per fraction). Time to further systemic therapy (TFST) and local control (LC) after FRT were the primary endpoints. Biologically effective dose (BED) was calculated using three different alpha/beta models (1.5 Gy, 3 Gy and 10 Gy).

RESULTS

From April 2006 to March 2019, 37 patients were treated on 43 pleural lesions; 16/37 (43 %) had undergone upfront multimodality treatment (MMT) including surgery. FRT was given in 22/37 (59.5 %) after one line of chemotherapy. SBRT was delivered for 26/43 lesions (60.5 %), hypoRT for 17/43 (39.5 %). Median TFST was 6 months (95 % CI 4.9-7.1). LC at 6 months and 1 year was 84 % and 76 %, respectively. Median TFST was longer in patients treated after 1 vs >1 line of chemotherapy (9 vs 4 months, p = 0.001) and in patients pretreated with MMT (6 vs 3 months, p = 0.021). Six-month LC was better in patients treated with a BED > 100 using alpha/beta 1.5 and 3. No ≥ G3 acute or late toxicities were reported.

CONCLUSION

FRT was feasible in selected patients with oligo-progressive MPM, allowing delay of further systemic therapies, with no severe toxicity. FRT was more effective when performed at progression after one line of systemic therapy. Our results suggest a radio-resistant behavior of MPM.

Lurbinectedin as second- or third-line palliative therapy in malignant pleural mesothelioma: an international, multi-centre, single-arm, phase II trial (SAKK 17/16)

BACKGROUND

Systemic second- and third-line therapies for malignant pleural mesothelioma (MPM) result in a median progression-free survival (mPFS) of <2 months and median overall survival (mOS) of 6-9 months. Lurbinectedin binds to the DNA of the regulatory region while inhibiting tumour-associated macrophage transcription. In early trials, encouraging outcomes occurred in patients (pts) with MPM treated with lurbinectedin. We aimed to generate lurbinectedin efficacy and safety data among pts with progressive MPM.

PATIENTS AND METHODS

Pts with progressing MPM treated with first-line platinum-pemetrexed chemotherapy with or without immunotherapy received lurbinectedin monotherapy. Treatment was given intravenously at 3.2 mg/m² dose every 3 weeks until progression or unacceptable toxicity. Using Simon's two-stage design, the primary endpoint, progression-free survival (PFS) at 12 weeks (PFS_12wks), was met if achieved by ≥21 pts (p0 ≤35% versus p1 ≥55%).

RESULTS

Forty-two pts from nine centres across Switzerland and Italy were recruited. Histology was epithelioid in 33 cases, sarcomatoid in 5, and biphasic in 4. Overall 10/42 (23.8%) underwent prior immunotherapy and 14/42 (33.3%) had progressed ≤6 months after first-line chemotherapy. At data cut-off PFS_12wks was met by 22/42 pts (52.4%; 90% confidence interval (CI): 38.7% to 63.5%; P = 0.015) with an mPFS of 4.1 months and mOS of 11.1 months. The best response was complete and partial remission observed in one patient each and stable disease in 20 pts. The duration of disease control was 6.6 months (95% CI: 5.2-7.4). No significant difference in PFS_12wks, mPFS, and mOS was recorded in epithelioid versus non-epithelioid cases and pts with prior immunotherapy versus those without. Similar mPFS but shorter mOS were observed among pts who progressed within ≤6 months after first-line chemotherapy. Lurbinectedin-related grade 3-4 toxicity was seen in 21 pts, mostly being neutropenia (23.8%) and fatigue (16.7%).

CONCLUSIONS

The primary efficacy endpoint was reached with acceptable toxicity. Lurbinectedin showed promising activity regardless of histology, prior immunotherapy, or outcome on prior treatment. CLINICALTRIALS.

GOV IDENTIFIER

NCT03213301.

Tumour Treating Fields in combination with pemetrexed and cisplatin or carboplatin as first-line treatment for unresectable malignant pleural mesothelioma (STELLAR): a multicentre, single-arm phase 2 trial

BACKGROUND

Tumour Treating Fields (TTFields) are a regional, antimitotic treatment for solid tumours, which is based on the delivery of low-intensity alternating electric fields. The aim of the STELLAR study was to test the activity of TTFields delivered to the thorax in combination with systemic chemotherapy for the front-line treatment of patients with unresectable malignant pleural mesothelioma.

METHODS

STELLAR was a prospective, single-arm, phase 2 trial done at 12 European academic and non-academic sites (five in Italy, three in Poland, one in France, one in Belgium, one in Spain, and one in the Netherlands) for treatment-naive patients with histologically confirmed unresectable malignant pleural mesothelioma. Patients were aged at least 18 years, had an Eastern Cooperative Oncology Group performance status of 0-1, and at least one measurable or evaluable lesion according to modified Response Evaluation Criteria in Solid Tumors for mesothelioma. Patients received continuous TTFields at a frequency of 150 kHz to the thorax and concomitant chemotherapy with intravenous pemetrexed (500 mg/m² on day 1) plus intravenous platinum (either cisplatin 75 mg/m² on day 1 or carboplatin area under the curve 5 on day 1) every 21 days for up to six cycles. Patients not progressing after completion of chemotherapy received TTFields as maintenance treatment until progression, patient or physician decision, or unacceptable toxic effects. The primary endpoint of the trial was overall survival. Survival analyses were done in the intention-to-treat population, and safety analyses were done in all patients who received at least 1 day of TTFields treatment. This trial is registered with ClinicalTrials.gov, NCT02397928.

FINDINGS

Between Feb 9, 2015 and March 21, 2017, 80 patients were enrolled in the study. Median follow-up was 12·5 months (IQR 7·4-16·6). Median overall survival was 18·2 months (95% CI 12·1-25·8). The most common grade 3 or worse adverse events were anaemia (nine [11%] patients), neutropenia (seven [9%]), and thrombocytopenia (four [5%]). Skin reaction was the only adverse event associated with TTFields and was reported as grade 1-2 in 53 (66%) patients, and as grade 3 in four (5%) patients. No treatment-related deaths were observed.

INTERPRETATION

The trial showed encouraging overall survival results, with no increase in systemic toxicity. TTFields (150 kHz) delivered to the thorax concomitant with pemetrexed and platinum was an active and safe combination for front-line treatment of unresectable malignant pleural mesothelioma. Further investigation in a randomised trial is warranted.

FUNDING

Novocure.

Meta-analysis of toxicity data in thoracic and abdominal malignancies from: Clinical trials in tumor treating fields

e14658

Background: Tumor Treating Fields (TTFields) are a non-invasive, loco-regional, antimitotic treatment modality, which has been approved for the treatment of glioblastoma (GBM) by the FDA. Mild-moderate localized dermatitis was reported in 52% of newly diagnosed GBM patients treated in the EF-14 [NCT0091640] phase 3 trial (with only 2% having Grade 3 skin toxicity). The toxicity of TTFields has been investigated in a number of pilot studies for malignancies located outside of the brain, and here we present a meta-analysis of toxicities reported in them. Methods: A total of 192 patients from four pilot clinical studies in the following malignancies were included: Advanced lung cancer, advanced pancreatic cancer, pleural mesothelioma and recurrent ovarian cancer. All patients received chemotherapy in addition to TTFields. Adverse events (AEs) and their association with the treatment were evaluated using CTCAE Criteria. Toxicities were reported as incidence by body system and MedDRA term out of the number of patients who received any amount of TTFields treatment. Results: The median age of patients was 63 (range: 44-78), 73 (49-81), 67 (27-78) and 60 (45-77) for EF-15 [NCT00749346], PANOVA [NCT01971281], STELLAR [NCT02397928] and INNOVATE [NCT02244502], respectively. The incidence of several low grade gastrointestinal (GI) toxicities was ≥5%: constipation (16%), diarrhea (14%), nausea (27%), vomiting (13%). None of the GI toxicities was associated with TTFields. Low grade general disorders such as asthenia (12%) and fatigue (18%) were common but not associated with TTFields. The incidence of arrhythmias was ≤2%. 58% of the patients had dermatological AEs, but only 6% had grade 3 dermatitis. 9% of patients had low grade pruritus. Conclusions: No new safety signals associated with TTFields were identified in this meta-analysis. The incidence of TTFields-related skin toxicity was similar to that reported in glioblastoma patients. The application of TTFields to the torso is safe. Clinical trial information: [NCT00749346], [NCT01971281], [NCT02397928], [NCT02244502].

Irradiation Fields and Doses in Glioblastoma Multiforme: Are Current Standards Adequate?

Aims and background

The optimum conventional radiotherapy in glioblastoma multiforme patients has not been clearly defined by prospective trials. To better characterize a standard radiotherapy in glioblastoma multiforme, the impact on survival of different fields and doses was analyzed in a retrospective single center series.

Methods

One hundred and forty-seven patients with glioblastoma multiforme, submitted to biopsy only (n = 15), subtotal (n = 48) or total resection (n = 82) and who completed the planned postsurgical radiotherapy, were considered. The median age was 57 years, the male/female ratio 1.5/1, and the performance status ≥70 in 76%. Whole brain irradiation, followed by a boost to partial brain, was used in 75 cases with a whole brain dose of 44–50 Gy (median, 46) and a partial brain dose of 56–70 Gy (median, 60 Gy). Partial brain irradiation alone was used in 72 patients with a dose of 56–70 Gy (median, 61 Gy). Ninety-eight patients received 56–60 Gy (median, 59 Gy) to partial brain whereas 49 patients received 61–70 Gy (median, 63 Gy).

Results

There was an almost significantly longer survival in patients irradiated to the partial brain alone with respect to those also receiving whole brain radiotherapy (P = 0.056). Doses <60 Gy significantly prolonged survival (P = 0.006). Multivariate analysis confirmed that the impact on survival of radiation dose was independent of age, performance status, extent of surgery, field of irradiation and the use of chemotherapy. The extent of irradiation field was not independently related to improved survival.

Conclusions

Our retrospective findings suggest that we reflect on the adequacy of the current standard irradiation parameters. Well-designed prospective trials are necessary to standardize the radiotherapy control group in patients with glioblastoma multiforme to be compared in phase III trials with innovative therapeutic approaches.

Improvement in survival and quality of life with new therapeutic agents in metastatic castration-resistant prostate cancer: comparison among the results

Androgen deprivation therapy is the mainstay of treatment for men affected by metastatic prostate cancer (PC). Unfortunately, nearly all patient will become resistant to the initial hormonal approach, developing a metastatic castration-resistant prostate cancer (mCRPC). For many years, chemotherapy with docetaxel has been the only established standard of care for men with mCRPC. Recent developments in the knowledge of the disease biology have shown that during the progression to the castrate status PC remains dependent on androgens and androgen receptor (AR) pathway. As a consequence, new agents like abiraterone acetate and enzalutamide have been rapidly developed and approved for clinical use. Other drugs with different mechanisms of action, such as sipuleucel-T, cabazitaxel, and radium-223 have shown to improve overall survival, symptom control and quality of life of mCRPC patients. However, the optimal sequencing and combination of these treatments are not defined yet. Studies on biomarkers for treatment selection, such as AR splice variants, are promising, but the initial data still need prospective validation on large patient series.

Prognostic factors in elderly patients with malignant pleural mesothelioma: results of a multicenter survey

BACKGROUND

The incidence of malignant pleural mesothelioma (MPM) in elderly patients is increasing. There are no specific guidelines for their management.

METHODS

The clinical records of elderly patients (⩾70 years old) with MPM referred from January 2005 to November 2011 to six Italian Centres were reviewed. Age, gender, histology, International Mesothelioma Interest Group (IMIG) stage, Eastern Cooperative Oncology Group Performance Status (ECOG-PS), Charlson Comorbidity Index (CCI) and treatment modalities were analysed and correlated to overall survival (OS).

RESULTS

In total, 241 patients were identified. Charlson Comorbidity Index was ⩾1 in 92 patients (38%). Treatment was multimodality therapy including surgery in 18, chemotherapy alone in 180 (75%) and best supportive care in 43 cases (18%). Chemotherapy was mainly pemetrexed based. Median OS was 11.4 months. Non-epithelioid histology (HR 2.32; 95% CI 1.66-3.23, P<0.001), age ⩾75 years (HR 1.44; 95% CI 1.08-1.93, P=0.014), advanced (III-IV) stage (HR 1.47; 95% CI 1.09-1.98, P=0.011) and CCI⩾1 (HR 1.38; 95% CI 1.02-1.85, P=0.034) were associated to a shorter OS. Treatment with pemetrexed was associated with improved OS (HR 0.40; 95% CI 0.28-0.56, P<0.001).

CONCLUSIONS

Non-epithelioid histology, age ⩾75 years, advanced IMIG stage and presence of comorbidities according to CCI were significant prognostic factors in elderly patients with MPM. Treatment with pemetrexed-based chemotherapy was feasible in this setting. Prospective dedicated trials in MPM elderly patients selected according to prognostic factors including comorbidity scales are warranted.

Vinorelbine in pemetrexed-pretreated patients with malignant pleural mesothelioma

BACKGROUND

Pemetrexed-platinum chemotherapy is the standard first-line treatment of unresectable malignant pleural mesothelioma (MPM). At progression, patients are generally selected to experimental trials, when available, or, in every-day clinical practice, they are offered second-line chemotherapy. The optimal treatment has not yet been defined. The aim of this retrospective, single-center study was to evaluate the activity and toxicity of vinorelbine administered to a consecutive series of pemetrexed-pretreated MPM patients.

METHODS

Vinorelbine 25 mg/m(2) was administered intravenously as a single agent on days 1, 8 every three weeks, either as second-line (2L) or further-line (>2L) therapy. Treatment was repeated for a maximum of 6 cycles, until progression, or unacceptable toxicity.

RESULTS

Fifty-nine patients were included in this analysis. Vinorelbine was given to 34 patients as 2L, and to 25 as > 2L treatment. The median age was 69 years (range 45-80). Forty-two patients (71.2%) had a good EORTC prognostic score. Partial response was observed in 9 (15.2%) cases, stable disease in 20 (33.9%). The overall disease control rate (DCR) was 49.1%. Median progression-free survival (PFS) and overall survival (OS) were 2.3 and 6.2 months, respectively. ECOG performance status (PS) (HR(0 vs. 1-2) 0.50; 95%CI: 0.3-0.8; p = 0.014) and PFS ≥ 6 months following first-line (FL) chemotherapy (HR(FL-PFS>6 ms vs. <6 ms) 0.50; 95%CI: 0.3-0.9; p = 0.031) were significantly associated to OS in multivariate analysis. No difference was observed in terms of DCR, PFS, and OS in relation to age, histology, sex, line of vinorelbine therapy, or response to FL treatment. Hematological toxicity was acceptable, with grade 3/4 neutropenia occurring in 5 (8.4%) patients, and there were no cases of febrile neutropenia. The main non-hematological toxicities were grade 2 fatigue in 17 (28.8%) and constipation in 7 (11.8%) patients.

CONCLUSIONS

Vinorelbine was moderately active in pemetrexed-pretreated MPM patients, with an acceptable toxicity profile, particularly in patients with ECOG-PS0 and FL-PFS ≥ 6 months.

Phase II study of pemetrexed and carboplatin plus bevacizumab as first-line therapy in malignant pleural mesothelioma

Background:

The aim of this open label phase II study (NCT00407459) was to assess the activity of the vascular endothelial growth factor (VEGF) inhibitor bevacizumab combined with pemetrexed and carboplatin in patients with previously untreated, unresectable malignant pleural mesothelioma (MPM).

Methods:

Eligible patients received pemetrexed 500 mg m⁻², carboplatin area under the plasma concentration–time curve (AUC) 5 mg ml⁻¹ per minute and bevacizumab 15 mg kg⁻¹, administered intravenously every 21 days for six cycles, followed by maintenance bevacizumab. The primary end point of the study was progression-free survival (PFS). A 50% improvement in median PFS in comparison with standard pemetrexed/platinum combinations (from 6 to 9 months) was postulated.

Results:

Seventy-six patients were evaluable for analysis. A partial response was achieved in 26 cases (34.2%, 95% CI 23.7–46.0%). Forty-four (57.9%, 95% CI 46.0–69.1%) had stable disease. Median PFS and overall survival were 6.9 and 15.3 months, respectively. Haematological and non-haematological toxicities were generally mild; however, some severe adverse events were reported, including grade 3–4 fatigue in 8% and bowel perforation in 4% of patients. Three toxic deaths occurred.

Conclusion:

The primary end point of the trial was not reached. However, due to the limitation of a non-randomised phase II design, further data are needed before drawing any definite conclusion on the role of bevacizumab in MPM.

Role of EGFR inhibitors in the treatment of central nervous system metastases from non-small cell lung cancer

Brain metastases (BM) are a common occurrence in patients with non-small cell lung cancer (NSCLC). Standard therapy options include whole brain radiotherapy and, in selected patients, surgery or stereotactic radiosurgery. The role of systemic treatment is controversial. There is a strong clinical rationale for the use of targeted therapies, because patients often have a poor performance status, and are not candidates for cytotoxic chemotherapy or radiotherapy, yet treatment is required to improve the extra-cranial disease. The efficacy of epidermal growth factor receptor (EGFR) inhibitors in the treatment of patients with BM from NSCLC has been reported mainly in case reports or small retrospective case series, with only a few prospective trials. Current evidence suggests that the use of EGFR tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib should be considered in patients with asymptomatic CNS involvement, when clinical characteristics suggest a high likelihood of response; these characteristics are adenocarcinoma histology, never-smoker status, female gender and East Asian ethnicity. Upfront therapy with EGFR TKIs should be strongly considered in asymptomatic patients harboring activating EGFR mutations. In symptomatic BM, radiotherapy (RT) remains the standard treatment. Based on currently available data, treatment with concurrent RT and EGFR TKIs should be investigated in experimental trials only.

An overview of neoadjuvant chemotherapy in the multimodality treatment of malignant pleural mesothelioma

Malignant Pleural Mesothelioma (MPM) is an aggressive tumour with poor prognosis and increasing incidence in industrialized countries because of the previous widespread exposure to asbestos fibres and to the long lag period from time of exposure and the diagnosis of the disease. MPM shows high refractoriety to systemic treatment, single-modality treatment was generally ineffective and did not achieve higher results than supportive care. The incidence of local and distant recurrences after surgery remains high and that was the reason for many centres to perform combined treatments. In the attempt of reducing the incidence of local recurrences, a multimodality approach with surgery followed by adjuvant radiotherapy was explored. Extrapleural pneumonectomy (EPP) allows higher doses of radiotherapy to the whole hemithorax by avoiding pulmonary toxicity and the results of this approach is a significant reduction of loco-regional relapses; although, extrathoracic metastasis represent a major problem in the management of the disease because of the impact on overall survival. The success with surgical resection after neoadjuvant chemotherapy in stage IIIA lung cancer has been the impetus for several groups to apply this strategy in MPM aiming at reducing the incidence of distant relapse after surgery. Platinum-based chemotherapy plus gemcitabine or pemetrexed for 3-4 cycles followed by surgery and postoperative high-dose radiotherapy showed the best results in terms of overall and progression free survival. This review will focus on the main clinical studies and overview the results of different chemotherapy regimens in the neoadjuvant treatment of MPM.

Second-line chemotherapy in malignant pleural mesothelioma: results of a retrospective multicenter survey

The pemetrexed-cisplatin chemotherapy is standard of care in first-line (FL) treatment of malignant pleural mesothelioma (MPM). The second-line (SL) chemotherapy is considered, but the optimal treatment has not been defined yet. The aim of this study was to evaluate the clinical outcomes of SL-therapy in a series of MPM-patients included in a retrospective multicenter database. Clinical records of MPM-patients who received SL-treatment from 1996 to 2008 were reviewed. Study endpoints were response, overall-survival (OS), and progression-free-survival (PFS) for SL, stratified for patient characteristics, FL-outcomes, and type of SL. Out of 423 patients, 181 with full clinical data were identified. Patients' characteristics: median-age 64 years (range: 36-85); male gender 115 (63.5%); good EORTC-score 109 (60.2%); epithelial histology 135 (74.6%). After FL, 147 (81.2%) patients achieved disease-control (DC) and 45 had a time-to-progression≥12 months (TTP≥12). After SL, 95 patients (52.6%) achieved DC (21 response; 74 stable-disease); median PFS and OS were 4.3 and 8.7 months, respectively. According to multivariate analysis, DC after SL-therapy was significantly related to pemetrexed-based treatment (OR: 2.46; p=0.017) and FL-TTP≥12 (OR: 3.50; p=0.006). PFS was related to younger age (<65 years) (HR: 0.70; p=0.045), ECOG-PS0 (HR: 0.67; p=0.022), and FL-TTP≥12 (HR: 0.45; p<0.001). OS was significantly related to ECOG-PS0 (HR: 0.43; p<0.001) and to FL-TTP≥12 (HR: 0.54; p=0.005). In pemetrexed pre-treated patients, re-treatment with a pemetrexed/platinum combination significantly reduced the risk-of-death than pemetrexed alone (HR: 0.11; p<0.001). In conclusion, SL-chemotherapy seems to be active in MPM-patients, particularly in younger patients with ECOG-PS0 and prolonged TTP after FL-pemetrexed-based chemotherapy. In selected patients, re-challenge with pemetrexed-based regimens, preferentially associated with platinum-compound, appears to be an option for SL-setting. Considering the important limitations of this study, due to retrospective nature and the possible selection bias, prospective clinical trials are warranted to clarify these issues.

Advances in the biology of malignant pleural mesothelioma

Malignant pleural mesothelioma is a highly aggressive cancer with a very poor prognosis. Although the mechanism of carcinogenesis is not fully understood, approximately 80% of malignant pleural mesothelioma can be attributed to asbestos fiber exposure. This disease is largely unresponsive to conventional chemotherapy or radiotherapy, and most patients die within 10-17 months of their first symptoms. Currently, malignant pleural mesothelioma therapy is guided by clinical stage and patient characteristics rather than by the histological or molecular features of the tumor. Several molecular pathways involved in malignant pleural mesothelioma have been identified; these include cell cycle regulation, apoptosis, growth factor pathways, and angiogenesis. Unfortunately, several agents targeting these processes, including erlotinib, gefitinib, and imatinib, have proven ineffective in clinical trials. A greater understanding of the molecular pathways involved in malignant pleural mesothelioma is needed to develop better diagnostics, therapeutics, and preventative measures. Moreover, understanding the biological basis of mesothelioma progression may facilitate personalized treatment approaches, and early identification of poor prognostic indicators may help reduce the heterogeneity of the clinical response. This paper reviews advances in the molecular biology of malignant pleural mesothelioma in terms of pathogenesis, the major molecular pathways and the associated therapeutic strategies, and the roles of biomarkers.

Phase II Study of Asparagine-Glycine-Arginine–Human Tumor Necrosis Factor α, a Selective Vascular Targeting Agent, in Previously Treated Patients With Malignant Pleural Mesothelioma

Purpose

NGR-hTNF consists of human tumor necrosis factor α (hTNF-α) fused to the tumor-homing peptide asparagine-glycine-arginine (NGR) able to selectively bind an aminopeptidase N isoform overexpressed on tumor blood vessels. Hypervascularity is a prominent and poor-prognosis feature of malignant pleural mesothelioma (MPM). Currently, there are no standard options for patients with MPM who are failing a front-line pemetrexed-based regimen. We explored safety and efficacy of NGR-hTNF in this setting.

Patients and Methods

Eligible patients had radiologically documented tumor progression and performance status ≤ 2. Primary study aim was progression-free survival (PFS). NGR-hTNF 0.8 μg/m2 was given intravenously every 3 weeks. A subsequent cohort of patients received 0.8 μg/m2 on a weekly basis.

Results

In the triweekly cohort (n = 43), only one grade 3 drug-related toxicity was noted, and the most common grades 1 to 2 were short-lived chills (71%). The median PFS was 2.8 months (95% CI, 2.3 to 3.3 months). Nineteen patients (44%) had disease control (one had partial response, and 18 had stable diseases) and experienced a median progression-free time of 4.4 months. In the weekly cohort (n = 14), there was no higher toxicity, and median PFS was 3.0 months (95% CI, 1.9 to 4.1 months). Seven patients (50%) had disease control (all stable diseases) and had a median progression-free interval of 9.1 months. In the overall study population (N = 57), median PFS was 2.8 months. Median progression-free time was 4.7 months in twenty-six patients (46%) who achieved disease control. Median survival was 12.1 months.

Conclusion

The tolerability and disease control of NGR-hTNF 0.8 μg/m2 weekly warrant additional evaluation in patients with advanced MPM.

Differential diagnosis and management of focal ground-glass opacities

Focal pulmonary ground-glass opacities (GGOs) can be associated with bronchioloalveolar carcinoma. The present retrospective study aimed to test the validity of a multistep approach to discriminate malignant from benign localised (focal) GGOs, identifies useful diagnostic features on computed tomography (CT), and suggests appropriate management guidelines. A stepwise approach, including oral antibiotics, follow-up high-resolution CT (HRCT) 40-60 days later and CT-guided core biopsy, was used. All cases with localised GGOs detected since 2001 were reviewed. CT features were described according to a structured scheme. In total, 40 patients were evaluated. Of these, 11 patients were diagnosed with benign GGOs, 19 patients had lung cancer and 10 were undetermined. Nonpolygonal shape, apparent radial growth and clear-cut margins were associated with a malignant histology. The specificity of CT findings was low. Diagnostic accuracy increased after oral antibiotics, follow-up HRCT and percutaneous core biopsy. Overall, 18 patients underwent surgery for lung cancer. In conclusion, malignant ground-glass opacities have a fairly typical appearance, but some benign lesions closely mimic their malignant counterparts. The stepwise approach adopted in the present study increased the diagnostic specificity and reduced time to definitive diagnosis. Segmentectomy might be the ideal resection volume for such tumours.

Pemetrexed plus carboplatin in elderly patients with malignant pleural mesothelioma: combined analysis of two phase II trials

The incidence of malignant pleural mesothelioma (MPM) in elderly patients is increasing. In this study, pooled data from two phase II trials of pemetrexed and carboplatin (PC) as first-line therapy were retrospectively analysed for comparisons between age groups. Patients received pemetrexed 500 mg m(-2) and carboplatin AUC 5 mg ml(-1) min(-1) intravenously every 21 days with standard vitamin supplementation. Elderly patients were defined as those >or=70 years old. A total of 178 patients with an ECOG performance status of or=70 years (27%). Grade 3-4 haematological toxicity was slightly worse in >or=70 vs <70-year-old patients, with neutropenia observed in 25.0 vs 13.8% (P=0.11), anaemia in 20.8 vs 6.9% (P=0.01) and thrombocytopenia in 14.6 vs 8.5% (P=0.26). Non-haematological toxicity was mild and similar in the two groups. No significant difference was observed in terms of overall disease control (60.4 vs 66.9%, P=0.47), time to progression (7.2 vs 7.5 months, P=0.42) and survival (10.7 vs 13.9 months, P=0.12). Apart from slightly worse haematological toxicity, there was no significant difference in outcome or toxicity between age groups. The PC regimen is effective and well tolerated in selected elderly patients with MPM.

Role of cMET expression in non-small-cell lung cancer patients treated with EGFR tyrosine kinase inhibitors

BACKGROUND

Approximately 10% of unselected non-small-cell lung cancer (NSCLC) patients responded to the epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment. However, resistance mechanisms are not well understood. We evaluated several potential biological markers of intrinsic EGFR-TKIs-resistance in NSCLC.

MATERIALS AND METHODS

pAKT, pERK, cSRC, E-cadherin, cMET[pY1003], cMET[pY1230/1234/1235], and cMET[pY1349] immunohistochemistry, cMET FISH analysis, and EGFR-, KRAS-, and cMET mutation analysis were carried out on tumor samples from 51 gefitinib-treated NSCLC patients. Biological parameters and survival end points were compared by univariate and multivariate analyses. cMET expression was also investigated in two additional series of patients. The in vitro antiproliferative activity of gefitinib alone or in combination with hepatocyte growth factor and the cMET antibody DN-30 was assessed in NSCLC cells.

RESULTS

EGFR19 deletion and pAKT expression were significantly associated with response (P < 0.0001) and longer time to progression (TTP) (P = 0.007), respectively. Strong cMET[pY1003] membrane immunoreactivity was expressed in 6% of 149 tumors analyzed and was significantly associated with progressive disease (P = 0.019) and shorter TTP (P = 0.041). In vitro, the DN-30 combination synergistically (CI < 1) enhanced gefitinib-induced growth inhibition in all cMET[pY1003]-expressing cell lines studied.

CONCLUSIONS

Activated cMET[pY1003] appears to be a marker of primary gefitinib resistance in NSCLC patients. cMET may be a target in treatment of NSCLC.

Gemcitabine and vinorelbine in pemetrexed-pretreated patients with malignant pleural mesothelioma

BACKGROUND

Pemetrexed-cisplatin chemotherapy is the standard of care in the first-line treatment of unresectable malignant pleural mesothelioma (MPM). Second-line cytotoxic therapy is considered for a growing group of patients, but the optimal treatment has not been defined to date. Gemcitabine and vinorelbine have shown activity in the first-line setting. The objective of this study was to evaluate the activity and toxicity of the gemcitabine-vinorelbine combination in pemetrexed-pretreated patients with MPM.

METHODS

From January 2004 to September 2006, 30 consecutive patients who were pretreated with pemetrexed with or without a platinum-derivative were enrolled. Gemcitabine 1000 mg/m(2) and vinorelbine 25 mg/m(2) were administered intravenously on Days 1 and 8 every 3 weeks. Treatment was repeated for a maximum of 6 cycles or until progression or unacceptable toxicity.

RESULTS

A partial response was observed in 3 patients (10%; 95% confidence interval [CI], 2.1-26.5%), and 10 patients (33.3%; 95% CI, 17.3-52.8%) had stable disease after treatment. Overall, 13 patients (43.3%; 95% CI, 25.5-62.6%) achieved disease control. The median time to progression was 2.8 months (range, 0.6-12.1 months), and the median survival was 10.9 months (range, 0.8-25.3 months). Hematologic toxicity was acceptable, with grade 3 or 4 neutropenia occurring in 11% of patients and thrombocytopenia occurring in 4% of patients; no case of febrile neutropenia was observed. Nonhematologic toxicity generally was mild.

CONCLUSIONS

The gemcitabine and vinorelbine combination was moderately active and had an acceptable toxicity profile in pemetrexed-pretreated patients with MPM. The role of second-line treatment in MPM needs to be evaluated in prospective trials in large series of patients who are stratified according to previous treatment and prognostic factors.

Gene methylation in pleural mesothelioma: correlations with clinico-pathological features and patient's follow-up

Methylation of tumor suppressor genes is among the most frequent alterations in patients with malignant pleural mesothelioma (MPM). The aim of this study was to analyze the promoter methylation status of four tumor suppressor genes, p15(INK4B), p16(INK4A), RASSF1A and NORE1A in MPM. Samples of 79 MPM patients were analyzed using a methylation-specific PCR method. Associations between methylation status, clinico-pathological parameters (including proliferation index) and overall survival (OS) were examined. The analysis documented methylation in 30 cases (38%). The methylation frequency for individual genes was 19% for p15(INK4B) (n=15), 11.4% for p16(INK4A) (n=9), 20.2% for RASSF1A (n=16) and 5.1% for Nore1A (n=4). In the whole series methylation was associated to an increased proliferation index (P=0.05). In patients treated with extrapleural pneumonectomy, methylated MPM showed a trend to a poorer OS in comparison to unmethylated cases (median OS 16 months vs. 35 months, P=0.06, HR=2.01, 95% CI 0.95-4.30). In the overall population, methylation did not correlate to patient outcome but a trend to an improved survival was detectable in ummethylated MPM treated with extrapleural pneumonectomy. This result suggests the need to select homogeneously treated and staged patients with MPM to address whether their methylation profile may impact on patient's survival.

Assessment of tumor response in malignant pleural mesothelioma

Most patients with malignant pleural mesothelioma (MPM) are candidates for chemotherapy during the course of their disease. Assessment of the response with conventional criteria based on computed tomography (CT) measurements is challenging, due to the circumferential and axial pattern of growth of MPM. Such difficulties hinder an accurate evaluation of clinical study results and make the clinical management of patients critical. Several radiological response systems have been proposed, but neither WHO criteria nor the more recent RECIST unidimensional criteria nor hybrid uni- and bidimensional criteria seem to apply to tumor measurement in this disease. Recently, modified RECIST criteria for MPM have been published. Although they are already being used in current clinical trials, they have been criticized based on the high grade of inter-observer variability and on theoretical studies of mesothelioma growth according to non-spherical models. Computer-assisted techniques for CT measurement are being developed. The use of FDG-PET for prediction of response and, more importantly, of survival outcomes of MPM patients is promising and warrants validation in large prospective series. New serum markers such as osteopontin and mesothelin-related proteins are under evaluation and in the future might play a role in assessing the response of MPM to treatment.

Serum level changes of matrix metalloproteinases 2 and 9, vascular endothelial growth factor and epidermal growth factor receptor during platinum-based chemotherapy in advanced non-small cell lung cancer patients

PURPOSE

To evaluate serum changes of matrix metalloproteinases (MMPs) 2 and 9, vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) levels in patients with advanced non-small cell lung cancer (NSCLC) and their association with main clinicopathological parameters during chemotherapy with cisplatin and gemcitabine.

PATIENTS AND METHODS

In this prospective study, consecutive patients with stage III and IV NSCLC were enrolled. Serum MMP2 and 9, VEGF and EGFR levels were monitored in blood samples taken on day 1 of starting chemotherapy (baseline 1st), and after 3 cycles of chemotherapy (2nd) using commercial sandwich ELISA method.

RESULTS

116 patients were evaluated. Males / females 100 / 6, ECOG performance status (PS) 0/1/2: 47/65/4, stage III / IV: 49/67, squamous /adeno/large cell carcinoma 41/31/19. Forty-two (36%) patients achieved partial response (PR), 32 (28%) stable disease (SD) and 42 (36%) showed progressive disease (PD). Mean serum values -/+ standard deviation (SD) of the analyzed markers at baseline/at response evaluation were: EGFR 86 -/+ 87/96 -/+ 47 fmol/ml; MMP9 236 -/+ 156/162 -/+ 133 ng/ml ; MMP2 525 -/+ 189/569 -/+ 201 ng/ml; VEGF 555 -/+ 476/599 -/+ 611 pg/ml; VEGF adjusted for platelets (PLT) 1.9 -/+ 1.45/2.4 -/+ 2.78 pg/10(6). In logistic regression model for response rate adjusted for stage, the increase in MMP9 levels during chemotherapy (mean = 74 ng/ml -/+ SD 140) was predictive for progression (p=0.041) with 5% increase in the odds of progression for an increase of 10 ng.

CONCLUSION

MMP9 level increase was found to be predictive of disease progression. EGFR levels could refl ect extracellular domain (ECD) loss from resistant cells and its shedding into the circulation.

Early Response Evaluation in Malignant Pleural Mesothelioma by Positron Emission Tomography With [18F]Fluorodeoxyglucose

Purpose

Response evaluation with conventional criteria based on computed tomography (CT) is particularly challenging in malignant pleural mesothelioma (MPM) due to its diffuse pattern of growth. There is growing evidence that therapy-induced changes in tumor [18F]fluorodeoxyglucose (FDG) uptake as measured by positron emission tomography (PET) may predict response and patient outcome early in the course of treatment.

Patients and Methods

Patients with histologically proven MPM, not candidates to curative surgery, scheduled to undergo palliative chemotherapy with a pemetrexed-based regimen were eligible for this study. Patients were evaluated by FDG-PET and CT at baseline and after two cycles of therapy. A decrease of 25% or more in tumor FDG uptake as measured by standardized uptake value was defined as a metabolic response (MR). Best overall response from CT scans was determined according to previously published criteria.

Results

Twenty-two patients were included in the study, and 20 were assessable for early metabolic response with FDG-PET. Of these, eight were classified as responders (40%) and 12 as nonresponders (60%). Early MR was significantly correlated to median time-to-tumor progression (TTP) with a median TTP for metabolic responders of 14 months versus 7 months for nonresponders (P = .02). No correlation was found between TTP and radiologic response evaluated by CT. Patients with a MR had a trend toward longer overall survival.

Conclusion

The use of MR evaluated by FDG-PET in the assessment of treatment efficacy in MPM appears promising. Our observations need to be validated in a larger prospective series.

Insulin-like growth factor receptor 1 (IGFR-1) is significantly associated with longer survival in non-small-cell lung cancer patients treated with gefitinib

BACKGROUND

The aim of the study was to assess whether loss of PTEN and expression of insulin-like growth factor receptor 1 (IGFR-1) could be responsible for intrinsic resistance to the tyrosine kinase inhibitor (TKI) gefitinib.

PATIENTS AND METHODS

One hundred and twenty-four gefitinib-treated patients with advanced non-small-cell lung cancer (NSCLC) were analyzed for PTEN and IGFR-1 expression by immunohistochemistry.

RESULTS

IGFR-1 was evaluated in 77 patients and resulted positive in 30 (39.0%). IGFR-1 expression was not significantly associated with clinical or biological characteristics. No difference in response to gefitinib treatment (16.7% versus 12.8%, P = 0.74) and time to progression (2.6 versus 3.06 months, P = 0.83) was observed between IGFR-1+ and IGFR-1-. Median survival was significantly longer in IGFR-1+ patients (17.8 versus 7.3 months, P = 0.013). PTEN expression was successfully evaluated in 93 cases. Loss of PTEN was detected in 19 tumors (20.4%) and was not associated with any clinical or biological characteristic. No difference in terms of response, time to progression and survival was observed between PTEN+ and PTEN- patients. In multivariable analysis IGFR-1 negative status was significantly associated with higher risk of death (hazard ratio 2.21, P = 0.012).

CONCLUSIONS

IGFR-1 expression and loss of PTEN are not associated with intrinsic resistance to gefitinib. Clinical relevance of these two biomarkers as determinant for acquired resistance, and the prognostic role of IGFR-1 expression in patients not exposed to TKIs should be evaluated further.

Phase II study of pemetrexed plus carboplatin in malignant pleural mesothelioma

PURPOSE

This multicenter, phase II clinical study was conducted to evaluate the activity of the combination of pemetrexed and carboplatin in patients with malignant pleural mesothelioma (MPM).

PATIENTS AND METHODS

Chemotherapy-naive patients with measurable disease and adequate organ function, who were not eligible for curative surgery, received pemetrexed 500 mg/m2 and carboplatin area under the plasma concentration-time curve of 5 mg/mL/min, administered intravenously every 21 days. All patients received folic acid and vitamin B12 supplementation. Pemetrexed was provided within the Expanded Access Program.

RESULTS

A total of 102 patients were enrolled. An objective response was achieved in 19 patients (two complete and 17 partial responses), for a response rate of 18.6% (95% CI, 11.6% to 27.5%). Forty-eight patients (47.0%; 95% CI, 37.1% to 57.2%) had stable disease after treatment. Overall, 67 patients (65.7%) achieved disease control (95% CI, 55.6% to 74.8%). Median time to progression was 6.5 months; median overall survival time was 12.7 months. Compliance to treatment was excellent, with a relative dose-intensity of 97% for pemetrexed and 98% for carboplatin. Toxicity was mild, with grade 3 or 4 neutropenia occurring in 9.7% of total cycles and grade 3 or 4 anemia occurring in 3.5% of total cycles. Nonhematologic toxicity was negligible.

CONCLUSION

Treatment with pemetrexed and carboplatin was active and well tolerated in patients with MPM. Disease control rate, time to disease progression, and overall survival were similar to the results achieved with the standard regimen of pemetrexed and cisplatin, suggesting that the carboplatin combination could be an alternative option for these patients.

HER3 genomic gain and sensitivity to gefitinib in advanced non-small-cell lung cancer patients

In non-small-cell lung cancer (NSCLC), sensitivity to tyrosine kinase inhibitors (TKIs) is associated with activating mutations and genomic gain of the epidermal growth factor receptor (EGFR). Preclinical data suggested that HER3 overexpression increases sensitivity to TKIs. A total of 82 NSCLC patients treated with gefitinib (250 mg), and previously evaluated for EGFR and HER2 status by fluorescence in situ hybridisation (FISH) and DNA sequencing, and for Phospho-Akt status by immunohistochemistry, were investigated for HER3 genomic gain by FISH. Patients with high polysomy and gene amplification were considered as HER3 FISH positive (+). HER3 FISH+ pattern was significantly associated with female gender (P=0.02) and never smoking history (P=0.02). Patients with HER3+ tumours (26.8%) had a significantly longer time to progression (3.7 vs 2.7, P=0.04) than patients with HER3− tumours, but not a significantly better response rate or survival. Patients with EGFR+/HER3+ tumours had higher objective response rate (36.4 vs 9.9%, P=0.03) and time to progression (7.7 vs 2.7 months, P=0.03) than patients with EGFR− and/or HER3− tumours, but no significantly longer survival. No difference in response was observed according to HER3 status in patients with EGFR+ tumours. Patients with HER2+/HER3+ tumours had similar outcome as patients with HER2− and/or HER3− tumours. Significantly different clinical end points were not observed between patients with HER3+/P-Akt+ and HER3− and/or P-Akt− tumours. Genomic gain for HER3 is not a marker for response or resistance to TKI therapy in advanced NSCLC patients.

EGFR overexpression in malignant pleural mesothelioma. An immunohistochemical and molecular study with clinico-pathological correlations

The epidermal growth factor receptor (EGFR) is overexpressed in many epithelial malignancies, against which some antitumoral drugs have been developed. There is a lack of information as to EGFR expression in malignant pleural mesothelioma (MPM), an aggressive and fatal cancer poorly responsive to current oncological treatments. Our aim was to: (a) compare EGFR immunohistochemical expression with mRNA levels measured by real time PCR; (b) assess the relationships between EGFR expression and clinico-pathological data including survival; (c) analyze the EGFR mutations. We developed an immunohistochemical method of EGFR evaluation based on the number of immunoreactive cells and staining intensity in 61 MPMs. EGFR immunoreactivity was documented in 34/61 (55.7%) cases. A significant correlation between EGFR protein and mRNA levels (p = 0.0077) was found, demonstrating the reliability of our quantification method of EGFR membrane expression. Radically resected patients (p = 0.005) and those with epithelial histotype (p = 0.048) showed an increased survival. No statistical correlation between EGFR immunoreactivity and patients survival was observed. No EGFR mutation was documented. This study documents EGFR overexpression in MPM at the protein and the transcriptional levels; it proposes a reliable method for EGFR expression evaluation in MPM. EGFR levels are not associated with clinico-pathological features of patients, including survival.

Increased HER2 gene copy number is associated with response to gefitinib therapy in epidermal growth factor receptor-positive non-small-cell lung cancer patients

PURPOSE

In non-small-cell lung cancer (NSCLC), response to tyrosine kinase inhibitors (TKIs) is significantly associated with the presence of increased copy number and/or activating mutations of the epidermal growth factor receptor gene (EGFR). Preclinical data indicate that HER2, a member of the EGFR family, could enhance TKI sensitivity.

PATIENTS AND METHODS

HER2 gene copy numbers per cell were evaluated by fluorescent in situ hybridization (FISH) in 102 NSCLC patients treated with gefitinib, and previously evaluated for EGFR status by FISH, immunohistochemistry, and presence of mutations.

RESULTS

Patients with HER2 high copy number (high polysomy and gene amplification [HER2 FISH positive]) represented 22.8% of patients, and compared with patients with no or low gain (HER2 FISH negative), had significantly better objective response (OR, 34.8% v 6.4%; P = .001), disease control rate (DCR, 56.5% v 33.3%; P = .04), time to progression (TTP, 9.05 v 2.7 months; P = .02), and a trend toward longer overall survival (OS, 20.8 v 8.4 months; P = .056). HER2 protein expression investigated by immunohistochemistry was positive in only five of 72 (7%) patients analyzed and all 89 patients tested by DNA sequencing were negative for mutations in HER2 exon 20. Patients with HER2 FISH-positive tumors displaying increased expression of EGFR protein, gene gain, or mutations (EGFR positive) had a significantly better OR, DCR, TTP, and OS than patients negative for both receptors.

CONCLUSION

Increased copy number of the HER2 gene is associated with gefitinib sensitivity in EGFR-positive patients, supporting use of HER2 FISH analysis for selection of patients for TKI therapy.

Automatic registration of PET and CT studies for clinical use in thoracic and abdominal conformal radiotherapy

AIM

Implementation and validation of an automatic registration method based on mutual information (MI) for the integration of thoracic and abdominal positron emission tomography (PET)/computed tomography (CT) studies, with the purpose to facilitate in a clinical context the inclusion of PET metabolic information in conformal radiotherapy (RT).

METHODS

Registration was obtained by modeling a rigid spatial transformation between CT and PET transmission studies. The registration method was based on Normalized Mutual Information (NMI), by iteratively transforming the PET volume, until its optimal alignment to the CT study is achieved, in correspondence of the maximum of NMI. To avoid entrapment in local maxima and to improve convergence speed we introduced a multiresolution scheme. Accuracy of the proposed approach was investigated in experimental data, relative to phantom and patient studies, acquired in conditions similar to clinical situations.

RESULTS

In phantom studies the mean error in the 3D space is 3.6 mm (range 3-4 mm) in thoracic region and 3.2 mm (range 2.9-3.7 mm) in abdominal region, considerably less than PET spatial resolution. In patient studies the spatial mean error increases with respect to phantom studies (5.4 mm and 5.2 mm for thorax and abdomen, respectively) but remains comparable to the PET spatial resolution. The accuracy of spatial realignment was thus found adequate for the registration of PET/CT registration, if good patient repositioning was adopted.

CONCLUSIONS

The proposed registration method, based on MI, was validated for the integration of PET/CT studies of patients candidate for thoracic and abdominal conformal RT. The method is automatic and provided with a user interface, thus suitable for clinical use.

Feasibility of [18F]FDG-PET and coregistered CT on clinical target volume definition of advanced non-small cell lung cancer

AIM

To prospectively evaluate the impact of coregistered positron emission tomography (PET) and computed tomography (CT) in 3D conformal radiotherapy (3D-CRT) planning in patients with non-small lung cancer (NSCLC).

METHODS

Twenty-one patients (median age: 57 years; range: 42-80 years) referred to 3D-CRT for NSCLC were recruited. Positron emission tomography with 18F-fluorodeoxyglucose ([18F]FDG-PET) and conventional CT images were coregistered (PET/CT images) using a commercial software package based on surface matching technique. Neoplastic areas were contoured on [18F]FDG-PET images with the aid of the correspondent CT image by a nuclear medicine physician. CT images and their relative PET contours were then transferred to treatment planning system. A radiation oncologist firstly contoured clinical target volumes (CTV) on CT scan alone (CTV-CT), and then on coregistered PET/CT images (CTV-PET/CT). CTV-CT and CTV-PET/CT were compared for each patient; a difference higher than 25% was considered of clinical relevance.

RESULTS

Three patients were shifted to palliative radiotherapy for metastatic disease or very large tumor size, showed by [18F]FDG-PET. Of the remaining 18 patients a CTV change, after inclusion of PET/CT data, was observed in 10/18 cases (55%): larger in 7/18 (range 33-279%) and smaller in 3/18 patients (range 26-34%), mainly due to inclusion or exclusion of lymph-nodal disease and to better definition of tumor extent. CTV changes smaller than 25% occurred in the remaining 8/18 patients.

CONCLUSIONS

[18F]FDG-PET and CT images co-registration in radiotherapy treatment planning led to a change in CTV definition in the majority of our patients, which may significantly modify management and radiation treatment modality in these patients.

Epidermal growth factor receptor gene and protein and gefitinib sensitivity in non-small-cell lung cancer

BACKGROUND

Gefitinib is a selective inhibitor of the epidermal growth factor (EGFR) tyrosine kinase, which is overexpressed in many cancers, including non-small-cell lung cancer (NSCLC). We carried out a clinical study to compare the relationship between EGFR gene copy number, EGFR protein expression, EGFR mutations, and Akt activation status as predictive markers for gefitinib therapy in advanced NSCLC.

METHODS

Tumors from 102 NSCLC patients treated daily with 250 mg of gefitinib were evaluated for EGFR status by fluorescence in situ hybridization (FISH), DNA sequencing, and immunohistochemistry and for Akt activation status (phospho-Akt [P-Akt]) by immunohistochemistry. Time to progression, overall survival, and 95% confidence intervals (CIs) were calculated and evaluated by the Kaplan-Meier method; groups were compared using the log-rank test. Risk factors associated with survival were evaluated using Cox proportional hazards regression modeling and multivariable analysis. All statistical tests were two-sided.

RESULTS

Amplification or high polysomy of the EGFR gene (seen in 33 of 102 patients) and high protein expression (seen in 58 of 98 patients) were statistically significantly associated with better response (36% versus 3%, mean difference = 34%, 95% CI = 16.6 to 50.3; P<.001), disease control rate (67% versus 26%, mean difference = 40.6%, 95% CI = 21.5 to 59.7; P<.001), time to progression (9.0 versus 2.5 months, mean difference = 6.5 months, 95% CI = 2.8 to 10.3; P<.001), and survival (18.7 versus 7.0 months, mean difference = 11.7 months, 95% CI = 2.1 to 21.4; P = .03). EGFR mutations (seen in 15 of 89 patients) were also statistically significantly related to response and time to progression, but the association with survival was not statistically significant, and 40% of the patients with mutation had progressive disease. In multivariable analysis, only high EGFR gene copy number remained statistically significantly associated with better survival (hazard ratio = 0.44, 95% CI = 0.23 to 0.82). Independent of EGFR assessment method, EGFR+/P-Akt+ patients had a statistically significantly better outcome than EGFR-, P-Akt-, or EGFR+/P-Akt- patients.

CONCLUSIONS

High EGFR gene copy number identified by FISH may be an effective molecular predictor for gefitinib efficacy in advanced NSCLC.