Iron in blood cells: Function, relation to disease, and potential for magnetic separation

Iron in blood cells has several physiological functions like transporting oxygen to cells and maintaining iron homeostasis. Iron is primarily contained in red blood cells (RBCs), but monocytes also store iron as these cells are responsible for the recycling of senescent RBCs. Iron also serves an important role related to the function of different leukocytes. In inflammation, iron homeostasis is dependent on cytokines derived from T cells and macrophages. Fluctuations of iron content in the body lead to different diseases. Iron deficiency, which is also known as anemia, hampers different physiological processes in the human body. On the other hand, genetic or acquired hemochromatosis ultimately results in iron overload and leads to the failure of different vital organs. Different diagnoses and treatments are developed for these kinds of disorders, but the majority are costly and suffer from side effects. To address this issue, magnetophoresis could be an attractive technology for the diagnosis (and in some cases treatment) of these pathologies due to the paramagnetic character of the cells containing iron. In this review, we discuss the main functions of iron in blood cells and iron-related diseases in humans and highlight the potential of magnetophoresis for diagnosing and treating some of these disorders.

Abstract P5-18-14: The relative risk of pneumonitis associated with neoadjuvant chemoimmunotherapy use in early-stage triple-negative breast cancer: A systematic review and meta-analysis

Background: Pneumonitis is significant toxicity of immune checkpoint inhibitors (ICIs). Lately, multiple clinical trials have demonstrated that neoadjuvant chemoimmunotherapy improves pathological complete response rate in high-risk early-stage triple-negative breast cancer (TNBC), an exciting development in breast oncology. In this systematic review and meta-analysis, we attempt to determine the risk of pneumonitis associated with the use of chemoimmunotherapy in early-stage TNBC. Methods: We conducted a systematic search in the PUBMED, MEDLINE, EMBASE, American Society of Clinical Oncology, and San Antonio Breast Cancer Symposium meeting abstracts as per PRISMA guidelines from inception through May 30, 2021. Published phase 2 and 3 randomized control trials (RCTs) using neoadjuvant ICI plus chemotherapy (ICI+C) in the study arm for early-stage TNBC and reporting the number of events for pneumonitis were included in the analyses. We used the Mantel-Haenszel method and random-effects model to calculate the estimated pooled risk ratio (RR) with a 95% confidence interval (CI). Heterogeneity was tested with the I2 value and Cochran’s Q-test. Results: Two phase 3 RCTs (IMpassion031 and KEYNOTE-522) and Two phase 2 RCTs (GeparNuevo and I-SPY2) were included in the final analysis. These RCTs randomized 1,106 patients in the ICI+C arm and 819 patients in the placebo + chemotherapy (P+C) arm. We have included some essential characteristics of these studies, such as the number of patients and chemotherapy regimen used in table 1. Any grade pneumonitis was reported in 1.90% of patients in the ICI+C arm versus 1.47% of patients in the P+C arm. The relative risk of any grade pneumonitis was not significantly different between the arms (the pooled RR = 1.29, 95% CI: 0.64-2.63, P = 0.48, I2 = 0%). Grade 3/4 pneumonitis was reported in 0.54% of patients in the ICI+C arm and 0.37% of patients in the P+C arm. The relative risk of grade 3/4 pneumonitis was also not significantly different between the arms (the pooled RR = 1.36, 95% CI: 0.36-5.13, P = 0.65, I2 = 0%). One grade 5 pneumonitis was reported in the KEYNOTE-522 trial in the ICI+C arm. Conclusions: Neoadjuvant chemoimmunotherapy does not significantly increase any grade and grade 3/4 pneumonitis risk in early-stage triple-negative breast cancer patients compared to chemotherapy. This finding is reassuring and clinically relevant. However, clinical vigilance is necessary.

Table 1.Characteristics of the studies included in the meta-analysisStudyPhaseICI usedC usedNo. of patients (ICI+C)No. of patients (P+C)GaperNuevo2DurvalumabNab-paclitaxel + EC9282I-SPY22PembrolizumabPaclitaxel + AC69181IMpassion0313AtezolizumabNab-paclitaxel + AC164167KEYNOTE-5223PembrolizumabPaclitaxel + carboplatin + AC/EC781389AC: doxorubicin + cyclophosphamide; C: chemotherapy; EC: epirubicin + cyclophosphamide; ICI: immune checkpoint inhibitor; P: placebo

Citation Format: Nusrat Jahan, Shabnam Rehman, Srikala Meda, Lukman Tijani. The relative risk of pneumonitis associated with neoadjuvant chemoimmunotherapy use in early-stage triple-negative breast cancer: A systematic review and meta-analysis [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-18-14.

Abstract P5-18-08: The relative risk of various endocrinopathies associated with neoadjuvant chemoimmunotherapy use in early-stage triple-negative breast cancer: A systematic review and meta-analysis

Background: Immune checkpoint inhibitors (ICIs) are known to cause various irreversible endocrinopathies. Lately, multiple clinical trials have demonstrated that the addition of ICI to the standard neoadjuvant chemotherapy improves pathological complete response (pCR) rate in high-risk early-stage triple-negative breast cancer (TNBC). The pCR has long been regarded as a surrogate marker of favorable outcomes in early-stage TNBC. This systematic review and meta-analysis attempt to determine the risks of various endocrinopathies associated with neoadjuvant chemoimmunotherapy use in early-stage TNBC. Methods: We conducted a systematic search in the PUBMED, MEDLINE, EMBASE, American Society of Clinical Oncology, and San Antonio Breast Cancer Symposium meeting abstracts as per PRISMA guidelines from inception through May 30th, 2021. Published phase 2 and 3 randomized control trials (RCTs) using neoadjuvant ICI plus chemotherapy (ICI+C) in the intervention arm for early-stage TNBC and reporting the number of events for various endocrinopathies were included in the analyses. We used the Mantel-Haenszel method and random-effects model to calculate the estimated pooled risk ratio (RR) with a 95% confidence interval (CI). Heterogeneity was tested with the I2 value and Cochran’s Q-test. Results: Two phase 3 RCTs (IMpassion031 and KEYNOTE-522) and Two phase 2 RCTs (GeparNuevo and I-SPY2) were included in the final analysis. These RCTs randomized 1,106 patients in the ICI+C arm and 819 patients in the placebo plus chemotherapy (P+C) arm. Some essential characteristics of these trials are included in table 1. The incidence of any grade hypothyroidism was 12.84% in the ICI+C arm versus 3.17% in the P+C arm. The pooled RR of any grade hypothyroidism was 3.63 (95% CI: 1.78-7.43, p = 0.0004, I2 = 28%), which was statistically significant. The incidence of any grade hyperthyroidism was 5.24% in the ICI+C arm versus 0.98% in the P+C arm. The pooled RR of any grade hyperthyroidism was 4.08 (95% CI: 1.94-8.59, p = 0.0002, I2 = 3%), which was statistically significant. The incidence of any grade adrenal insufficiency was 2.66% in the ICI+C arm versus 0.14% in the P+C arm. The pooled RR of any grade adrenal insufficiency was 6.84 (95% CI: 0.43-108.95, p = 0.17, I2 = 62%), which was not significant. The incidence of any grade hypophysitis was 1.45% in the ICI+C arm versus 0.16% in the P+C arm. The pooled RR of any grade hypophysitis was 5.29 (95% CI: 0.96-29.25, p = 0.06, I2 = 0%), which was not significant. The incidence of any grade diabetes mellitus was 0.42% in the ICI+C arm versus 0.18% in the P+C arm. The pooled RR of any grade diabetes mellitus 1.81 (95% CI: 0.24-13.63, p = 0.57, I2 = 0%), which was not statistically significant. Conclusions: The addition of immune checkpoint inhibitors (ICIs) to the standard neoadjuvant chemotherapy significantly increases the risk of any grade hypothyroidism and hyperthyroidism. Although the incidences of adrenal insufficiency, hypophysitis, and diabetes mellitus were numerically higher in the ICI+C arm than the P+C arm, they have not achieved statistical significance, possibly due to the rarity of these events. Careful endocrine functions monitoring and appropriate early interventions are crucial in reducing endocrine-related morbidities and mortalities in these patients.

Table 1.Characteristics of the studies included in the meta-analysisStudyPhaseICI usedC usedNo. of patients (ICI+C)No. of patients (P+C)GaperNuevo2DurvalumabNab-paclitaxel + EC9282I-SPY22PembrolizumabPaclitaxel + AC69181IMpassion0313AtezolizumabNab-paclitaxel + AC164167KEYNOTE-5223PembrolizumabPaclitaxel + carboplatin + AC/EC781389AC: doxorubicin + cyclophosphamide; C: chemotherapy; EC: epirubicin + cyclophosphamide; ICI: immune checkpoint inhibitor; P: placebo

Citation Format: Nusrat Jahan, Shabnam Rehman, Lukman Tijani. The relative risk of various endocrinopathies associated with neoadjuvant chemoimmunotherapy use in early-stage triple-negative breast cancer: A systematic review and meta-analysis [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-18-08.

Plexus Slim®-Induced Immune Thrombocytopenic Purpura

Primary immune thrombocytopenic purpura (ITP) is a common cause of thrombocytopenia. Due to the many possible precipitating factors, the diagnostic approach can be complex in nature. Much of the published literature on drug-induced ITP (DITP) report on quinine-induced thrombocytopenia. Here we present a case of the proposed dietary cause of DITP by the weight loss supplement Plexus® which contains two potential thrombocytopenia-causing compounds, garcinia cambogia fruit extract, and chromium polynicotinate. This case highlights how a thorough patient history, including evaluation of supplement use and dietary habits, can be of the utmost importance in the workup of ITP.

Abstract P5-14-10: Relative risk of grade 3 and higher hematological toxicities with trastuzumab emtansine: A systematic review and meta-analysis of published phase 3 randomized controlled trials

Background: Trastuzumab Emtansine (T-DM1) is a HER2 targeted antibody-drug conjugate consisting of anti-HER2 IgG1 antibody trastuzumab and maytansine derivative DM-1. Trastuzumab inhibits HER2 receptor signaling and mediates antibody-dependent cell-mediated cytotoxicity; and DM-1 is a microtubule inhibitor causing cell cycle arrest and apoptosis. In addition, the former ensures selective intracellular delivery of the latter into the HER2 overexpressing cells. Currently, T-DM1 is approved for HER2-positive breast cancer both in the metastatic and in the adjuvant settings. We conducted a systematic review and meta-analysis of phase 3 randomized controlled trials (RCTs) using T-DM1 to determine the relative risk of grade 3 and higher hematological toxicities associated with T-DM1.

Methods: We conducted a systematic search at PUBMED, MEDLINE, EMBASE and meeting abstracts as per PRISMA guidelines from inception until March 31st, 2019. Published phase 3 RCTs comparing T-DM1 with other therapies in patients with HER2-positive cancers and reporting the number of events of grade 3 and higher hematological toxicities in both intervention and control arms were included in the final analysis. The primary meta-analytic approach was a random effects model using the Mantel-Haenszel (MH) method, and it was used to calculate the estimated pooled risk ratio (RR) with 95% confidence interval (CI). Heterogeneity was tested with I2 value and Cochran’s Q-test.

Results: Six RCTs (EMILIA, GATSBY, KRISTINE, KATHERINE, MARIANNE, and TH3RESA) randomizing 4882 participants (2807 in the T-DM1 arms and 2075 in the control arms) were included in the final analysis for grade 3 and higher anemia and thrombocytopenia. KATHERINE trial did not report the number of grade 3 and higher neutropenia. Five RCTs (EMILIA, GATSBY, KRISTINE, MARIANNE and TH3RESA) including 3422 (2067 in the T-DM1 arms and 1355 in the control arms) were included in the final analysis for grade 3 and higher neutropenia. Five studies (EMILIA, KATHERINE, KRISTINE, MARIANNE, and TH3RESA) were conducted in breast cancer patients, and one (GATSBY) was done in gastric/gastro-esophageal junction adenocarcinoma patients. GATSBY was a phase 2/3 study and rest were phase 3 RCTs. Patients in the control arms received variable systemic therapies across trials: taxane based regimens were used in GATSBY, KRISTINE, and MARIANNE trials; capecitabine and lapatinib combination was used in EMILIA trial; treatments of physician’s choice were used in TH3RESA trial; and trastuzumab alone was used in KATHERINE trial. The pooled RR of grade 3 and higher thrombocytopenia was significantly higher in the T-DM1 group compared to the control group (pooled RR: 8.59, 95% CI: 1.54-48.00, P= 0.01, I2= 82%). The pooled RR of grade 3 and higher anemia was not significantly different in the T-DM1 group compared to the control group (pooled RR: 1.23, 95% CI: 0.63-2.41, P= 0.54, I2= 72%). The pooled RR of grade 3 and higher neutropenia was significantly lower in the T-DM1 group compared to the control group (pooled RR: 0.16, 95% CI: 0.09 -0.32, P< 0.00001, I2= 76%).

Conclusion: T-DM1 was associated with increased risk of grade 3 and higher thrombocytopenia, but reduced risk of grade 3 and higher neutropenia compared to control regimens. The exact mechanism of these findings is not clear, yet they may have some implications in adopting appropriate therapeutic strategies for the patients. The patients who are on T-DM1, a careful monitoring of the platelet will be helpful for the early identification of thrombocytopenia and initiation of appropriate interventions. On the other hand, T-DM1 may be a relatively safer option for the patients who are at risk of developing neutropenia and infectious complications.

Citation Format: Nusrat Jahan, Rafiullah Khan, Shabnam Rehman, Fred Hardwicke, Francis Mogollon-Duffo, Lukman Tijani. Relative risk of grade 3 and higher hematological toxicities with trastuzumab emtansine: A systematic review and meta-analysis of published phase 3 randomized controlled trials [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-14-10.

CLO19-052: Incidence of Ribociclib-Associated Cardiac Conduction Abnormalities in Patients With Hormone Receptor-Positive HER2-Negative Metastatic Breast Cancer: A Combined Analysis of 3 Phase III Randomized Controlled Trials

Introduction: Ribociclib, a cyclin-dependent kinase 4/6 inhibitor, has improved survival in patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER 2)-negative advanced breast cancer. Despite remarkable efficacy, potential cardiac toxicities remain a concern. We undertook a combined analysis of randomized controlled trials (RCT) to estimate the incidence of prolongation of corrected QT interval (QTcF) associated with ribociclib. Methods: We performed systematic search of Embase, MEDLINE, and meeting abstracts till September 30, 2018, to find all phase 3 RCTs comparing ribociclib with other agents or placebo in patients with advanced breast cancer and reporting QTc prolongation as adverse event. Mantel-Haenszel method was used to calculate the pooled risk ratio (RR) and absolute risk difference (RD) with 95% CI. Fixed effects model was applied. Heterogeneity was assessed using I2 statistic. Results: Three phase III studies with 2,062 participants were included. Randomization ratio was 1 to 1 in MONALEESA-2 and 7 studies and 2 to 1 in MONALEESA-3 study. I2 statistic was 0, suggesting homogeneity across studies. Prolongation of QTcF >60 msec from baseline was observed in 72 patients (61 had post-baseline QTcF >480 msec) in ribociclib arm, compared to 7 in control arm. Pooled RR for prolongation of QTcF was 7.956 (95%CI: 3.683–17.187; P<.001) and RD was 0.055 (95%CI: 0.040–0.070; P<.001). The risk of having a post-baseline QTcF >480 msec was significantly higher with ribociclib vs control (pooled RR, 4.002; 95%CI: 2.161–7.412; P<.001; and RD, 0.039; 95%CI: 0.024–0.055; P<.001). A total of 16 (1.38%) patients in the ribociclib arm had dose reduction, interruption, or discontinuation due to QTcF prolongation, as opposed to 3 (0.33%) in control arm. Pooled RR and RD were statistically significant at 4.204 (95%CI: 1.333–3.260; P=.014) and 0.012 (95%CI: 0.004–0.021; P=.006), respectively. Conclusion: Advanced breast cancer patients may have cardiac dysfunction due to prior cardiotoxic chemotherapies. In our meta-analysis, ribociclib was associated with significantly higher risk of QTc prolongation and the resultant dosing inconsistencies and discontinuation. Early detection of this potential adverse event and timely intervention are critical.

CLO19-053: Incidence of Cabozantinib-Associated Palmar-Plantar Erythrodysesthesia and Hypertension in Patients With Metastatic Solid Tumors: A Combined Analysis of 4 Phase III Randomized Controlled Trials

Background: Tyrosine kinases such as VEGFR, KIT, RET, MET are implicated in development and progression of several solid tumors. Cabozantinib is an oral multiple tyrosine kinase inhibitor and has shown survival benefits in several solid tumors. Yet, there are notable toxicities. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of palmar-plantar erythrodysesthesia (PPE) and hypertension in patients with metastatic solid tumors treated with cabozantinib. Methods: We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases, and meeting abstracts through September 2018. Phase III RCTs that mention PPE and hypertension as adverse effects were incorporated in the analysis. Mantel-Haenszel method was used to calculate the estimated pooled risk ratio (RR), and risk difference (RD) with 95% CI. Random effects model was applied. Heterogeneity was assessed using I2 statistic. Results: 4 phase III RCTs with total of 2,703 patients, comparing cabozantinib (C) vs everolimus, C vs placebo, C vs prednisone, were included. I2 statistic was 70.70, suggesting some heterogeneity among RCTs. All grade-PPE incidence was 666 (39.3%) in cabozantinib arm vs 38 (3.76%) in control arm with a RR of 11.378 (95% CI: 6.545–19.782; P<.0001). The absolute RD was 0.383 (95% CI: 0.294–0.473; P<.0001). High-grade PPE was reported in 172 (10.15%) in cabozantinib group vs 3 (0.29%) in control group with a RR of 19.077 (95% CI: 5.733–63.476; P<.0001). The RD was 0.105 (95% CI: 0.049–0.160; P<.0001). The overall incidence of hypertension was noted at 524 (30.95%) in cabozantinib arm vs 84 (8.31%) in control arm. The pooled RR of hypertension was 4.131 (95% CI: 2.656–6.425; P<.0001) and RD was 0.240 (95% CI: 0.186–0.295; P<.0001). High-grade hypertension was reported in 276 (16.30%) in cabozantinib group vs 41 (4.05%) in control group with a RR of 4.324 (95% CI: 2.484–7.525; P<.0001) and RD was 0.115 (95% CI: 0.085–0.144; P<.0001). Conclusion: Our meta-analysis demonstrated that cabozantinib contributed to significant toxicity of any-grade and high-grade PPE as well as hypertension, with a RR of 19.07 for grade 3 and 4 PPE. Recognizing these toxicities and prompt intervention with proper supportive care may enhance patients’ quality of life, ultimately leading to better compliance.

Abstract P4-16-06: Incidence of interstitial lung disease in patients with HER2-positive advanced breast cancer treated with everolimus and trastuzumab: A combined analysis of two phase 3 randomized controlled trials

Background: The human epidermal growth factor receptor 2 (HER2) protein is overexpressed in approximately one fourth of breast tumors. Trastuzumab resistance has been demonstrated via aberrant PI3K/AKT/mTOR signaling due to PTEN loss. To circumvent this resistance mechanism, everolimus, an oral mTOR inhibitor, has been employed in treatment of HER2-positive advanced breast cancer (ABC). Lung toxicity due to everolimus is well established and has been reported with trastuzumab. Yet, the incidence of interstitial lung disease (ILD), when everolimus was added to trastuzumab, has never been reported. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine the incidence of ILD in patients with HER2-positive ABC treated with both everolimus and trastuzumab.

Methods: We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through January 2018. Phase 3 RCTs that mention ILD as an adverse effect were incorporated in the analysis. The primary meta- analytic approach was a fixed effects model using the Mantel-Haenszel (MH) method. It was used to calculate the estimated pooled risk ratio (RR), and risk difference (RD) with 95% confidence interval (CI).

Results: A total of 1272 patients with HER-2 positive ABC from two phase 3 RCTs were eligible. Studies compared everolimus + paclitaxel + trastuzumab vs paclitaxel + trastuzumab and everolimus + vinorelbine + trastuzumab vs vinorelbine + trastuzumab. The initial dose of everolimus in BOLERO-1 was 10mg per day and in BOLERO-3, 5mg per day was used. The median relative dose intensity of everolimus was reduced to 0.54 in BOLERO-1 due to toxicity related dose reductions and dose interruptions. The randomization ratio of everolimus to placebo was 2 to 1 in BOLERO-1 and 1 to 1 in BOLERO-3. Everolimus was utilized in trastuzumab-resistant ABC after prior taxane therapy in the BOLERO-3 study (n= 562) and as first-line treatment in the BOLERO-1 study (n= 710). The I2 statistic for heterogeneity was 0, and the heterogeneity X2 (Cochran's Q) was 1 (P= 0), suggesting homogeneity among RCT. The incidence of all-grade ILD was 31 (4.122%) in the everolimus group vs 3 (0.577%) in control group and of high-grade ILD was 11 (1.463%) in everolimus arm vs 0 (0%) in the control arm. The pooled RR for all-grade ILD was significant at 7.258 (95% CI: 2.130 – 24.733, p = 0.002) and the absolute RD was 0.035 (95% CI: 0.019 – 0.050, P &lt; 0.001). The pooled RR for high-grade ILD was noted at 7.930 (95% CI: 0.997 – 63.044, p = 0.050) and the absolute RD was 0.014 (95% CI: 0.004 – 0.024, P = 0.004).

Conclusions: Approximately 0.46 and 0.61% of patients on trastuzumab alone have been reported to develop ILD in previous studies. Our study showed that the addition of reduced dose of everolimus to trastuzumab, significantly contributed a higher incidence in all grades of ILD with a relative risk of 7.93 for grade 3 and 4 ILD. More randomized trials are required to determine the definitive incidence and actual relation of ILD as well as the optimal dose of everolimus, when combined with trastuzumab or other chemotherapy.

Citation Format: Thein KZ, Swarup S, Sultan A, Tijani L, D'Cunha N, Hardwicke FT, Awasthi S, Jones C. Incidence of interstitial lung disease in patients with HER2-positive advanced breast cancer treated with everolimus and trastuzumab: A combined analysis of two phase 3 randomized controlled trials [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-16-06.

Discontinuation of adjuvant sunitinib due to adverse events in patients with high-risk renal cell carcinoma after nephrectomy: A combined analysis of phase III trials

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Background: Dysregulation in the vascular endothelial growth factor (VEGF) pathway has been implicated in the pathogenesis of renal cell carcinoma (RCC). Sunitinib is an oral VEGF receptor tyrosine kinase inhibitor and has been approved in the adjuvant treatment of high-risk RCC. However, there are significant adverse events, impacting patients’ quality of life, and leading to treatment discontinuation. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of high-grade toxicities and the rate of treatment discontinuation due to adverse events. Methods: We conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts from inception through June 2018. Phase III RCTs which utilized adjuvant sunitinib in high risk RCC after nephrectomy and mentioned treatment interruption or discontinuation or dose reduction due to adverse events were included. Mantel-Haenszel (MH) method was used to calculate the estimated pooled risk ratio (RR) with 95% confidence interval (CI). Fixed effects model was applied. Results: Two phase III RCTs with a total of 1866 patients were eligible. Studies utilized sunitinib versus placebo. The randomization ratio was 1:1 in both ASSURE and S-TRAC studies. The incidence of high-grade adverse events was 568 (60.5%) in sunitinib group versus 183 (19.6%) in placebo arm, with the relative risk of 3.10 (95% CI: 2.69 – 15.93, P < 0.001). The reduction in dose was reported in 541 (57.9%) in study arm versus 86 (9.2%) in placebo group. The pooled RR for dose reduction was statistically significant at 6.28 (95% CI: 5.10 – 7.74, P < 0.001). The treatment discontinuation rate was 27.9% higher with sunitinib than with placebo (RR - 4.14; 95% CI: 3.31 – 5.16, P < 0.001). Conclusions: Our meta-analysis demonstrated that the rate of dose reduction, treatment discontinuation and the risk of grade 3 and 4 adverse events were notably high in sunitinib group. Timely recognition and proper supportive care are entailed in minimizing those adverse events which may ultimately improve patients’ quality of life and overall compliance.

Anticancer activity of 2'-hydroxyflavanone towards lung cancer

In previous studies, we found that 2'-hydroxyflavonone (2HF), a citrus flavonoid, inhibits the growth of renal cell carcinoma in a VHL-dependent manner. This was associated with the inhibition of glutathione S-transferases (GSTs), the first step enzyme of the mercapturic acid pathway that catalyzes formation of glutathione-electrophile conjugates (GS-E). We studied 2HF in small cell (SCLC) and non-small cell (NSCLC) lung cancer cell lines for sensitivity to 2HF antineoplastic activity and to determine the role of the GS-E transporter Rlip (Ral-interacting protein; RLIP76; RALBP1) in the mechanism of action of 2HF. Our results show that 2HF induced apoptosis in both histological types of lung cancer and inhibited proliferation and growth through suppression of CDK4, CCNB1, PIK3CA, AKT and RPS6KB1 (P70S6K) signaling. Increased E-cadherin and reduced fibronectin and vimentin indicated inhibition of epithelial-mesenchymal transition. Additionally, 2HF inhibited efflux of doxorubicin and increased its accumulation in the cells, but did not add to the transport inhibitory effect of anti-Rlip antibodies alone. Binding of Rlip to 2HF was evident from successful purification of Rlip by 2HF affinity chromatography. Consistent with increased drug accumulation, combined treatment with 1-chloro-2, 4-dinitrobenzene, reduced the GI50 of 2HF by an order of magnitude. Results of in-vivo nude mouse xenograft studies of SCLC and NSCLC, which showed that orally administered 2HF inhibited growth of both histological types of lung cancer, confirmed in-vitro study results. Our result suggest that Rlip inhibition is likely a mechanism of action. Our findings are basis of proposing 2HF as therapeutic or preventative drug for lung cancer.

A systematic review and meta-analysis of randomized controlled trials to evaluate the risk of fatigue and pain among patients treated with ibrutinib

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Background: Bruton’s tyrosine kinase (BTK), a kinase downstream of the B-cell receptor, involves in the B cell survival and proliferation and has become an attractive therapeutic target. Ibrutinib is an oral potent, covalent inhibitor of BTK and hence employed in many hematologic malignancies. We performed a systematic review and pooled analysis of randomized controlled trials (RCTs) to determine the risk of fatigue and pain among patients treated with ibrutinib. Methods: We performed a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through December 31, 2016. RCTs that mention fatigue, arthralgia, muscle spasm, back pain, pain in extremity and myalgia as adverse effects were incorporated in the analysis. Mantel-Haenszel method was used to calculate the estimated pooled risk ratio with 95% confidence interval (CI). Results: Four phase 3 RCTs with a total of 1505 patients were eligible for the analysis. Studies compared Ibrutinib (I) vs ofatumumab, I vs chlorambucil, I+ bendamustine (B)+ rituximab (R) vs placebo + B+ R and I vs temsirolimus were included in the analysis. The relative risks (RR) of all-grade side effects were as follows: fatigue, 0.87 (95% CI: 0.74- 1.03, p = 0.11); arthralgia, 1.97 (95% CI: 1.11- 3.50, p = 0.02); muscle spasm, 1.92 (95% CI: 1.22- 3.02, p = 0.005); back pain, 1.56 (95% CI: 1.02- 2.37, p = 0.03); pain in extremity, 2.47 (95% CI: 1.14- 5.36, p = 0.02); and myalgia, 2.68 (95% CI: 1.18- 6.05, p = 0.01). The RR of high-grade side effects were as follows: fatigue, 0.70 (95% CI: 0.37- 1.33, p = 0.28); arthralgia, 3.62 (95% CI: 0.74- 17.66, p = 0.11); back pain, 2.80 (95% CI: 0.42- 18.35, p = 0.28); pain in extremity, 2.96 (95% CI: 0.31- 28.4, p = 0.34); and myalgia, 2.96 (95% CI: 0.31- 28.44, p = 0.34). Conclusions: Our meta-analysis demonstrated that the risk of all-grade arthralgia, muscle spasm, back pain, pain in extremity and myalgia with ibrutinib was high. Pain is a major determinant of quality of life in cancer patients undergoing chemotherapy and recognizing these may help clinicians in delivering proper supportive care.

A systematic review and meta-analysis of randomized controlled trials to evaluate the risk of fatigue and pain among patients with metastatic solid tumors treated with cabozantinib

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Background: Fatigue and pain notably contributed to the quality of life of cancer patients undergoing chemotherapy. Cabozantinib inhibits the activity of VEGFR, AXL, MET and other receptor tyrosine kinases which are essential in tumor development and progression. Yet the impact of this agent on fatigue and pain is a considerable safety concern. We undertook a systematic review and meta-analysis of randomized controlled trials (RCT) to determine these risks. Methods: MEDLINE, EMBASE databases and meeting abstracts from inception to March 2017 were queried. Phase 3 RCTs that mention fatigue, asthenia, back pain, pain in arms and legs, arthralgia, muscle spasm and bone and musculoskeletal pain as adverse effects were incorporated in the analysis. Mantel-Haenszel method was used to calculate the estimated pooled risk ratio with 95% confidence interval (CI). Results: Three phase 3 RCTs with a total of 1999 patients were eligible for analysis. Studies compared cabozantinib (C) vs everolimus, C vs placebo, C vs prednisone, were included in the analysis. The relative risks (RR) of all-grade adverse effects were as follows: fatigue, 1.34 (95% CI: 1.19- 1.50, p < 0.0001); asthenia, 1.48 (95% CI: 1.06- 2.06, p = 0.02); back pain, 1.08 (95% CI: 0.84- 1.38, p = 0.52); pain in arms and legs, 1.44 (95% CI: 1.12- 1.84, p = 0.004); arthralgia, 0.98 (95% CI: 0.70- 1.36, p = 0.91); muscle spasm, 2.59 (95% CI: 1.63- 4.12, p < 0.0001); bone pain, 1.22 (95% CI: 0.35- 4.21, p = 0.74); and musculoskeletal pain, 0.64 (95% CI: 0.42- 0.96, p = 0.03). The RR of high-grade adverse effects were as follows: fatigue, 1.84 (95% CI: 1.36- 2.48, p < 0.0001); asthenia, 2.02 (95% CI: 1.37- 2.99, p < 0.0001); back pain, 1.17 (95% CI: 0.69- 1.98, p = 0.54); pain in arms and legs, 2.93 (95% CI: 1.12- 7.63, p = 0.02); arthralgia, 0.82 (95% CI: 0.39- 1.70, p = 0.59); bone pain, 1.20 (95% CI: 0.28- 5.10, p = 0.79); and musculoskeletal pain, 1.34 (95% CI: 0.38- 4.64, p = 0.64). Conclusions: Cabozantinib increased the risk of all-grade and high-grade fatigue, asthenia and pain in arms and legs as well as all-grade muscle spasm whereas the risk of musculoskeletal pain was lower in the study arm, favoring cabozantinib.

Risk of gastrointestinal and hepatic toxicities in patients with metastatic solid tumors treated with cabozantinib: A systematic review and meta-analysis of randomized controlled trials

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Background: The vascular endothelial growth factor (VEGF) signaling pathways and the proto-oncogenes MET, KIT and RET were implied in cancer development and progression. Cabozantinib is an oral inhibitor of multiple tyrosine kinases and hence employed in many solid tumors. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of gastrointestinal (GI) and hepatic toxicities among patients with metastatic solid tumors treated with cabozantinib. Methods: MEDLINE, EMBASE databases and meeting abstracts from inception to March 2017 were queried. Phase 3 RCTs that mention GI and elevation of liver enzymes as adverse effects were incorporated in the analysis. Mantel-Haenszel method was used to calculate the estimated pooled risk ratio with 95% confidence interval (CI). Random effects model was applied. Results: We included 3 RCTs with a total of 1999 patients treated with cabozantinib for various solid tumors. The study arm used cabozantinib while the control arm utilized everolimus, placebo or prednisone. The relative risks (RR) of all-grade side effects were as follows: diarrhea, 2.39 (95% CI: 2.01 – 2.85, P < 0.0001); nausea, 1.86 (95% CI: 1.64 – 2.10, P < 0.0001); vomiting, 2.53 (95% CI: 1.60 – 3.99, P < 0.0001); stomatitis, 4.08 (95% CI: 0.55 – 30.01, P = 0.16); dysgeusia, 4.23 (95% CI: 2.30 – 7.76, P < 0.0001); elevated AST, 2.04 (95% CI: 1.12 – 3.73, P = 0.02); and elevated ALT, 1.61 (95% CI: 0.67 – 3.88, P = 0.28). The RR of high-grade side effects were as follows: diarrhea, 5.93 (95% CI: 3.43 – 10.25, P < 0.0001); nausea, 4.05 (95% CI: 1.99 – 8.23, P < 0.0001); vomiting, 2.37 (95% CI: 1.26 – 4.44, P = 0.007); stomatitis, 3.36 (95% CI: 0.45 – 24.98, P = 0.23); dysgeusia, 1.52 (95% CI: 0.15 – 14.57, P = 0.71); elevated AST, 1.70 (95% CI: 0.72 – 4.01, P = 0.22); and elevated ALT, 3.00 (95% CI: 0.60 – 14.93, P = 0.17). Conclusions: The risk of developing all-grade and high-grade diarrhea, nausea and vomiting with cabozantinib is high. Moreover, it is associated with all-grade elevated AST and dysgeusia. Timely recognition and providing good supportive care will enhance patients’ quality of life.

Incidence of palmar-plantar erythrodysesthesia and hypothyroidism in patients with metastatic cancer treated with cabozantinib: A systematic review and meta-analysis of randomized controlled trials

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Background: Cabozantinib is an oral inhibitor of multiple tyrosine kinases, including VEGFR, KIT, RET and MET, and is proven to be beneficial in different types of tumors. Nevertheless, there are noteworthy safety concerns. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of palmar-plantar erythrodysesthesia (PPE) and hypothyroidism among patients with metastatic cancer treated with cabozantinib. Methods: We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through January 31, 2017. The randomized controlled phase 3 trials that mention PPE and hypothyroidism as adverse effects were incorporated in the analysis. Mantel-Haenszel method was used to calculate the estimated pooled risk ratio (RR), and risk difference (RD) with 95% confidence interval (CI). Random effects model was applied. Results: Three phase 3 RCTs with a total of 1999 patients were eligible for analysis. Studies compared cabozantinib (C) vs everolimus, C vs placebo, C vs prednisone, were included in the analysis. All grade-PPE incidence was 499 (36.6%) in cabozantinib arm vs 26 (3.36%) in control arm with a RR of 13.998 (95% CI: 5.409 – 36.224, P < 0.0001). The absolute RD was 0.374 (95% CI: 0.258 – 0.489, P < 0.0001). High-grade PPE was reported in 93 (7.58%) in cabozantinib group vs 3 (0.39%) in control group with a RR of 12.486 (95% CI: 4.529 – 34.426, P < 0.0001). The RD was 0.080 (95% CI: 0.045 – 0.115, P < 0.0001). The overall incidence of hypothyroidism was noted in 292 (23.82%) in cabozantinib arm vs 24 (3.1%) in control arm. The pooled RR of hypothyroidism was 15.825 (95% CI: 1.229 – 203.820, P = 0.034) and RD was 0.237 (95% CI: 0.113 – 0.361, P < 0.0001). Conclusions: Our meta-analysis demonstrated that cabozantinib contributed to significant toxicity of all-grade and high-grade PPE as well as hypothyroidism. Identifying these toxicities may aide physicians in providing good supportive care and patients’ quality of life.

Risk of infectious, hematological, and gastrointestinal side effects in patients treatedwith ibrutinib: A systematic review and meta-analysis of randomized controlled trials

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Background: Bruton’s tyrosine kinase (BTK) is essential for signaling of B-cell and chemokine receptors. Ibrutinib targets BTK and has become frontier in many hematologic malignancies. We undertook systematic review and pooled analysis of randomized controlled trials (RCTs) to determine infectious, hematological and gastrointestinal risks associated with ibrutinib. Methods: We performed a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through December 31, 2016. The RCTs that mention infectious, hematological and gastrointestinal side effects as adverse effects were incorporated in the analysis. Mantel-Haenszel method was used to calculate the estimated pooled risk ratio with 95% confidence interval (CI). Results: Four RCTs with a total of 1505 patients were eligible for the analysis. Studies compared Ibrutinib (I) vs ofatumumab, I vs chlorambucil, I+ bendamustine (B)+ rituximab (R) vs placebo + B+ R and I vs temsirolimus were included in the analysis. The relative risks (RR) of all-grade side effects were as follows: infection, 1.34 (95% CI: 1.04 – 1.74; p = 0.02); pneumonia, 1.16 (95% CI: 0.82–1.66; p = 0.38); anemia, 0.77 (95% CI: 0.64 – 0.93; p = 0.007); neutropenia, 0.99 (95% CI: 0.87 – 1.14; p = 0.98); thrombocytopenia, 0.86 (95% CI: 0.71 – 1.04; p = 0.12); diarrhea, 1.74 (95% CI: 1.48 – 2.05; p < 0.0001); nausea, 0.94 (95% CI: 0.80 – 1.10; p = 0.45); and vomiting, 0.98 (95% CI 0.74 – 1.30; p = 0.93). The RR of high-grade adverse effects were as follows: febrile neutropenia, 1.32 (95% CI: 0.84 – 2.08; p = 0.21); infection, 1.20 (95% CI: 0.73 – 1.98; p = 0.45); pneumonia, 1.22 (95% CI: 0.76–1.95; p = 0.39); anemia, 0.48 (95% CI: 0.33 – 0.71; p < 0.0001); neutropenia, 0.99 (95% CI: 0.86 – 1.15; p = 0.94); thrombocytopenia, 0.61 (95% CI: 0.47 – 0.81; p = 0.001); diarrhea, 1.72 (95% CI: 0.88 – 3.34;p = 0.10); nausea, 2.56 (95% CI: 0.59 – 10.99; p = 0.20); and vomiting, 0.42 (95% CI 0.11 – 1.63; p = 0.21). Conclusions: Ibrutinib increased the risk of all-grade diarrhea and infection whereas the risks of all-grade anemia, high-grade anemia and thrombocytopenia were significantly lower in the study arm, favoring ibrutinib.

A novel function of SMC1 as a transporter of xenobiotics

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Background: Structural Maintenance of Chromosome 1 (SMC1) is a component of the cohesin complex involved in the DNA-damage repair. Studies have shown that it is overexpressed in Colon Ca, Glioblastoma ,Triple-negative breast cancer (TNBC) and contributes to their characteristic drug resistance. Because of its structural homology to the ABC-membrane transporter proteins (mediate multi-drug resistance in cancer cells by catalyzing ATP-dependent efflux of many structurally unrelated amphiphilic xenobiotics) and because of its marked over-expression in tissues of knockout mice lacking the other known transporter RLIP76 (RALBP1), the present studies were directed at determining whether SMC1 was present in plasma membrane and could function as a multi-drug transporter capable of mediating multi-drug resistance. Methods: The intracellular localization of SMC1 was performed by immunocytochemistry in fixed and live H358 cells (human non small cell lung cancer cells). We demonstrated, for the first time that SMC1 can be purified to apparent homogeneity using a GS-E affinity chromatography method. Transport activity of SMC1 was tested by reconstituting purified SMC1 into artificial liposomes, later transfected into H358 and TNBC cells with confirmed SMC1 overexpression. Accumulation and efflux of amphiphilic chemo drugs were compared to control cells. Results: Immunofixation studies demonstrated no detectable immunological cross-reactivity between SMC1 and Ralbp1.SMC1 was found in the plasma membrane ,cytosol and nucleus.The uptake of Doxorubicin and Vinblastine in transfected cells was significantly lower and were two-fold resistant to DOX as compared with controls. These cells, when treated with SMC1 antibody/antisense also confirmed increased drug cytotoxicity as well as apoptosis. Conclusions: This study provides convincing evidence for the distribution of SMC1 in the plasma membrane, cytosol, and nucleus. It functions as a drug-transporter reducing intracellular accumulation of chemotherapy drugs in cancer cells.These findings indicate a dual role in defending these from apoptosis and suggest that strategies aimed at inhibiting SMC1 could be useful in reversing intrinsic or acquired drug-resistance of cancer cells.

Abstract 3440: High-dose-rate brachytherapy as monotherapy for favorable-risk adenocarcinoma of the prostate delivered in a single 19 Gy fraction: Preliminary results of a prospective pilot study

INTRODUCTION: We evaluated the acute genitourinary (GU) and gastrointestinal (GI) toxicities, health-related quality of life (HRQOL) factors, biochemical control rates, and technical feasibility of high-dose-rate (HDR) brachytherapy as monotherapy for favorable-risk prostate cancer delivered in a single 19 Gy fraction.

METHODS: A single-institution, prospective pilot study was performed by evaluating 6 patients with low- and intermediate-risk prostate cancer treated with high-dose-rate (HDR) brachytherapy as monotherapy. Patients received a single 19 Gy fraction as HDR monotherapy without the use of a transperineal hyaluronic acid injection. Patients were assessed according to the Common Terminology Criteria for Adverse Events version 4.0 and Health-Related Quality of Life (HRQOL) questionnaires. Additionally, prostate specific antigen levels have been followed for evidence of biochemical failure.

RESULTS: All 6 patients tolerated the implant well and were all discharged home the same day. Median follow-up was 15 months with all subjects followed for at least 12 months. No grade 3, 4, or 5 toxicities were observed. Two of the 6 patients experienced grade 2 GU toxicity. One patient experienced grade 2 GI toxicity. HRQOL bowel and urinary assessments revealed peak complaints at 3 months which returned to baseline at 6 months. There have been no biochemical relapses.

CONCLUSION: This is the first study using HDR brachytherapy as monotherapy for favorable-risk prostate cancer using one implant delivered in a single 19 Gy dose in the United States. All patients demonstrated acceptable acute toxicities and were pleased with their cost-effective treatment choice.

Citation Format: Scott Dahlbeck, Chase C. Hansen, Werner deRiese, A. Robert Kagan, Carlos Torres, Maurizio Chiriva-Internati, Everardo Cobos, Jose A. Figueroa, Diane Nguyen, Lukman Tijani, Jaden D. Evans. High-dose-rate brachytherapy as monotherapy for favorable-risk adenocarcinoma of the prostate delivered in a single 19 Gy fraction: Preliminary results of a prospective pilot study. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3440. doi:10.1158/1538-7445.AM2015-3440

Reversal of liver function without exchange transfusion in sickle cell intrahepatic cholestasis

Sickle cell intrahepatic cholestasis (SCIC) is a rare but fatal complication of sickle cell disease. It is found mainly in homozygous sickle cell disease. To date, there are no standard diagnostic criteria or well-established therapeutic approaches to this condition. Herein, we report this case of a 48-year-old man with sickle cell anemia and a total bilirubin of 78.5 mg/dL without evidence of extrahepatic biliary obstruction or viral hepatitis. The patient had a hemoglobin S level of 87.9%, acute renal failure, and mild coagulopathy. Despite the disease severity, he refused exchange transfusion (ET) with packed red blood cells. He was transfused with 2 units of blood and treated mainly with supportive measures. His total bilirubin levels trended down to normal days after discharge. Multiple studies have shown a significant decrease in the mortality rate in SCIC after ET. To date, only two reported adult cases have survived SCIC without aggressive treatment. Our case is the third case that demonstrates recovery of severe SCIC without ET.

Abstract 3535: Cancer/testis antigens for immunotherapy and detection of multiple myeloma

Despite recent improvements in standard pharmacologic treatments of multiple myeloma (MM), immunotherapy may prove to be more effective due to its higher specificity and lower toxicity. Indeed, current frontline MM therapies are based on the use of drugs such as thalidomide, lenalidomide, and bortezomib, which are associated to serious side effects and undermined by the development of multidrug resistance in recurring disease. The potential for immune surveillance against tumor recurrence has been clearly exemplified by the superior effectiveness of allogeneic hematopoietic stem cell transplantation, residing in alloreactive donor T cells, compared with autologous HSCT. However, allo-HSCT has major side effects. Many of the antigens driving graft-versus-tumor activity are shared by normal host tissues. Such a setting generates graft-versus-host disease, strongly limiting complete response rates and survival. Cancer testis antigens (CTAs) are a family of proteins with testis-restricted expression that are not present, or barely present, in other tissues, but are associated with many tumors. As the testes are immunologically privileged sites lacking HLA expression, CTA are suggested to be ideal targets for immunotherapy. Here we characterized the expression of two novel MM CTA, Ropporin and AKAP4, in tumor plasma cells from patients and cell lines. Additionally, we showed that Ropporin and AKAP4 are strongly immunogenic and are therefore potential targets for effective MM vaccines. Additionally, because of their preferential expression in tumor cells, Ropporin and AKAP4 are outstanding biomarkers for tumor detection and monitoring in vivo. Similarly to other malignancies, virtually any innovative treatment for MM requires a pre-clinical assessment, which largely relies on the use of animal models to evaluate the anti-tumor potential and possible toxicities. Recently, a modified NOD strain, carrying disrupted Rag1 and the IL2-R γ chain genes (NOD-Rag1null/IL2rgnull, NRG), has been reported to tolerate higher levels of radiation compared with NOD/SCID strain and to allow for efficient engraftment of human tumors and HSC. The development of successful animal models for MM also relies on the choice of the biomarkers used to track the disease course and to identify tumor cells. Here we used the NRG strain to establish an innovative model of MM, allowing for the growth and the spread of MM cell lines and primary patients’ cells, which can be monitored by using AKAP4 as a tumor biomarker.

Citation Format: Maurizio Chiriva-Internati, Eunjee Kim, Alejandro Figueroa, Lauren Littlefield, Charles Saadeh, Raymond Wade, Vijay Giridhar, Jesse Mer, Leonardo Mirandola, Yuefei Yu, Fred Hardwicke, Nicholas D'Cunha, Lukman Tijani, Diane D. Nguyen, Jose A. Figueroa, Everardo Cobos. Cancer/testis antigens for immunotherapy and detection of multiple myeloma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3535. doi:10.1158/1538-7445.AM2013-3535

Immunological treatment options for locoregionally advanced head and neck squamous cell carcinoma

Patients with squamous cell carcinoma of the head and neck (HNSCC) are usually treated by a multimodal approach with surgery and/or radiochemotherapy as the mainstay of local-regional treatment in cases with advanced disease. Both chemotherapy and radiation therapy have the disadvantage of causing severe side effects, while the clinical outcome of patients diagnosed with HNSCC has remained essentially unchanged over the last decade. The potential of immunotherapy is still largely unexplored. Here the authors review the current status of the art and discuss the future challenges in HNSCC treatment and prevention.

Perspective for prophylaxis and treatment of cervical cancer: an immunological approach

As the second most common cause of cancer-related death in women, human papilloma virus (HPV) vaccines have been a major step in decreasing the morbidity and mortality associated with cervical cancer. An estimated 490,000 women are diagnosed with cervical cancer each year. Increasing knowledge of the HPV role in the etiology of cervical cancer has led to the development and introduction of HPV-based vaccines for active immunotherapy of cervical cancer. Immunotherapies directed at preventing HPV-persistent infections. These vaccines are already accessible for prophylaxis and in the near future, they will be available for the treatment of preexisting HPV-related neoplastic lesions.

Phase I/II study of weekly docetaxel and vinblastine in the treatment of metastatic hormone-refractory prostate carcinoma

BACKGROUND

Phase II trials have shown that taxanes have clinical activity as single agents as well as in combination with microtubule inhibitors in the treatment of hormone-refractory prostate cancer. Recent phase III trials with docetaxel have reported a survival benefit. Most trials also report significant toxicity, including thromboembolic disease. We conducted a phase I/II study to evaluate the maximum-tolerated dose, response rate, and effects on quality of life of the combination of docetaxel and vinblastine.

METHODS

Twenty men with hormone-refractory prostate cancer were treated after experiencing hormonal failure. Patients were enrolled in cohorts of three and treated with three weekly doses of docetaxel (20, 25, 30, 35, or 40 mg/m2) administered as 30-minute infusion and vinblastine (3 mg/m2) bolus. Treatment cycles were repeated every 28 days. Follow-up assessments included prostate-specific antigen level determinations, computed tomographic scans, bone scans, Brief Pain Inventory, and Functional Assessment of Cancer Therapy-Prostate Instrument (FACT-P). Toxicity was graded by National Cancer Institute common toxicity criteria.

RESULTS

The maximum tolerated dose of docetaxel was 35 mg/m2. Twelve of the 19 patients (63%; 95% CI 38%-84%) evaluable patients achieved a 50% reduction in prostate-specific antigen level that persisted for 24-80 weeks. Four of eight patients with measurable soft tissue disease had a partial response. Median time to disease progression was 50 weeks. Sixteen patients completed the Brief Pain Inventory at least three times. Twelve patients reported moderate-to-severe pain scores (>or=4) at baseline. Of these 12 patients, 11 reported that their worst pain score improved by at least two levels, and five of the 12 reported decreased opioid requirements. Seventeen patients completed the FACT-P at baseline and on at least two additional visits. Nine of these 17 (53%) reported improvement in Trial Outcome Index (sum of physical, functional, prostate subscales) by >or=6 points. Anemia was common; 12/20 patients required epoetin, and two required transfusions. Venous thrombosis developed in four patients during treatment. Only two patients discontinued treatment because of toxicity.

CONCLUSIONS

This combination of weekly docetaxel and vinblastine is effective, well tolerated, and associated with improved quality of life in most of the patients treated. Although estramustine was not given, the risk of thromboembolic disease remains significant.