18F-fluorodeoxyglucose positron emission tomography in the management of patients with thymic epithelial tumors

PURPOSE

There are limited data regarding the role of (18)F-fluorodeoxyglucose positron emission tomography ([(18)F]-FDG PET) imaging in management of patients with thymic epithelial tumors (TET). The primary objective of this study was to assess the usefulness of early [(18)F]-FDG PET to monitor treatment efficacy and its correlation with Response Evaluation Criteria in Solid Tumors (RECIST) in patients with TETs.

EXPERIMENTAL DESIGN

[(18)F]-FDG PET/computed tomographic (CT) scans were conducted at baseline and after 6 weeks of treatment in patients enrolled in two phase II and one phase I/II clinical trials. On the basis of data from other solid tumors, metabolic response was defined as a reduction of [(18)F]-FDG uptake by more than 30% as assessed by average standardized uptake values (SUV) of up to five most metabolically active lesions.

RESULTS

Fifty-six patients with unresectable Masaoka stage III or IV TETs were included. There was a close correlation between early metabolic response and subsequent best response using RECIST (P < 0.0001-0.0003): sensitivity and specificity for prediction of best response were 95% and 100%, respectively. Metabolic responders had significantly longer progression-free survival (median, 11.5 vs. 4.6 months; P = 0.044) and a trend toward longer overall survival (median, 31.8 vs. 18.4 months; P = 0.14) than nonresponders. [(18)F]-FDG uptake was significantly higher in thymic carcinoma than in thymoma (P = 0.0004-0.0010).

CONCLUSION

In patients with advanced TETs, early metabolic response closely correlates with outcome of therapy. [(18)F]-FDG PET may be used to monitor treatment efficacy and assess histologic differences in patients with advanced TETs.

A phase (Ph) I/II study of belinostat (Bel) in combination with cisplatin, doxorubicin, and cyclophosphamide (PAC) in the first-line treatment of advanced or recurrent thymic malignancies

7103

Background: Belinostat is a hydroxamic acid histone deacetylase (HDAC) pan-inhibitor with single agent activity in thymic malignancies. PAC has activity against thymic cancers. Synergy between Bel and several chemotherapeutic agents, including P, A, and C, has been demonstrated in preclinical models. Methods: Patients with histologically confirmed, treatment naive advanced thymic malignancies, PS<2, measurable disease, and adequate renal, hepatic and hematopoietic functions were eligible. Ph1 evaluated safety and tolerability of the combination using increasing dose levels (DL) of Bel (1000-2000 mg/m² over 48 h CIVI) and PAC (50/50/500 mg/m² IV/cycle) (3+3 dose escalation schema), administered every 21 days for no more than 6 cycles followed by optional maintenance Bel every 4 weeks. Primary end point of Ph2 is overall response rate (ORR). Results: From March 2010 to January 2012, 13 patients were enrolled [7 thymoma (T), 6 thymic carcinoma (TC); 8 in Ph1 and 5 in Ph2; median age: 49 years (range, 23-76)]. In Ph1, 6 patients were treated at DL1 (Bel 1000 mg/m2+ PAC) and 2 patients at DL2 (Bel 2000 mg/m2+ PAC). Dose Limiting Toxicities were Grade 3 nausea and diarrhea, and Grade 4 neutropenia and thrombocytopenia. Recommended phase II dose (RP2D) was set at DL1. Most common grade 3/4 treatment-related adverse events (AE) were lymphocytopenia (100%), leucopenia (85%), neutropenia (77%) thrombocytopenia (54%), anemia (38%), hypophosphatemia (38%), hypomagnesemia, hypokalemia, elevated AST, prolonged QTc and infusion-catheter related thromboembolic complications (23% each). Outcomes included one complete response (CR; T at DL1), 6 partial responses (PR; 4 T, 2 TC; 4 in Ph1, 2 in Ph2) and 6 stable disease (SD; 2 T, 4 TC; 3 each in Ph1 and Ph2). Four patients previously deemed unresectable underwent surgical resection. Conclusions: Belinostat in combination with PAC has activity in thymic malignancies with a predicable AE profile. ORR was 54% including 33% PR in the TC subgroup. RP2D of the combination has been defined. Accrual to Ph2 part and molecular profiling of patient tumors is ongoing.

Phase II study of cixutumumab (IMC-A12) in thymic malignancies

7033

Background: The IGF-1 receptor (IGF-IR) is expressed in thymoma (T) and thymic carcinoma (TC). Prolonged SD has been seen with anti-IGF-IR therapy in thymic tumors in phase I trials. Cixutumumab (C) is a fully human IgG1 monoclonal antibody (ab) that targets IGF-IR. Methods: Patients (pts) with recurrent T or TC, PS 0-2, measurable disease, and normal organ function received C at 20 mg/kg IV q3wks until progression or intolerable toxicity. Primary endpoint was response rate. Correlative studies included immune cell subset (central memory, effector memory, naïve and regulatory T cells), circulating endothelial progenitor (CEP) cell, serum IGF-1 and IGF-IR in PBMCs, anticytokine ab, and tumor mutational analysis. Results: Forty-five pts enrolled from two centers (20 female, T=33, med age 52 yrs, range, 26-86). Median number of prior systemic treatments: 3 (range, 1-11). Median number of cycles of C administered: 6 (range, 1-41). In 30 evaluable T pts there were 4 (13%) PR, 23 (77%) SD, and 3 (10%) PD. Corresponding numbers in 12 TC pts were 0, 5 (42%) and 7 (58%). Median PFS for T and TC was 40 and 9 wks respectively. C-related grade 3/4 AEs were hyperglycemia (8%), hyperuricemia, weight loss, lipase elevation, chest wall pain (5% each) and AST elevation (3%). Two pts died while on study: one due to respiratory insufficiency related to T after 5 cycles and one due to worsening myasthenia and an acute coronary event after 13 cycles. In 8 of 33 T pts autoimmune (AI) symptoms developed (4 new-onset) due to immune thrombocytopenic purpura, myositis, myocarditis, colitis, PRCA and food allergy. In the first 13 pts a trend towards increased numbers of central and effector memory T cells and a decrease in naïve T cells and CEPs was seen. High-titer anticytokine abs, including anti-IFNa, anti-IL-12, and anti-IL-17A, were found in 13/27 pts tested. No EGFR, KRAS or BRAF mutation, HER2 amplification or ALK translocations were detected in 11 tumors analyzed. Conclusions: C monotherapy is well tolerated and active in T. Accrual will continue until 37 T pts are enrolled. Activity in TC is unworthy of further investigation. CEP and immune cell subset analysis suggests therapy may impact angiogenesis and immune response. Development of AI symptoms during treatment needs further evaluation.

Cardiac toxicity and efficacy of trastuzumab combined with pertuzumab in patients with [corrected] human epidermal growth factor receptor 2-positive metastatic breast cancer

PURPOSE

To evaluate safety and efficacy of trastuzumab with pertuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer who had progressive disease on trastuzumab-based therapy.

EXPERIMENTAL DESIGN

Patients with measurable HER2(+) metastatic breast cancer, < or = 3 trastuzumab-based regimens, and left ventricular ejection fraction (LVEF) > or = 55% received 8 or 6 mg/kg trastuzumab and 840 mg pertuzumab i.v. followed by 6 mg/kg trastuzumab and 420 mg pertuzumab every 3 weeks. Cardiac evaluation and tumor response were assessed every 3 and 6 weeks, respectively.

RESULTS

Eleven patients received 64 cycles of trastuzumab plus pertuzumab. A total of 92 echocardiograms and 8 cardiac magnetic resonance imaging studies were done. With the lower limit of normal LVEF 55%, left ventricular systolic dysfunction was observed in six patients, three grade 1, two grade 2, and one grade 3 according to the National Cancer Institute Common Terminology Criteria for Adverse Events. The objective response rate was 18%. Two patients had partial responses, three had stable disease, and six had progressive disease. The median time to progression was 6 weeks. In baseline tumors from formalin-fixed paraffin-embedded primary and/or metastatic tumor biopsies, pHER2-Y1248 trended toward an increase in patients with partial response compared with those with stable disease/progressive disease (P = 0.095).

CONCLUSION

Trastuzumab plus pertuzumab may have clinical benefit in selected patients who have previously been treated with trastuzumab. Cardiac toxicity, although asymptomatic in most cases, was associated with this treatment. Further evaluation of efficacy of this combination is required to define the overall risks and benefits.

Circulating biomarkers of bevacizumab activity in patients with breast cancer

PURPOSE

Noninvasive markers of anti-vascular endothelial growth factor (VEGF) therapy are needed. Soluble vascular cell adhesion molecule (sVCAM-1), soluble VEGF receptor-2 (sVEGFR-2), and plasma VEGF levels were assessed as potential biomarkers of therapy with bevacizumab. Tumor samples were evaluated for VEGFR-2 mutations before and after bevacizumab.

EXPERIMENTAL DESIGN

Twenty-one patients with breast cancer underwent neoadjuvant treatment with bevacizumab for 1 cycle followed by 6 cycles of bevacizumab, chemotherapy, and filgrastim. Peripheral blood samples were collected at baseline, post cycles 1, 4 and 7. sVCAM-1, VEGF and sVEGFR-2 levels were measured by enzyme-linked immunosorbent assay (ELISA). Exons 17-26 of VEGFR-2 were sequenced on tissue samples from 20 patients at baseline and post cycle 1 to evaluate for tumor mutations.

RESULTS

From baseline to post cycle 1, sVCAM-1 and sVEGFR-2 values increased by a median of 180.5 ng/ml (p < 0.0001) and 1927 ng/ml respectively (p = 0.0003). Baseline VEGF, sVEGFR-2, and sVCAM-1 levels nor changes in sVEGFR-2 and sVCAM-1 levels were associated with clinical response. Median baseline sVEGFR-2 levels were 11322 ng/ml and 7524 ng/ml in patients with (n = 5) and without (n = 6) wound healing problems respectively, (p = 0.052). In 40 samples where tumor VEGFR-2 sequencing was obtained, no mutations were seen compared to the reference sequence.

CONCLUSIONS

sVCAM-1 and sVEGFR-2 values increased significantly after treatment with bevacizumab, possibly due to compensatory mechanisms secondary to VEGF inhibition. sVEGFR-2 levels were somewhat higher in patients with wound healing problems and may potentially predict patients at higher risk of this complication. There were no tumor VEGFR-2 mutations.

A Novel Case of Bisphosphonate-Related Osteonecrosis of the Torus Palatinus in a Patient with Metastatic Breast Cancer

Bisphosphonates administered orally and intravenously are used for a variety of endocrine and oncologic indications. Long-term intravenous use of bisphosphonates has been shown to cause osteonecrosis of the jaw. We report a case in which a 58-year-old woman with metastatic breast cancer received 18 doses of 4 mg intravenous zoledronic acid over a period of 16 months and developed a region of osteonecrosis on the posterior edge of a large, lobular torus palatinus. Torus palatinus, a type of maxillary exostosis, is common among postmenopausal women, and is vulnerable to blunt trauma that could predispose to osteonecrosis. Sequestrum of dead bone was removed and the site healed within 4 weeks. This case demonstrates that patients with a torus palatinus may be at high risk for osteonecrosis, and reinforces the need for good oral hygiene and frequent dental examination while receiving bisphosphonate therapy.

Phase II trial of ixabepilone, an epothilone B analog, in patients with metastatic breast cancer previously untreated with taxanes

PURPOSE

Ixabepilone is an epothilone B analog that binds to microtubules and results in microtubule stabilization and mitotic arrest. Ixabepilone was evaluated for efficacy and safety in a phase II clinical trial for women with metastatic breast cancer.

PATIENTS AND METHODS

Patients were eligible if they had not previously received treatment with a taxane and had measurable metastatic breast cancer. Ixabepilone was administered at 6 mg/m(2)/d intravenously days 1 through 5 every 3 weeks until unacceptable toxicity or disease progression. Patients underwent pretreatment and post-treatment tumor biopsies, and tissues were analyzed for acetylated alpha-tubulin, tau-1, and p53 expression when possible.

RESULTS

Twenty-three patients received 210 cycles with a median of eight cycles (range, two to 22 cycles) per patient. Thirteen patients (57%; exact 95% CI, 34.5% to 76.8%) had partial responses, six patients (26%) had stable disease, and four patients (17%) had progressive disease. Median time to progression and duration of response were 5.5 and 5.6 months, respectively. Four patients required dose reductions for neutropenia, neuropathy, or fatigue. Grade 3 or 4 toxicities included neutropenia (22%), fatigue (13%), anorexia (9%), and motor neuropathy (4%). Thirty-nine percent of patients experienced grade 1, 13% experienced grade 2, and none experienced grade 3/4 sensory neuropathy. The six patients with paired biopsies all had increases in tumor alpha-tubulin acetylation after treatment. Baseline or cycle 2 acetylated alpha-tubulin, tau-1, or p53 expression did not correlate with clinical response.

CONCLUSION

Women with metastatic breast cancer previously untreated with taxanes have a meaningful durable response to single-agent ixabepilone therapy. Minimal hematologic toxicity and no grade 3 sensory neuropathy were noted.

A prospective study of adjuvant CMF in males with node positive breast cancer: 20-year follow-up

PURPOSE

To determine the long-term overall survival of male patients with stage II node positive breast cancer treated with adjuvant chemotherapy.

PATIENTS AND METHODS

Between 1974 and 1988, 31 male breast cancer patients were prospectively enrolled on study MB-82 in the National Cancer Institute. Following mastectomy, patients were treated with 12 cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy.

RESULTS

Median patient age was 61 years (38-74 years). Twenty-one patients (68%) had 1-3 positive axillary lymph nodes while ten patients (32%) had four or more positive nodes. Estrogen receptor status was positive in 22 (71%), negative in 1 (3%), and unknown in 8 (26%) tumors. Progesterone receptor status was positive in 18 (58%), negative in 3 (10%), and unknown in 10 (32%) tumors. Median potential follow-up for all patients is 22.5 years with a median survival of 16.3 years. Twenty-one of 31 patients have died; one from a treatment-related complication, nine patients from recurrent breast cancer, five from other cancers, one from non-cancer related causes, and five from unknown causes. Ten patients remain alive at a median of 19.2 years. The overall survival probability at 10 years is 64.5% (95% CI: 46.9-78.9%), at 15 years is 51.6% (95% CI: 34.8-68%), and at 20 years is 42.4% (95% CI: 25.8-60.8%).

CONCLUSION

To our knowledge, 20-year prospective data with adjuvant chemotherapy in male breast cancer has never been reported. Adjuvant chemotherapy may benefit male breast cancer patients with positive nodes.

Phase II trial of ixabepilone, an epothilone B analog, given daily for three days every three weeks, in metastatic breast cancer

Twelve patients with metastatic breast cancer previously exposed to taxanes were treated on a Phase II trial with ixabepilone. Eligible patients had histologically confirmed metastatic breast cancer with measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST), and adequate hematopoietic, renal, and hepatic function. Ixabepilone 8 mg/m(2)/day was given intravenously daily for 3 days for the first 3-week cycle and increased to 10 mg/m(2)/day for subsequent cycles if patients did not have hematologic or other toxicity after the first cycle. Patients continued treatment until progressive disease or unacceptable toxicity. Three, 29, and 33 of 65 cycles administered were at the 7 mg/m(2), 8 mg/m(2) and 10 mg/m(2) dose levels respectively. Grade 4 leukopenia (n=1), grade 3 neutropenia (n=2), grade 2 neuropathy (n=3), and grade 2 transaminase elevation (n=2) were the most notable toxicities. Ten patients had stable disease for at least 6 weeks. No complete or partial responses were observed in 12 evaluable patients treated with ixabepilone daily for 3 days. Although ixabepilone was well-tolerated, the dose of 8-10 mg/m(2) daily for 3 days is not an effective therapy in metastatic breast cancer previously exposed to taxanes.

Changes in Neurologic Function Tests May Predict Neurotoxicity Caused by Ixabepilone

Purpose

To investigate baseline factors and neurologic function tests (NFTs) that may predict the development of grade 2 or higher peripheral neuropathy (PN) after treatment with ixabepilone, an epothilone microtubule-stabilizing agent with antitumor activity.

Patients and Methods

Advanced breast cancer patients were treated with ixabepilone (6 mg/m2) for 5 consecutive days every 3 weeks in a phase II clinical trial. Physical examinations, questionnaires, nerve conduction studies, and NFTs, including the Jebsen Test of Hand Function (JTH) and the Grooved Pegboard Test (GPT), were performed at baseline and during subsequent cycles.

Results

Forty-seven patients assessable for PN received a median of five cycles of therapy (range, one to 22 cycles). Nine of these patients developed grade 2 PN, and two developed grade 3 PN, with a median time to onset of 144 days (range, 6 to 189 days). Among these 11 patients, PN resolved in eight patients, with a median of 15 days (range, 6 to 346 days) after onset, but PN did not resolve in three patients during follow-ups at 76, 361, and 746 days after onset. GPT and changes of JTH scores at onset of PN were significantly different between patients with and without PN at comparable follow-up times (P = .006 and P = .002, respectively). Changes in GPT and JTH scores over the first two cycles were often associated with the development of PN by exploratory actuarial analysis.

Conclusion

Serious ixabepilone-induced neuropathy was relatively rare on the treatment schedule used. NFTs, such as JTH and GPT, may have utility for predicting PN, but further testing is needed.

Phase II Clinical Trial of Ixabepilone (BMS-247550), an Epothilone B Analog, in Metastatic and Locally Advanced Breast Cancer

Purpose

Ixabepilone (BMS-247550) is an epothilone B analog that stabilizes microtubules and has antitumor activity in taxane-refractory patients in phase I studies. In a phase II trial, we evaluated the efficacy and safety of ixabepilone in women with metastatic and locally advanced breast cancer.

Patients and Methods

Breast cancer patients with measurable disease who had paclitaxel and/or docetaxel as prior neoadjuvant, adjuvant, or metastatic therapy were treated with ixabepilone at 6 mg/m2/d intravenously on days 1 through 5 every 3 weeks. Levels of glutamate (glu) -terminated and acetylated α-tubulin, markers of microtubule stabilization, were detected by Western blot and by immunohistochemistry in a subset of matched pre- and post-treatment tumor biopsies.

Results

Thirty-seven patients received 153 cycles of ixabepilone. The best responses were a complete response in one patient (3%), partial responses in seven patients (19%), and stable disease in 13 patients (35%). Grade 3 and 4 toxicities included neutropenia (35%), febrile neutropenia (14%), fatigue (14%), diarrhea (11%), nausea/vomiting (5%), myalgia/arthralgia (3%), and sensory neuropathy (3%). Two patients were removed from study because of prolonged grade 2 or 3 neurotoxicity, and three patients were removed from study for other grade 3 and 4 nonhematologic toxicities. Compared with baseline levels, levels of both glu-terminated and acetylated α-tubulin were increased in tumor biopsies performed after ixabepilone therapy.

Conclusion

An objective response was seen in 22% of the patients in a population who had been previously treated with a taxane. Sensory neuropathy was mild with grade 3 neurotoxicity rarely seen. Microtubule stabilization occurred in tumor biopsies after treatment with ixabepilone.

Long-term follow-up for locally advanced and inflammatory breast cancer patients treated with multimodality therapy

PURPOSE

To determine long-term event-free (EFS) and overall survival (OS) for patients with stage III breast cancer treated with combined-modality therapy.

PATIENTS AND METHODS

Between 1980 and 1988, 107 patients with stage III breast cancer were prospectively enrolled for study at the National Cancer Institute and stratified by whether or not they had features of inflammatory breast cancer (IBC). Patients were treated to best response with cyclophosphamide, doxorubicin, methotrexate, fluorouracil, leucovorin, and hormonal synchronization with conjugated estrogens and tamoxifen. Patients with pathologic complete response received definitive radiotherapy to the breast and axilla, whereas patients with residual disease underwent mastectomy, lymph node dissection, and radiotherapy. All patients underwent six additional cycles of adjuvant chemotherapy.

RESULTS

OS and EFS were obtained with a median live patient follow-up time of 16.8 years. The 46 IBC patients had a median OS of 3.8 years and EFS of 2.3 years, compared with 12.2 and 9.0 years, respectively, in stage IIIA breast cancer patients. Fifteen-year OS survival was 20% for IBC versus 50% for stage IIIA patients and 23% for stage IIIB non-IBC. Pathologic response was not associated with improved survival for stage IIIA or IBC patients. Presence of dermal lymphatic invasion did not change the probability of survival in clinical IBC patients.

CONCLUSION

Fifteen-year follow-up of stage IIIA and inflammatory breast cancer is rarely reported; IBC patients have a poor long-term outlook.

CA 125 elevation in breast cancer: a case report and review of the literature

A 69-year-old postmenopausal woman with newly diagnosed inflammatory breast cancer was evaluated for a pelvic mass found incidentally during staging computed tomography (CT) scans. Her serum cancer antigen (CA) 125 was greater than 900 U/ml, but laparoscopic examination of the ovaries was normal. Her breast cancer was deemed metastatic by virtue of a supraclavicular lymph node, but she had no visceral or bone metastasis. She was begun on primary chemotherapy and her CA 125 normalized. CA 125 is a tumor-associated antigen that is most commonly seen in advanced ovarian cancer. It is predominantly derived from coelomic epithelium, which explains elevations in benign conditions or other malignancies. The significance of CA 125 elevations in breast cancer is uncertain. Although CA 125 production has been demonstrated in the normal breast, it has been reported most often as a marker of pleural involvement with metastatic breast cancer. Further information on CA 125 in breast cancer is required to delineate its role in the management of this disease.