Therese Smudzin

Is there a favorable subset of patients with prostate cancer who develop oligometastases

OBJECTIVE To analyze, retrospectively, the patterns and behavior of metastatic lesions in prostate cancer patients treated with external beam radiotherapy and to investigate whether patients with < or =5 lesions had an improved outcome relative to patients with >5 lesions. METHODS AND MATERIALS The treatment and outcome of 369 eligible patients with Stage T1-T3aN0-NXM0 prostate cancer were analyzed during a minimal 10-year follow-up period. All patients were treated with curative intent to a mean dose of 65 Gy. The full history of any metastatic disease was documented for each subject, including the initial site of involvement, any progression over time, and patient survival. RESULTS The overall survival rate for the 369 patients was 75% at 5 years and 45% at 10 years. The overall survival rate of patients who never developed metastases was 90% and 81% at 5 and 10 years, respectively. However, among the 74 patients (20%) who developed metastases, the survival rate at both 5 and 10 years was significantly reduced (p <0.0001). The overall survival rate for patients who developed bone metastases was 58% and 27% at 5 and 10 years, respectively, and patients with bone metastases to the pelvis fared worse compared with those with vertebral metastases. With regard to the metastatic number, patients with < or =5 metastatic lesions had superior survival rates relative to those with >5 lesions (73% and 36% at 5 and 10 years vs. 45% and 18% at 5 and 10 years, respectively; p = 0.02). In addition, both the metastasis-free survival rate and the interval measured from the date of the initial diagnosis of prostate cancer to the development of bone metastasis were statistically superior for patients with < or =5 lesions compared with patients with >5 lesions (p = 0.01 and 0.02, respectively). However, the survival rate and the interval from the date of diagnosis of bone metastasis to the time of death for patients in both groups were not significantly different, statistically (p = 0.17 and 0.27, respectively). CONCLUSIONS Patients with < or =5 metastatic sites had significantly better survival rates than patients with >5 lesions. Because existing sites of metastatic disease may be the primary sites of origin for additional metastases, our findings suggest that early detection and aggressive treatment of patients with a small number of metastatic lesions is worth testing as an approach to improving long-term survival.

Circulating IL-6 as a predictor of radiation pneumonitis.

PURPOSE We report results from a clinical research protocol investigating circulating pro-inflammatory cytokines (interleukin-6 [IL-6] and tumor necrosis factor alpha [TNFalpha]) in relation to radiation pulmonary injury. METHODS AND MATERIALS In a protocol for cytokine measurement, 25 patients had clinical follow-up longer than 12 months, and 24 had serial cytokine data. Serial plasma specimens before, during, and after thoracic radiotherapy were analyzed for IL-6 and TNFalpha using enzyme-linked immunosorbent assay (ELISA). Radiation pulmonary injury was defined using National Cancer Institute Common Toxicity Criteria. RESULTS Of the 24 patients, 6 had Grade 1 pneumonitis, and 13 had Grade 2 pneumonitis. There was no Grade 3/4 pneumonitis. Median time of radiation pneumonitis was between 8 and 12 weeks post-therapy. IL-6 levels before, during, and after thoracic radiation therapy were significantly higher in those who developed pneumonitis. In contrast, we did not detect a significant correlation between plasma TNFalpha and radiation pneumonitis. CONCLUSIONS High pretreatment plasma levels of IL-6 predisposed patients to the risk of radiation pneumonitis. Pretreatment IL-6 level may serve as a predictor for radiation pneumonitis. Serial plasma IL-6 was consistently higher for the pneumonitis group. The role of IL-6 in the cytokine cascades that promote radiation pulmonary injury deserves further investigation.

Preliminary results of a pilot study using WR-2721 before fractionated irradiation of the head and neck to reduce salivary gland dysfunction☆

PURPOSE Based on in vivo evidence of radioprotection of the salivary glands using WR-2721, a pilot study was undertaken to determine the feasibility, toxicity, and salivary function of patients receiving WR-2721, while undergoing radiation therapy to the head and neck. METHODS AND MATERIALS Patients undergoing radiation therapy for cancer of the head and neck were eligible if the major salivary glands received more than 45 Gy. WR-2721 was administered over 6 min IV, 10-15 min prior to each dose of radiation five times per week. Saliva was collected and measured prior to radiation therapy, weekly during radiation therapy, 1 month postradiation therapy, and every 3 months thereafter. Flow rates of unstimulated whole saliva, stimulated whole saliva, and stimulated parotid saliva were measured using standard techniques. 99mTc salivary scintiscans were performed prior to radiation therapy, 1 month postradiation therapy and every 3 months thereafter. Nine patients are presently enrolled on the first dose level (100 mg/m2) of this study. Eight completed per protocol, two with minor decreases of total WR-2721 doses. Two patients progressed with distant metastases soon after completion of therapy. All available data are included in the analysis. Median follow-up for all patients is 18 months. RESULTS Flow rates of unstimulated whole saliva decreased significantly during radiation therapy reaching 5.6% of baseline at 9 months postradiation therapy, subsequently recovering to 20% of baseline, then remaining stable over time. Stimulated whole salivary flow rate similarly decreased during radiation therapy and reached its nadir (11% of baseline) at 3 months postradiation therapy, improving to 27% of baseline by 2 years. The stimulated parotid flow rate decreased during radiation therapy to 1.4% of pretreatment levels. Significant recovery took place 6 months postradiation therapy and by 18 months values had recovered to 54% of baseline. 99mTc salivary scintiscans confirmed this rebound of parotid function postradiation therapy. Toxicity was minimal with the exception of one patient who received only 27% of the planned total drug dose due to grade 3 hypotension after the eighth treatment. No recovery of salivary function has been seen in this patient; flow rates remain zero in all three areas tested 21 months after radiation. CONCLUSIONS Administration of WR-2721 prior to each dose of radiation was feasible and without significant toxicity at 100 mg/m2. Salivary gland function improved over time after completion of radiation, particularly the parotid. Future directions include escalation of WR-2721 dose to 200 mg/m2 and then 300 mg/m2, and a Phase III randomized trial will be undertaken once the optimal dose is established.

Stereotactic radiosurgery for glioblastoma: retrospective analysis

PurposeThis retrospective study was done to better understand the conditions for which stereotactic radiosurgery (SRS) for glioblastoma may be efficacious.MethodsBetween 2000 and 2007, 33 patients with a pathological diagnosis of glioblastoma received SRS with the Novalis® Shaped Beam Radiosurgery system. Eighteen patients (54%) underwent salvage SRS for recurrence while 15 (45%) patients received upfront SRS following standard fractionated RT for newly diagnosed glioblastoma.ResultsThere were no RTOG grade >2 acute side effects. The median survival after SRS was 6.7 months (range 1.4 – 74.7). There was no significant difference in overall survival (from the time of initial diagnosis) with respect to the timing of SRS (p = 0.2). There was significantly better progression free survival in patients treated with SRS as consolidation versus at the time of recurrence (p = 0.04). The majority of patients failed within or at the margin of the SRS treatment volume (21/26 evaluable for recurrence).ConclusionSRS is well tolerated in the treatment of glioblastoma. As there was no difference in survival whether SRS is delivered upfront or at recurrence, the treatment for each patient should be individualized. Future studies are needed to identify patients most likely to respond to SRS.

Schedule-dependent pulsed paclitaxel radiosensitization for thoracic malignancy.

The objective of this study was to apply preclinical research of paclitaxel radiosensitization to the treatment of thoracic malignancy. Human lung cancer cell line NCI520 and epidermoid cell line A431 were investigated in vitro for radiosensitizing effects of paclitaxel. Optimal schedule of paclitaxel treatment was applied to a clinical protocol as well as off-protocol treatment of thoracic malignancy. Pulsed paclitaxel with concurrent once-daily radiation was delivered every 48 hours during the week using doses of 15 mg/m2, 20 mg/m2, or 25 mg/m2 in a phase I clinical trial of dose escalation. Preclinical data support the finding that low-dose paclitaxel is sufficient for radiosensitization. Data also support that delaying radiation is better than immediate radiation after drug treatment. Twenty-three patients have enrolled in the phase I clinical trial. Seventeen patients completed treatment (6 at 15 mg/m2; 5 at 20 mg/m2; and 6 at 25 mg/m2). Mean tumor shrinkage at 4 to 6 weeks after therapy was 82%, 84%, and 84% for dose levels I, II, and III, respectively [average primary tumor shrinkage was 83% ± 8% (95% C.I.)]. Locoregional tumor response rate was 100% [12% (2/17) complete response and 88% (15/17) partial response] with low rates of toxicity. It is concluded that pulsed low-dose paclitaxel and radiation is a very effective and well-tolerated regimen for thoracic malignancy.

A Phase 1 Trial of Eltrombopag in Patients Undergoing Stem Cell Transplantation after Total Body Irradiation

Stem cell transplantation can be associated with significant periods of thrombocytopenia, necessitating platelet transfusions and contributing to the risk of bleeding. Thrombopoietin receptor agonists have been shown to enhance platelet counts in other clinical settings, and so a phase 1 clinical trial was conducted to assess the safety, pharmacokinetics, and maximum tolerated dose of once-daily eltrombopag in patients undergoing stem cell transplantation with conditioning regimens containing total body irradiation ≥400 cGy. Eltrombopag was examined at dosage levels of 75, 150, 225, and 300 mg given orally once daily for 27 days, starting at 24 to 48 hours post-transplantation. Pharmacokinetic sampling was performed over a 24-hour period after the first dose of eltrombopag, as well as during the second week of treatment (steady-state). Nineteen patients were enrolled, 15 of whom completed protocol treatments. Three patients completed each dose level up to 225 mg, and 6 completed treatment at the highest dose of 300 mg. Four patients were replaced because drug compliance was <75% of planned doses. No dose-limiting toxicities were observed in this heterogeneous post-transplantation patient population. Common adverse events were related to standard stem cell transplantation. One episode of pulmonary embolus occurred 9 days after discontinuation of eltrombopag, and the only other thromboembolic episode was a grade 2 catheter-related clot. We conclude that up to 27 days of once-daily dosing of eltrombopag after stem cell transplantation is well tolerated.

TOXICITY PROFILE AND PHARMACOKINETIC STUDY OF A PHASE I LOW-DOSE SCHEDULE-DEPENDENT RADIOSENSITIZING PACLITAXEL CHEMORADIATION REGIMEN FOR INOPERABLE NON-SMALL-CELL LUNG CANCER

PURPOSE We report the toxicity profile and pharmacokinetic data of a schedule-dependent chemoradiation regimen using pulsed low-dose paclitaxel for radiosensitization in a Phase I study for inoperable non-small-cell lung cancer. METHODS AND MATERIALS Paclitaxel at escalating doses of 15 mg/m(2), 20 mg/m(2), and 25 mg/m(2) were infused on Monday, Wednesday, and Friday with daily chest radiation in cohorts of 6 patients. Daily radiation was delayed for maximal G2/M arrest and apoptotic effect, an observation from preclinical investigations. Plasma paclitaxel concentration was determined by high-performance liquid chromatography. RESULTS Dose-limiting toxicities included 3 of 18 patients with Grade 3 pneumonitis and 3 of 18 patients with Grade 3 esophagitis. There was no Grade 4 or 5 pneumonitis or esophagitis. There was also no Grade 3 or 4 neutropenia, thrombocytopenia, anemia or neuropathy. For Dose Levels I (15 mg/m(2)), II (20 mg/m(2)), and III (25 mg/m(2)), the mean peak plasma level was 0.23 +/- 0.06 micromol/l, 0.32 +/- 0.05 micromol/l, and 0.52 +/- 0.14 micromol/l, respectively; AUC was 0.44 +/- 0.09 micromol/l, 0.61 +/- 0.1 micromol/l, and 0.96 +/- 0.23 micromol/l, respectively; and duration of drug concentration >0.05 micromol/l (t > 0.05 micromol/l) was 1.6 +/- 0.3 h, 1.9 +/- 0.2 h, and 3.0 +/- 0.9 h, respectively. CONCLUSION Pulsed low-dose paclitaxel chemoradiation is associated with low toxicity. Pharmacokinetic data showed that plasma paclitaxel concentration >0.05 micromol/l for a minimum of 1.6 h was sufficient for effective radiosensitization.

Split-Course Palliative Radiotherapy for Advanced Non-small Cell Lung Cancer

Purpose: Palliative chest radiotherapy (RT) for lung malignancies is effective in relieving serious chest symptoms from tumor bleeding or mass effect on major airways, vessels, and nerves. Albeit an important subject, there is a lack of consensus for an optimal palliative RT regimen. We report the outcomes of a split-course palliative chest RT, a frequently used schema at our institution. Methods and Materials: Records of 140 patients treated between 1995 and 2006 were reviewed. Treatment was prescribed to an initial 25 Gy in 10 fractions through anterior-posterior/posterior-anterior beam arrangements. After a 2-week rest period, patients were selected to receive an additional 10 Gy (anterior-posterior/posterior-anterior) followed by off-cord beams to a final dose of 50 to 62.5 Gy. Symptom relief and toxicity during RT and after completion of RT were assessed from clinician notes and patient-reported symptom inventory forms. Second, the impact on survival was assessed. Results: Symptomatic relief was observed in 52 to 84% of patients with durable palliation in 58%. There were no grade 3 to 5 toxicities. Grades 1 and 2 esophagitis and pneumonitis were observed in 34 and 8% patients, respectively. Median survival was 5 months. Conclusions: A majority of patients experienced symptomatic improvement. The built-in 2-week break allowed for selection of patients for high-dose palliative radiation and balanced treatment benefits with potential side effects. Cancer survival was not adversely affected by treatments in this population with mostly advanced disease. This regimen is a viable option for patients who cannot tolerate a protracted, uninterrupted course of treatment.

PRECLINICAL AND PILOT CLINICAL STUDIES OF DOCETAXEL CHEMORADIATION FOR STAGE III NON-SMALL-CELL LUNG CANCER

PURPOSE Local and distant failure rates remain high despite aggressive chemoradiation (CRT) treatment for Stage III non-small-cell lung cancer. We conducted preclinical studies of docetaxels cytotoxic and radiosensitizing effects on lung cancer cell lines and designed a pilot study to target distant micrometastasis upfront with one-cycle induction chemotherapy, followed by low-dose radiosensitizing docetaxel CRT. METHODS AND MATERIALS A preclinical study was conducted in human lung cancer cell lines NCI 520 and A549. Cells were treated with two concentrations of docetaxel for 3 h and then irradiated immediately or after a 24-h delay. A clonogenic survival assay was conducted and analyzed for cytotoxic effects vs. radiosensitizing effects of docetaxel. A pilot clinical study was designed based on preclinical study findings. Twenty-two patients were enrolled with a median follow-up of 4 years. Induction chemotherapy consisted of 75 mg/m(2) of docetaxel and 75 mg/m(2) of cisplatin on Day 1 and 150 mg/m(2) of recombinant human granulocyte colony-stimulating factor on Days 2 through 10. Concurrent CRT was started 3 to 6 weeks later with twice-weekly docetaxel at 10 to 12 mg/m(2) and daily delayed radiation in 1.8-Gy fractions to 64.5 Gy for gross disease. RESULTS The preclinical study showed potent cytotoxic effects of docetaxel and subadditive radiosensitizing effects. Delaying radiation resulted in more cancer cell death. The pilot clinical study resulted in a median survival of 32.6 months for the entire cohort, with 3- and 5-year survival rates of 50% and 19%, respectively, and a distant metastasis-free survival rate of 61% for both 3 and 5 years. A pattern-of-failure analysis showed 75% chest failures and 36% all-distant failures. Therapy was well tolerated with Grade 3 esophagitis observed in 23% of patients. CONCLUSIONS One-cycle full-dose docetaxel/cisplatin induction chemotherapy with recombinant human granulocyte colony-stimulating factor followed by pulsed low-dose docetaxel CRT is promising with regard to its antitumor activity, low rates of distant failure, and low toxicity, suggesting that this regimen deserves further investigation.

Local control rates with five fractions of stereotactic body radiotherapy for primary lung tumors: a single institution experience of 153 consecutive patients

Background: We report our institutional experience with stereotactic body radiotherapy (SBRT) for treatment of non-small cell lung cancer (NSCLC). Methods: One hundred and fifty-three consecutive patients diagnosed with NSCLC were treated with image-guided SBRT between 2008 and 2012. Stage I patients were treated in lieu of resection, stage II-III patients were not candidates for concurrent chemoradiation and had disease amenable to SBRT and stage IV patients had oligometastatic disease. The median prescribed isocenter dose was 50 Gy in five fractions (range, 40-60 Gy) with the majority (n=121) receiving 50 Gy in five fractions. The 80% isodose line covered the planning target volume (PTV) [defined as gross tumor volume (GTV) + 7-11 mm volumetric expansion). Follow-up ranged from 1-46 months with a median of 13 months. Results: The 1- and 2-year local control (LC) rates for all patients were 92% and 85% respectively. For 111 patients with stage I NSCLC, 1- and 2-year LC was 95% and 85%, with all local recurrence (LR) occurring within 2 years. LC at 1- and 2-year was 87% for both stage II (n=19) and stage III (n=14), with all LR occurring within 10 months. For oligometastatic stage IV (n=9) patients, LC at 1- and 2-year was 71%, with all LR occurring within 5 months. Two-year LC among patients with tumors 1 cm. Tumor histology, prescribed dose, patient age, and prior radiotherapy (RT) or surgery had no significant impact on LC rates. Prior chemotherapy had a significant negative impact on LC with 1- and 2-year LC of 59%, compared to 1- and 2-year LC of 93% and 85%, respectively (P=0.015). n multivariate analysis, stage was the only significant predictor of LC. Among stage I NSCLC patients, 6 of 111 developed LR, 13 developed distant failures (of whom 5 also developed LR). Of these 111 patients, 5 died from NSCLC and 2 died from causes other than NSCLC; no patient died from treatment-related toxicity. Conclusions: SBRT plays a vital role and offers excellent LC in medically-inoperable NSCLC patients, with treatment during the early stage of the disease determined as the single most significant predictor of LC on multivariate analysis.