Serial FDG-PET/CT for early outcome prediction in patients with metastatic colorectal cancer undergoing chemotherapy.

BACKGROUND: The study purpose was to assess the predictive value of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computerized tomography (CT) metabolic response after a single course of chemotherapy in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: FDG-PET/CT scans were carried out at baseline and on day 14 in 41 patients with unresectable mCRC treated with a biweekly regimen of chemotherapy. Metabolic nonresponse was defined by <15% decrease in FDG uptake in the dominant proportion of the patient's lesions or if a lesion was found metabolically progressive. The PET-based response was correlated with radiological response (primary end point) and patient's outcome (secondary end points). RESULTS: RECIST response rate in metabolically responding patients was 43% (10 of 23) compared with 0% (0 of 17) in nonresponding patients (P=0.002). The metabolic assessment's predictive performance for RECIST response was sensitivity 100% [95% confidence interval (CI) 69% to 100%], specificity 57% (95% CI 37% to 75%), positive predictive value 43% (95% CI 23% to 66%), and negative predictive value 100% (95% CI 80% to 100%). Comparing metabolically responding versus nonresponding patients, the hazard ratio (HR) was 0.28 (95% CI 0.10-0.76) for overall survival and 0.57 (95% CI 0.27-1.21) for progression-free survival. CONCLUSION: The metabolic response measured by FDG-PET/CT after a single course of chemotherapy in mCRC is able to identify patients who will not benefit from the treatment.

Mucolytic Agents Can Enhance HER2 Receptor Accessibility for [(89)Zr]Trastuzumab, Improving HER2 Imaging in a Mucin-Overexpressing Breast Cancer Xenograft Mouse Model.

PURPOSE: Binding of trastuzumab to HER2 receptors can be impaired by steric hindrance caused by mucin MUC4. As mucolytic drugs can breakdown disulfide bonds of mucoproteins, we checked if this approach could positively affect zirconium-89-labeled trastuzumab ([(89)Zr]T) binding/uptake. PROCEDURES: The effect of N-acetylcysteine (NAC) and MUC4 knockdown/stimulation on [(89)Zr]T binding/uptake were evaluated in MCF7(HER2-), BT474 and SKBr3(HER2+/MUC4-), and JIMT1(HER2+/MUC4+) cell lines. The results were then validated in SKBR3 and JIMT1 tumor-bearing nude mice with a microPET-CT and ex vivo analysis. RESULTS: Significant increases in [(89)Zr]T binding/uptake were observed in JIMT1 cells following MUC4 knockdown (62.4 ± 6.5%) and exposure to NAC (62.8 ± 19.4%). Compared to controls, mice treated with NAC showed a significant increase in [(89)Zr]T uptake in MUC4 tumors on microPET-CT (SUVmean (18.3 ± 4.7%), SUVmax (41.7 ± 8.4%)) and individual organ counting (37.3 ± 18.3%). In contrast, no significant differences were observed in SKBr3. CONCLUSION: NAC can enhance [(89)Zr]T accumulation and improve the HER2 imaging of MUC4-overexpressing tumors. The potential positive impact on trastuzumab-based treatment deserves further investigation.

Combination of dacarbazine and mitomycin in advanced colorectal cancer.

Twenty evaluable patients with advanced measurable colorectal cancer received 3-week courses of a combination of IV dacarbazine 300 mg/m2/day from day 1 to day 5 and IV mitomycin 2 mg/m2/day from day 1 to day 5. Fourteen of these patients had had no prior chemotherapy and received two or more courses of this two-drug regimen. None of the patients achieved complete or partial response. Severe to life-threatening myelosuppression, was encountered in patients with prior radiotherapy and or prior chemotherapy, and/or in patients with a Karnofsky score less than or equal to 70. Hematologic toxicity was mild in the other patients. Nonhematologic toxic effects were generally mild to moderate and consisted essentially in nausea and vomiting. It is concluded that in our hands the regimen selected for this trial has no significant antitumor activity in advanced colorectal cancer.

Oral versus intramuscular high-dose medroxyprogesterone acetate (HD-MPA) in advanced breast cancer. A randomized study of the Belgian Society of Medical Oncology.

Ninety postmenopausal women with advanced breast cancer were randomly assigned to be treated with HD-MPA administered either by oral route (daily dose 900 mg) or by intramuscular injections (1 g IM daily X 5 q w during 4 consecutive weeks followed by maintenance with 1 g twice weekly). Among 78 evaluable cases, most heavily pretreated, remissions, lasting for a median duration of 11 months, were more frequent on oral (8/37 = 22%) than on IM therapy (5/41 = 12%). In both arms, high estrogen receptor levels and various clinical factors were associated with higher response rates i.e., age greater than 60, Karnofsky greater than 70, light prior systemic treatment. Side-effects, consisting mainly of weight gain, hypertension and tremor occurred with equal frequency on oral or IM treatment. Five patients complained of pain at the sites of IM injections. Thus, we recommended that, whenever possible, the oral route should be preferred. During the same study, in 20 patients (11 on oral and 9 on IM therapy), blood was drawn at 0, 30, and 60 days of treatment for the assessment of MPA and hormone levels. In both arms, at 60 days, comparable levels of circulating MPA were obtained, with a very significant drop of cortisol, androstenedione, and estrone. These endocrine results, together with our clinical data, indicate that HD-MPA therapy is active on estrogen-dependent tumors with the same specificity as that of other modalities aiming to suppress the adrenal function. Its antineoplastic action in humans could be ascribed at least in part to its suppressive action on the adrenals, resulting in a severe estrogenic deprivation in postmenopausal women.

Heterogeneity of metabolic response to systemic therapy in metastatic breast cancer patients.

AIM: The aim of this retrospective study was to describe the intra-individual heterogeneity of the ¹8F-labelled fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) response among lesions in bone-dominant metastatic breast cancer patients treated with systemic therapies. PATIENTS AND METHODS: The metabolic response was analysed by comparing PET/CT scans carried out before and during a new treatment phase (n=46) in 25 bone-dominant metastatic breast cancer patients. Patients presented both bone and extra-bone metastases in 48% treatment phases. The metabolic response was analysed according to European Organization for Research and Treatment of Cancer (EORTC) criteria. A heterogeneous response was defined as the coexistence of responding and non-responding lesions within the same patient. RESULTS: The lesion-based response analysis showed a heterogeneous metabolic response in 48% of treatment phases. In the subset with both bone and extra-bone metastases (n=20), PET/CT showed discordant responses between bone and extra-bone metastases in 6/20 (30%) treatment phases. Considering all the cases included in the study, the time to progression (TTP) was longer in cases with a metabolic response compared with the cases with a metabolic non-response (P=0.02). In cases with a PET/CT non-response, TTP seemed to be lower in those with a homogeneous non-response compared with those with a heterogeneous metabolic response (P=0.07). CONCLUSION: Whole-body FDG-PET allows frequent heterogeneous responses after systemic therapy to be identified in bone-dominant metastatic breast cancer patients.

Symmetry-breaking instability of multimode vector solitons.

We show experimentally that the two-component multimode spatial optical vector soliton, i.e., a two-hump self-guided laser beam, exhibits in Kerr media a sharp space-inversion symmetry-breaking instability. The experiment is performed in a CS2 planar waveguide using the orthogonal circular polarization states of light as the two components of the vector soliton.

Hemolytic anemia in patients receiving sulfasalazine.

Hemolytic anemia is a well-recognized complication of sulfasalazine treatment. 17 of 40 (43%) patients with inflammatory bowel disease receiving sulfasalazine had evidence of hemolysis as detected by starch gel electrophoresis. Only 47% (8) of patients with hemolysis had Heinz body formation. The hemoglobin was significantly reduced in patients with hemolysis and 53% had a reticulocyte count of greater than 5%. A significant correlation was noted between hemolysis and serum sulfapyridine level, but no correlation was seen with serum sulfasalazine level. There was no significant difference in disease extent or activity in patients with hemolysis compared to those without hemolysis. Hemolysis is not a rare side-effect of sulfasalazine therapy. Heinz body formation is not invariably found in sulfasalazine-induced hemolysis.

Randomized phase II study of a combination of cisplatin (DDP), 5-fluorouracil (5-FU), and allopurinol (HPP) versus 5-FU in advanced colorectal carcinoma. An EORTC Gastrointestinal Tract Cancer Cooperative Group study.

In order to improve the therapeutic index of fluorouracil (5-FU), it has been combined with cisplatin (DDP) as synergistic agent and with allopurinol (HPP) as toxicity modulator. Patients with measurable colorectal carcinoma, previously untreated by chemotherapy, were randomized to receive either 5-FU alone 500 mg/m2 push iv days 1-5 or HPP 3 x 300 mg po, days 1-5, 5-FU 800 mg/m2 push iv, days 3-5 and DDP 50 mg/m2 d6. Treatment was repeated every 4 weeks. Of 104 patients randomized, 82 were evaluable for response and survival. Six partial responses were seen in each treatment group (15%) and the median survival time was 7 months. Hematologic toxicities were comparable in both treatment groups, with a mean nadir white blood cell count of 3500/ vs. 3800/mm3 and a mean nadir platelet count of 148,000/ vs, 203,000/mm3 for HPP-5-FU-DDP and 5-FU, respectively. This study suggests that the addition of both HPP and DDP does not improve the activity of 5-FU.