A lightweight hybrid vision transformer network for radar-based human activity recognition

Radar-based human activity recognition (HAR) offers a non-contact technique with privacy protection and lighting robustness for many advanced applications. Complex deep neural networks demonstrate significant performance advantages when classifying the radar micro-Doppler signals that have unique correspondences with human behavior. However, in embedded applications, the demand for lightweight and low latency poses challenges to the radar-based HAR network construction. In this paper, an efficient network based on a lightweight hybrid Vision Transformer (LH-ViT) is proposed to address the HAR accuracy and network lightweight simultaneously. This network combines the efficient convolution operations with the strength of the self-attention mechanism in ViT. Feature Pyramid architecture is applied for the multi-scale feature extraction for the micro-Doppler map. Feature enhancement is executed by the stacked Radar-ViT subsequently, in which the fold and unfold operations are added to lower the computational load of the attention mechanism. The convolution operator in the LH-ViT is replaced by the RES-SE block, an efficient structure that combines the residual learning framework with the Squeeze-and-Excitation network. Experiments based on two human activity datasets indicate our method's advantages in terms of expressiveness and computing efficiency over traditional methods.

Radar Human Activity Recognition with an Attention-Based Deep Learning Network

Radar-based human activity recognition (HAR) provides a non-contact method for many scenarios, such as human-computer interaction, smart security, and advanced surveillance with privacy protection. Feeding radar-preprocessed micro-Doppler signals into a deep learning (DL) network is a promising approach for HAR. Conventional DL algorithms can achieve high performance in terms of accuracy, but the complex network structure causes difficulty for their real-time embedded application. In this study, an efficient network with an attention mechanism is proposed. This network decouples the Doppler and temporal features of radar preprocessed signals according to the feature representation of human activity in the time-frequency domain. The Doppler feature representation is obtained in sequence using the one-dimensional convolutional neural network (1D CNN) following the sliding window. Then, HAR is realized by inputting the Doppler features into the attention-mechanism-based long short-term memory (LSTM) as a time sequence. Moreover, the activity features are effectively enhanced using the averaged cancellation method, which improves the clutter suppression effect under the micro-motion conditions. Compared with the traditional moving target indicator (MTI), the recognition accuracy is improved by about 3.7%. Experiments based on two human activity datasets confirm the superiority of our method compared to traditional methods in terms of expressiveness and computational efficiency. Specifically, our method achieves an accuracy close to 96.9% on both datasets and has a more lightweight network structure compared to algorithms with similar recognition accuracy. The method proposed in this article has great potential for real-time embedded applications of HAR.

Fast Near-Field Frequency-Diverse Computational Imaging Based on End-to-End Deep-Learning Network

The ability to sculpt complex reference waves and probe diverse radiation field patterns have facilitated the rise of metasurface antennas, while there is still a compromise between the required wide operation band and the non-overlapping characteristic of radiation field patterns. Specifically, the current computational image formation process with a classic matched filter and other sparsity-driven algorithms would inevitably face the challenge of a relatively confined scene information sampling ratio and high computational complexity. In this paper, we marry the concepts of a deep convolutional neural network with computational imaging literature. Compared with the current matched filter and compressed sensing reconstruction technique, our proposal could handle a relatively high correlation of measurement modes and low scene sampling ratio. With the delicately trained reconstruction network, point-size objects and more complicated targets can both be quickly and accurately reconstructed. In addition, the unavoidable heavy computation burden and essential large operation frequency band can be effectively mitigated. The simulated experiments with measured radiation field data verify the effectiveness of the proposed method.

Costas DFC-Based Random Stepped Wideband Waveform for Interference Countermeasure in SAR Imagery

Interference in SAR imagery will induce false targets or form a mask in specific areas to prevent accurate scene assessment. Traditional anti-jamming methods based on waveform agility require a trade-off between anti-jamming performance and imaging quality in waveform design. In this paper, we proposed a SAR ECCM scheme including a Costas DFC-based random stepped wideband waveform and corresponding imaging processing method. The waveform exhibits high flexibility against forwarding interference due to the decomposition of a wideband signal into multiple pulses with different Costas discrete frequency encoding, carrier frequency and phase modulation. Furthermore, the combination of FCDC and the imaging processing successfully overcomes the Doppler sensitivity of the proposed waveform. Extensive simulations confirmed the superiority of this waveform and processing method under different interference strategies.

Channel Phase Calibration for High-Resolution and Wide-Swath SAR Imaging with Doppler Spectrum Sharpness Optimization

Channel phase calibration is a crucial issue in high resolution and wide swath (HRWS) imagery with azimuth multi-channel synthetic aperture radar (SAR) systems. Precise phase calibration is definitely required in reconstructing the full Doppler spectrum for precise HRWS imagery without high-level ambiguities. In this paper, we propose a novel calibration for HRWS SAR imagery by optimizing the reconstructed unambiguous Doppler spectrum. The sharpness of the reconstructed Doppler spectrum is applied as the metric to measure the unambiguity quality, which is maximized to retrieve the element phase error caused by channel imbalance. Real data experiments demonstrate the performance of the proposed calibration for ambiguity suppression in HRWS SAR imagery.

Accuracy of molecular diagnostic tests for drug-resistant tuberculosis detection in China: a systematic review

OBJECTIVE: To evaluate the accuracy of molecular diagnostics for the detection of drug-resistant tuberculosis (TB) in Chinese patients.METHOD: Seven databases were searched for eligible studies that evaluated the accuracy of molecular diagnostics against drug susceptibility testing (DST) for detecting drug resistance. A bivariate random-effects meta-analysis was conducted to pool sensitivity and specificity by the index test and drug resistance type.RESULTS: A total of 159 studies were included. Compared with DST (reference standard), Xpert^® could diagnose rifampicin (RMP) resistant TB accurately, with a pooled sensitivity and pooled specificity of 92% (95%CI 90-94) and 98% (95%CI 97-98), respectively. Line-probe assays (LPAs) also performed well for RMP resistance, with a pooled sensitivity of 91% (95%CI 88-93) and pooled specificity of 98% (95%CI 96-99), but not for isoniazid (INH) or second-line drugs due to lower sensitivity (<80%). The pooled sensitivity of GeneChip^® microarrays for RMP, INH and multidrug resistance was 89% (95%CI 86-91), 79% (95%CI 75-82) and 79% (95%CI 73-84), respectively, and the specificities were all >97%. Similarly, the MeltPro^® TB/STR assay had better sensitivity and specificity for first-line drugs, varying from 87% to 89% and 97% to 98%, respectively, than for second-line drugs.CONCLUSION: The Xpert assay, LPA, GeneChip assay, and MeltPro assay are credible methods with high accuracy for RMP resistance detection, but they may not be appropriate for other anti-tuberculosis drugs due to low sensitivity.

Overexpression of miR-146a inhibits the apoptosis of hippocampal neurons of rats with cerebral hemorrhage by regulating autophagy

In this study, to investigate the effect of overexpression of miR-146a on autophagy of hippocampal neurons in rats with intracerebral hemorrhage (ICH), 72 Sprague-Dawley rats were randomly divided into the sham, ICH, miR-146a agomir, and miR-146a agomir control groups. The ICH model was constructed by injection of collagenase VII. The apoptosis of hippocampal neurons was measured by TUNEL assay. The levels of LC3 and Beclin 1 were analyzed by immunohistochemistry. Mitochondrial autophagy was examined by transmission electron microscopy. The levels of LC3A, LC3B, Beclin 1, Bax, Bcl-2, and cleaved caspase 3 were examined by Western blot. Western blot was also used to evaluate the expression of nuclear factor κB signaling pathway-related factors. To examine the effect of autophagy inhibitor (3-methyladenine (3-MA)) on miR-146a-regulated apoptotic protein expression, 30 rats were further divided into the sham, ICH, miR-146a agomir, 3-MA, and miR-146a + 3-MA groups. The levels of Bax, Bcl-2, and cleaved caspase 3 were examined by Western blot. Compared with the sham group, the nerve function scores, brain water content, the percentage of apoptotic cells, and the expression levels of LC3, Beclin 1, Bax, cleaved caspase 3, and p-P65 in the hippocampus of rats in the ICH group were all significantly increased (p < 0.05), whereas the expression levels of miR-146a, Bcl-2, and p-IκBα were markedly decreased (p < 0.05). Mitochondrial autophagy was also evident. Furthermore, compared with the ICH group, the results of the abovementioned tests in the miR-146a agomir group were reversed. The overexpression of miR-146a inhibited the autophagy of hippocampal neurons in rats with ICH.

Bayesian Compress Sensing Based Countermeasure Scheme Against the Interrupted Sampling Repeater Jamming

The interrupted sampling repeater jamming (ISRJ) is considered an efficient deception method of jamming for coherent radar detection. However, current countermeasure methods against ISRJ interference may fail in detecting weak echoes, particularly when the transmitting power of the jammer is relatively high. In this paper, we propose a novel countermeasure scheme against ISRJ based on Bayesian compress sensing (BCS), where stable target signal can be reconstructed over a relatively large range of signal-to-noise ratio (SNR) for both single target and multi-target scenarios. By deriving the ISRJ jamming strategy, only the unjammed discontinuous time segments are extracted to build a sparse target model for the reconstruction algorithm. An efficient alternate iteration is applied to optimize and solve the maximum a posteriori estimate (MAP) of the sparse targets model. Simulation results demonstrate the robustness of the proposed scheme with low SNR or large jammer ratio. Moreover, when compared with traditional FFT or greedy sparsity adaptive matching pursuit algorithm (SAMP), the proposed algorithm significantly improves on the aspects of both the grating lobe level and target detection/false detection probability.

Mesentero-axial gastric volvulus after removal of laparoscopic adjustable gastric band

Despite the decreasing popularity of gastric banding, a large number of patients still have a band in situ. Although immediate postoperative complications are relatively rare, long-term complications of gastric banding are more common but are not reported to occur after band removal. We report a case of gastric volvulus and subsequent ischaemic perforation in a patient shortly after band removal, resulting in emergency laparotomy and total gastrectomy. Severe continuing pain persisting after band deflation and even gastric band removal should be treated as an emergency and urgent investigation should not be delayed.

Concurrent use of multiple chemotherapy resistance modulators with etoposide in patients with resistant malignancies

Since chemotherapy resistance is probably multifactorial, we studied the toxicity and efficacy of adding to etoposide in sequence 5 resistance modulators in the treatment of resistant solid tumors. In cohort 1, metronidazole and ketoconazole were given with i.v. etoposide 100 mg/m(2)/day x 5 days. Because of excessive toxicity, cohort 2 received just metronidazole with etoposide, and metronidazole doses were reduced. Subsequent patient cohorts had the following drugs added to etoposide plus metronidazole: ketoconazole (cohort 3), dipyridamole (cohort 4), tamoxifen [cohort 5 (with etoposide 75 mg/m(2)/day) and 6 (with etoposide 60 mg/m(2)/day)], and cyclosporin (cohort 7). Hence, cohort 7 received daily x 5 i.v. etoposide 60 mg/m(2)/day plus 5 resistance modulators. Forty patients were treated, of whom 38 were evaluable for toxicity. Metronidazole resulted in augmentation of both central neurotoxicity and peripheral neuropathy. Sequential addition of each of dipyridamole, tamoxifen, and cyclosporin appeared to increase hematological toxicity. Some patients also experienced reversible hepatic and renal toxicity. Partial responses were seen in adrenocortical and small cell lung cancers, and minor responses with symptomatic improvement were seen in adrenocortical, small cell lung, non-small cell lung and colorectal carcinomas. Further evaluation of this approach may be warranted in patients with minimal prior chemotherapy exposure.

An NCIC-CTG phase I dose escalation pharmacokinetic study of the matrix metalloproteinase inhibitor BAY 12-9566 in combination with doxorubicin

BACKGROUND

This phase I study was performed to evaluate the safety, tolerability, and efficacy of the oral matrix metalloproteinase inhibitor BAY 12-9566 in combination with doxorubicin in patients with advanced solid tumours, and to identify the maximum tolerated dose of these agents in combination and the dose for use in subsequent studies.

PATIENTS AND METHODS

14 patients were entered onto 3 dose levels consisting of escalating doses of doxorubicin (50 mg/m(2), 60 mg/m(2) and 70 mg/m(2)) with 800 mg po bid BAY 12-9566. At all three dose levels, patients received doxorubicin alone in cycle one on day 1. Daily oral dosing with BAY 12-9566 was started on day 8 of cycle 1, and thus doxorubicin was given concurrently with BAY 12-9566 in cycle 2. Patients were continued on treatment until a dose limiting toxicity or tumour progression occurred.

RESULTS

Pharmacokinetic studies from cycles 1 and 2 from the patients treated in the first three dose levels demonstrated that the addition of BAY 12-9566 increased the AUC(0-12h) levels of doxorubicin by a median of 48%. No effects were seen on the BAY 12-9566 pharmacokinetic values. Two dose limiting toxicities were seen at the third dose level. One patient experienced grade 3 stomatitis in cycle 2, and another patient experienced grade 4 granulocytopenia in cycle 1 and grade 4 thrombocytopenia in cycle 2. Thus the maximum tolerated dose of 60 mg/m(2) was declared. These toxicities were those that would have been expected from doxorubicin alone.

CONCLUSIONS

BAY 12-9566 can be safely administered with full doses of doxorubicin without evidence of clinical interaction. The recommended dose of doxorubicin to be combined with BAY 12-9566 800 mg po b.i.d is 60 mg/m(2), however, further development of BAY 12-9566 has been abandoned.

An NCIC CTG phase I/pharmacokinetic study of the matrix metalloproteinase and angiogenesis inhibitor BAY 12-9566 in combination with 5-fluorouracil/leucovorin

BACKGROUND

This phase I study was performed to evaluate the safety, tolerability, and efficacy of the oral matrix metalloproteinase inhibitor BAY 12-9566 in combination with 5-fluorouracil/leucovorin in patients with advanced solid tumours, and to identify the maximum tolerated dose and the dose for use in future studies.

PATIENTS AND METHODS

BAY 12-9566 and 5-fluorouracil/leucovorin were administered to 17 patients in 3 cohorts. Each patient served as his/her own control, with 5-fluorouracil being given alone on days 1-5 of cycle 1. In cohort 1, BAY 12-9566 at 800 mg p.o. b.i.d. was given with 350 mg/m2 5-fluorouracil/20 mg/m2 leucovorin x 5 days q28 days. In cohort 2, the BAY 12-9566 dose was reduced to 400 mg p.o. b.i.d., with the 5-fluorouracil/leucovorin doses remaining unchanged. Finally, in cohort 3, BAY 12-9566 400 mg bid was given with 5-fluorouracil 400 mg/m2/day. Patients were continued on therapy until unacceptable toxicity or tumour progression occurred. Pharmacokinetic analyses for both BAY 12-9566 and 5-fluorouracil were performed.

RESULTS

The maximum tolerated dose was 400 mg p.o. b.i.d. BAY 12-9566 plus 5-fluorouracil/leucovorin at 400 mg/m2/day and 20 mg/m2/day, respectively. Thrombocytopenia necessitated a decrease of the dose of BAY 12-9566 by 50% from cohort 1 to cohort 2. Two dose-limiting toxicities occurred in cohort 3 consisting of neutropenic fever, and ileitis, causing severe diarrhea. Of 17 patients treated on study, 7 of 14 patients evaluable for response achieved stable disease. Pharmacokinetic analysis suggested there was no interaction between BAY 12-9566 and 5-fluorouracil.

CONCLUSIONS

BAY 12-9566 400 mg bid and 5-fluorouracil 350 mg/m2 plus leucovorin 20 mg/m2 can be co-administered. Although there is some evidence of a clinical interaction, there is no apparent pharmacokinetic interaction. Future studies with these 2 types of agents administered in combination are warranted.

A phase I study of AMD473 and docetaxel given once every 3 weeks in patients with advanced refractory cancer: a National Cancer Institute of Canada-Clinical Trials Group trial, IND 131

BACKGROUND

AMD473 (previously ZD0473) is a new-generation platinum compound with activity against a wide range of human tumour cell lines and xenografts, including carboplatin- and cisplatin-resistant lines. To assess its potential combined with a taxane, a phase I study of AMD473 and docetaxel in advanced cancer was initiated by the National Cancer Institute of Canada-Clinical Trials Group.

PATIENTS AND METHODS

Patients with advanced cancer, measurable disease, performance status Eastern Cooperative Oncology Group 0-2, no major organ dysfunction, and one or no previous taxane regimen received escalating doses of AMD473 and docetaxel every 3 weeks, with a starting dose of AMD473 80 mg/m(2) and docetaxel 60 mg/m(2).

RESULTS

Thirty-three patients enrolled on four dose levels were evaluable for toxicity and 25 patients were evaluable for response. The maximum tolerated dose was dose level 4 (AMD473 120 mg/m(2) and docetaxel 75 mg/m(2)), with grade 4 neutropenia in both minimally and heavily pretreated patients causing dose-limiting toxicity. As well at dose level 4, one patient had grade 3 vomiting despite premedication. Dose level three was expanded for both groups of patients and was defined as the recommended phase II dose at AMD473 100 mg/m(2) and docetaxel 75 mg/m(2). Non-hematologic toxicities included fatigue, diarrhoea and other mild toxicities. There was one partial response in a patient with prostate cancer and stable disease in 15 patients. No apparent pharmacokinetic interaction was noted.

CONCLUSION

AMD473 and docetaxel can be combined with a recommended phase II dose level of 100 mg/m(2) and 75 mg/m(2), respectively, given intravenously every 3 weeks. The combination has activity and should be explored in responsive tumour types.

Case-controlled study on relevant factors of adolescent sexual coercion in China

This was a case-controlled study to determine factors related to sexual coercion among adolescent abortion seekers in China. We considered the abortion-seeking women who had experienced sexual coercion as the case group and the abortion-seeking women who had never experienced sexual coercion as the control group. The results of the study indicated that the factors more likely to be related to sexual coercion include lower educational level [odds ratio (OR) = 1.55], not living with parents (OR) = 1.57, floating population (OR = 1.63), beaten by her partner (OR = 2.87), abused by her partner (OR = 1.84), multiple partners (OR = 2.10), sex after excessive drinking (OR = 5.02), younger age at first intercourse (OR = 1.68), and large difference in age between men and women (OR = 2.02). The relevant factors most likely to be associated with sexual coercion are poorly educated, not living with parents, floating population, multiple partners, younger age at first sex, and inequality between men and women.

A phase I dose escalation study of the matrix metalloproteinase inhibitor BAY 12-9566 administered orally in patients with advanced solid tumours

BACKGROUND

This phase I study was performed to evaluate the safety, tolerability, and efficacy of the oral matrix metalloproteinase inhibitor BAY 12-9566 in patients with advanced solid tumours, and to identify the maximum tolerated dose and dose for use in subsequent studies.

PATIENTS AND METHODS

BAY 12-9566 was administered to 29 patients at doses ranging from 100 mg o.d. to 1600 mg (given either 400 mg q.i.d. or 800 mg b.i.d.). Blood samples for pharmacokinetic analyses were drawn on days 1-5, day 15 and days 29 and 30. Patients were continued on daily oral treatment of BAY 12-9566 until a dose limiting toxicity or tumour progression occurred.

RESULTS

A maximum tolerated dose was not defined because plasma levels of BAY 12-9566 could not be sufficiently increased, even with escalating doses of drug. Pharmacokinetic analysis suggested that absorption was saturable at higher doses. The predominant toxicities related to drug were asymptomatic reversible effects on platelets and transaminases and mild anemia. There were no significant musculoskeletal toxicities. No objective responses were seen at the doses tested, but stable disease was observed in some patients based on tumour measurements.

CONCLUSIONS

The recommended dose of BAY 12-9566 for further studies is 800 mg b.i.d. as this dose provides maximal plasma levels that can be achieved with a convenient dosing schedule for a chronically administered oral agent.

A phase I-II study of 9-cis retinoic acid and interferon-alpha2b in patients with advanced renal-cell carcinoma: an NCIC Clinical Trials Group study

Although advanced renal-cell carcinoma (RCC) responds poorly to standard therapies, phase I-II trials have shown activity for combinations of interferon-alpha2b (IFN) with a retinoid. Alitretinoin (9-cis RA) is an endogenous retinoid with high binding affinity for both RAR and RXR receptor families. This phase I-II study enrolled 38 patients with RCC in a dose-escalation study of tolerability, pharmacokinetics (PK), and efficacy of twice daily oral 9-cis RA with subcutaneous IFN. In contrast to studies with similar doses of daily 9-cis RA, PK studies found a consistent reduction in 9-cis RA concentrations of about 50% after multiple b.i.d. doses of 30 or 50 mg/m2, independent of cotreatment with IFN. In the phase I portion, toxicities included systemic symptoms typical of IFN and biochemical abnormalities previously associated with retinoids. Two patients experienced dose-limiting toxicity at 50 mg/m2 b.i.d. of 9-cis RA, thus the recommended phase II dose was 30 mg/m2 b.i.d. One of twenty-six evaluable patients achieved a durable objective partial remission, and repeated dosing with this regimen was poorly tolerated. This combination of retinoid and interferon is not recommended for further study in RCC.

Concurrent use of multiple low dose chemotherapy agents with differing mechanisms of action as a strategy vs passive resistance: A pilot study

Resistance may be classified as active (or competitive) (due to excess amount of a factor) vs passive (or non-competitive) (due to a deficiency of a factor). Passive resistance may be important in human solid tumors. In passive resistance, the dose-response curve may be shallow, or may flatten at a relatively low dose. We hypothesized that, if passive resistance were important, it might be advantageous to use low doses of multiple concurrent chemotherapy agents with differing mechanisms of action, rather than using high doses of 2 or 3 drugs. We combined single day cisplatin 60 mg/m2, cyclophosphamide 250 mg/m2, epirubicin 40 mg/m2, paclitaxel 60 mg/m2, and vinblastine 2.5 mg/m2, with 5 days of 5-fluorouracil 200 mg/m2, folinic acid 20 mg/m2 and dexamethasone 4 mg orally q.i.d. every 3 weeks. In later cohorts, doses were escalated, and tamoxifen and verapamil were added. Twenty-three patients were entered. ECOG performance status was 1 in 15 patients and 2 in 8. Number of prior chemotherapy regimens was 0 in 4 patients, 1 in 4, 2 in 8, 3 in 4, 4 in 2, and 7 in 1. Sixteen patients had prior radiotherapy, and 3 had no prior therapy. Myelosuppression and febrile neutropenia were frequent, and 4 heavily pretreated patients died of pneumonia contracted while neutropenic. Diarrhea, nausea and vomiting, and fatigue were also prominent. Among 9 patients with non-small cell lung cancer, one had a partial remission, 4 had stable disease (including 3 with minor objective responses). Two additional non-small cell lung cancer patients also had objective tumor regression, but were coded as failures, since one had tumor progression in <6 weeks and the other died of respiratory failure (thought to be due to severe mucous plugging) one week after his first course of treatment. Among 14 patients with other tumor types, there was one partial response (esophageal carcinoma), 6 patients with stable disease for >6 weeks (including minor responses in one patient each with adenocarcinomas of kidney and breast), and 7 failures (including one patient with adenocarcinoma unknown primary who had minor tumor regression lasting 4 weeks). Despite the unacceptably high toxic death rate, median survival time was 24 weeks (range, 1 week to >104 weeks). This regimen is toxic, but survival duration is longer than would be expected in this heavily pre-treated population. Doses recommended for further study are those used in the first treatment cohort (as described above). Since myelosuppression is the major toxic effect, hemopoietic growth factors might prove helpful with this regimen.

Gemcitabine plus cisplatin, an active regimen in advanced urothelial cancer: a phase II trial of the National Cancer Institute of Canada Clinical Trials Group

PURPOSE

To evaluate the efficacy and toxicity of gemcitabine (2', 2'-difluorodeoxycytidine) plus cisplatin in previously untreated patients with advanced transitional-cell carcinoma.

PATIENTS AND METHODS

Thirty-one patients with measurable advanced transitional-cell carcinoma who had received no prior chemotherapy for metastatic disease were scheduled to receive gemcitabine 1,000 mg/m(2) intravenously over 30 minutes on days 1, 8, and 15 and cisplatin 70 mg/m(2) over 1 hour on day 2 of a 28-day cycle. Prior adjuvant or neoadjuvant therapy for locally advanced disease was allowed if this was completed more than 1 year before study entry.

RESULTS

There were six complete responses and 10 partial responses in 28 assessable patients, for an overall response rate of 16 of 28 (57%). The response rate on an intent-to-treat basis was 16 of 31 patients (52%). The median survival is 13.2 months, with 18 patients still alive at this time. Toxicity was primarily hematologic, with 12 of 31 patients (39%) having > or = grade 3 granulocytopenia and 17 of 31 (55%) having > or = grade 3 thrombocytopenia. Two patients had febrile neutropenia. All patients required a dose modification of gemcitabine at some point in their therapy; the primary reason was thrombocytopenia and/or neutropenia.

CONCLUSION

Gemcitabine plus cisplatin is an active regimen for the treatment of urothelial cancer.

Intermittent androgen suppression in the management of prostate cancer

OBJECTIVES

Intermittent androgen suppression (IAS) has been suggested as a means of attenuating the androgen deprivation syndrome in men with incurable prostate cancer. Laboratory data suggest that intermittent therapy may prolong the duration of androgen dependence.

METHODS

Since October 1993, 54 patients have entered a Phase II protocol consisting of 8 months of total androgen blockade (TAB) using leuprolide (Lupron) depot and nilutamide (Anandron) followed by an off-treatment interval of variable length. Eleven patients had biopsy-proven local failure after radiotherapy, 4 had biochemical failure, 24 had distant metastases (fewer than six axial sites on bone scan), 11 had combined local and distant failure, and 4 were treated as primary management for nodal disease. Mean prostate-specific antigen (PSA) at entry was 37 ng/mL (range 3.8 to 196). After 8 months of TAB, hormonal therapy was discontinued for those patients whose PSA was less than 4.0 ng/mL and stable or decreasing and was resumed (cycle 2) when PSA increased to greater than 10 ng/mL.

RESULTS

As of April 1 998, mean follow-up was 33 months (range 14 to 53). Patients have completed at least one, and up to five treatment cycles. The mean time to nadir PSA in cycle 1 was 20 weeks, and the mean time off was 35 weeks (31 weeks for those with metastatic disease versus 39 for local or biochemical failure). In cycle 2, the mean time to PSA nadir was 17 weeks, and the mean time off was 30 weeks (28 weeks for metastatic disease and 38 weeks for local or biochemical failure). In cycle 3, the time to PSA nadir was 19 weeks. Full testosterone data are available for 40 patients in cycle 1. Normal levels were achieved during the off-treatment interval in 73% by a mean of 18 weeks (median 9). Testosterone normalization in cycle 2 was achieved in 71% at a mean time of 17 weeks (median 14).

CONCLUSIONS

TAB can be used intermittently, and appears to be more appropriate for patients with local or biochemical failure. Testosterone recovery is not universal in the off-treatment intervals. IAS needs to be investigated in a randomized trial to determine the effect on overall survival and quality of life.

Multiple resistance modulators combined with carboplatin for resistant malignancies: a pilot study

BACKGROUND

Chemotherapy resistance is probably multifactorial; hence, we assessed the feasibility of adding to carboplatin 6 concurrent resistance modulators in 53 patients with resistant cancers.

METHODS

Pentoxifylline and dipyridamole were added to carboplatin 400 mg/m2 in cohort 1, and metronidazole was also given in cohort 2. Mannitol and saline were administered in each cohort with the theoretical objective of improving carboplatin delivery to tumors by reducing blood viscosity. Because of excessive toxicity in cohort 2, cohort 3 received the same modulators as in cohort 2 but with a reduced dose of carboplatin (200 mg/m2). Subsequent patients had the following drugs added to those in the previous cohort: novobiocin (cohort 4), tamoxifen (cohort 5), ketoconazole (cohort 6). Cohort 7 patients received the 6 cohort 6 modulators along with carboplatin 300 mg/m2.

RESULTS

Thrombocytopenia was excessive in early cohorts with a carboplatin dose of 400 mg/m2, but was minimal at lower doses. Other toxicity was generally tolerable and reversible, particularly at carboplatin doses < or = 300 mg/m2, although gastrointestinal and neurological toxicity tended to worsen as additional modulators were added. No major responses (but 4 minor responses) were seen in this patient population with heavily pretreated or primarily resistant cancers.

CONCLUSIONS

Acceptable doses for phase II studies are carboplatin 300 mg/m2, 20% mannitol 250 ml plus normal saline 500 ml over 1 hr prior to carboplatin, pentoxifylline 700 mg/m2/day p.o. from 3 days before carboplatin to cessation of therapy, dipyridamole 100 mg/m2 p.o. q6h x 6 days starting 24 hr before carboplatin, metronidazole (750 mg/m2 p.o. 12 hr and immediately before, and 24 hr after carboplatin; 250 mg/m2 suppository p.r. 12 hr and immediately before, and 6 and 24 hr after carboplatin; and 500 mg/m2 i.v. right after carboplatin), novobiocin 600 mg/m2 p.o. q12h x 6 days starting 24 hr before carboplatin, and tamoxifen 100 mg/m2/day plus ketoconazole 700 mg/m2/day x 3 days starting the day before carboplatin, with oral dexamethasone and ondansetron as antimetics.

[Treatment of cancer of the bladder in elderly patients with an intra-arterial chemotherapy and radiotherapy combination: 10-year experience]

PURPOSE

Analysis of the results obtained in elderly (75 years and older) included a phase II trial combining intra-arterial cisplatin and concurrent radiation into invasive bladder cancer.

PATIENTS AND METHODS

Thirty-five patients (28 males and 7 females) were accrued from 1985 to 1996. There were 1 Ta, 4 T2, 11 T3A, 12 T3B, 3 T4A, and 4 T4B patients. Nine had unilateral hydronephrosis and two bilateral hydronephrosis. There were 28 transurethral resections which were incomplete in 23 patients. Intra-arterial cisplatin was given as 2-4 hours infusion (60-90 mg/m2) split through both internal iliac arteries on day 1, 14, 21, and 42. Irradiation to the pelvis was started on day 14 and consisted of 40 Gy/20 fractions followed by a boost of 20 Gy/10 fractions to the tumor with margins of 2 cm.

RESULTS

Thirty (86%) completed fully the protocol. One patient died from sepsis secondary to the treatment. The tumor response was evaluable in 29 patients and complete response was observed for 27 of them. Five of these 27 patients had an isolated bladder relapse which was salvaged by cystectomy in two patients. There were 11 deaths from bladder cancer (31% of the patients): 9 from distant metastase, one from local failure, and one from treatment.

CONCLUSION

This combined modality yields excellent results with high complete response rate and good tolerance. This approach may therefore be particularly appropriate for the elderly.

Pilot study of multiple chemotherapy resistance modulators plus epirubicin in the treatment of resistant malignancies

We studied the toxicity and efficacy of adding to epirubicin five resistance modulators in the treatment of resistant solid tumors. Additional drugs were added in successive cohorts of patients, such that cohort 1 patients received two drugs along with their epirubicin, while cohort 4 patients received five modulators along with their epirubicin. Metronidazole, tamoxifen (cohort 1), dipyridamole (cohort 2), ketoconazole (cohort 3) and cyclosporin (cohort 4) were administered with epirubicin. A total of 22 patients were treated. Nausea and vomiting was usually mild to moderate. There was an unexpectedly high incidence of possible cardiac toxicity associated with treatment, although in some patients it was uncertain whether or not observed cardiac events were related to treatment. Granulocytopenia was significant in all four cohorts, but it was unclear whether it was increased by the modulators. There were two febrile neutropenic events in cohorts 1 and 2 successfully treated with antibiotics, and three septic deaths (one in each of cohorts 1, 2 and 4). It was elected to discontinue enrollment on the study prematurely in light of cardiac and other toxicity seen in the first two patients accrued in cohort 4. A single response was observed. While this approach is feasible, the observed toxicity and the difficulty patients experienced in ingesting the large number of prescribed pills will make further exploration of this approach difficult.

Gemcitabine: a promising new agent in the treatment of advanced urothelial cancer

PURPOSE

To evaluate the efficacy and toxicity of gemcitabine (2',2'-difluorodeoxycytidine) in previously untreated patients with advanced transitional cell carcinoma.

PATIENTS AND METHODS

Forty-one patients with measurable advanced transitional cell carcinoma who had received no prior chemotherapy for metastatic disease were scheduled to receive gemcitabine 1,200 mg/m2 intravenously over 30 minutes on days 1, 8, and 15 of a 28-day cycle. Prior adjuvant or neoadjuvant therapy for locally advanced disease was allowed if this was completed greater than 1 year prior to study entry. All patients were treated on an outpatient basis.

RESULTS

There were three complete responses and six partial responses seen in 37 assessable patients, for an overall response rate of nine of 37 (24.3%; 95% confidence interval, 12 to 41). Four patients remain in remission at 14, 23, 24, and 31 months. The median survival was 8 months with 17% of patients alive at 2 years. Treatment generally was well-tolerated with three patients having > or = grade 3 nonhematologic toxicity, five having grade 3 neutropenia, two having grade 3 thrombocytopenia, and two episodes of febrile neutropenia. Most patients were able to receive the drug as scheduled with the primary reason for dose reduction or dose delay being neutropenia.

CONCLUSION

Gemcitabine has promising single-agent activity against urothelial cancer with a favorable toxicity profile. Further studies in combination with other active agents are warranted.

Repeat expansion detection analysis of (CAG)n tracts in tumor cell lines, testicular tumors, and testicular cancer families

The mutational expansion of triplet repeat microsatellite sequences underlies the transmission of a number of heritable neurological disorders. However, this form of microsatellite instability has not previously been observed in association with malignant disease. Because trinucleotide expansions can dramatically alter gene expression and protein function, we hypothesized that they might occur in neoplastic cells as a mechanism through which to alter cancer genes. Accordingly, we used the repeat expansion detection technique to determine whether (CAG)n triplet repeat expansions were present in DNA from malignant cells. No expansions were observed in a survey of 20 tumor cell lines derived from neoplasms of the breast, ovary, cervix, endometrium, lung, colon, placenta, or hematopoietic system. However, we did observe expanded (CAG)n tracts in DNA from 5 of 11 testicular tumor cell lines and in 1 of 11 sporadic testicular tumors. Examination of the corresponding normal DNA, when available, revealed that some of the expansions were germline in nature. To assess the possibility that (CAG)n expansions underlie some cases of inherited testicular cancer, we also analyzed germline DNA from members of five kindreds predisposed to this malignancy. An increase in (CAG)n tract size was observed in all five families and was particularly striking in one large pedigree in which expansions were observed in three of four affected siblings. These observations raise the possibility that the germline transmission of expanded (CAG)n tracts may play a role in testicular tumorigenesis.

Paclitaxel plus hydroxyurea as second line therapy for non-small cell lung cancer

We tested paclitaxel (Taxol) and low dose hydroxyurea as second line therapy in 30 patients with non-small cell lung cancer since both drugs are active against non-small cell lung cancer in other settings, and since hydroxyurea may reverse chemotherapy resistance by disrupting double minute chromosomes. Hydroxyurea 500 mg was given orally each Monday, Wednesday, Friday starting 1 week before paclitaxel, and continuing until removal from study. Paclitaxel 135 mg/m2 was given i.v. over > or = 1 h every 3 weeks with dexamethasone, diphenhydramine, and ranitidine. Patients could have paclitaxel doses escalated to 175 mg/m2 in course 2 and to 200 mg/m2 in course 3, where tolerated. Sixteen males and 14 females were treated. All patients had previously received a single cisplatin-based chemotherapy regimen and 23 had previously received radiotherapy. Twelve patients had adenocarcinomas, six had squamous cell carcinomas, and 12 had large cell carcinomas. Eight patients had Stage IIIb cancers and 22 had Stage IV. Paclitaxel doses were 135 mg/m2 in 56 courses, 175 mg/m2 in 24, and 200 mg/m2 in 15. Treatment was well tolerated. Median granulocyte nadirs were 2.5 (x 10(9)/l) for paclitaxel 135 mg/m2, 1.8 for 175 mg/m2, and 1.3 for 200 mg/m2. No patient developed febrile neutropenia, and none required a dose reduction. Two patients had reversible anaphylaxis. Other toxicities were quite tolerable. They included fatigue, myalgias, dizziness, paresthesias, diarrhea, alopecia, mucositis, flushing, headache, swollen red hands, and anxiety. One patient had a partial remission and 15 had stable disease (including six with minor responses). Median survival was 20 (95% CI, 12-34) weeks, with 19% of patients remaining alive at 1 year from initiation of treatment. This is a well-tolerated regimen with modest activity as second line chemotherapy for patients with non-small cell lung cancer previously treated with cisplatin regimens. Higher doses would be feasible and other strategies are now being explored.

A phase II study of mitoxantrone, etoposide, and thiotepa with autologous marrow support for patients with relapsed breast cancer

To further improve the effect of high-dose chemotherapy in the treatment of locally advanced and metastatic breast cancer, we sought to develop a second active high-dose noncross-resistant regimen to use in tandem with our customary high-dose regimen of cyclophosphamide, etoposide, and cisplatin (CVP). We performed a phase II trial of high-dose mitoxantrone 30 mg/m2, etoposide 200 mg/m2 every 12 hours x 6, and thiotepa 250 mg/m2 x 3 days (MVT) in 31 patients with heavily pretreated metastatic breast cancer and one with locally advanced chemotherapy-refractory breast cancer. These patients were ineligible for high-dose CVP chemotherapy because of the amount of prior treatment and poor-response status. Of the 32 patients, 14 responded to cycle 1, did not experience any grade 4 toxicity, and received a second cycle of MVT. Overall, seven of 31 patients achieved a complete response (CR; 23%). Four of the 14, who were partial responders to the first cycle, achieved a CR after the second cycle. The overall response rate was 19 of 31 (61%) with an overall median freedom from progression of 4 to 5 months and an overall median survival of 9 months. Toxicity consisted primarily of mucositis (grade 3 or 4 in 69%). The results indicate that high-dose MVT produces significant activity, even in heavily pretreated patients. Administration of a second cycle of high-dose therapy with MVT increased the CR rate, and the morbidity and mortality from the second cycle were not greater than that for the first cycle. Because of the high incidence of grade 3 or 4 mucositis with this regimen, we are currently completing a follow-up study of high-dose mitoxantrone and thiotepa alone.

Use of recombinant human hematopoietic growth factors and autologous bone marrow transplantation to attenuate the neutropenic trough of high-dose therapy

This manuscript summarizes our experience with recombinant human granulocyte colony-stimulating factor (rhG-CSF) with high-dose Cytoxan, carmustine and etoposide (CBV in Hodgkin's disease). rhG-CSF regularly shortened the neutropenic phase following autologous bone marrow transplantation. However, this effect was more marked on the latter part of neutrophil recovery than the early part of granulocyte recovery to 100 granulocytes/microliters. The frequency of afebrile episodes was not reduced by rhG-CSF administration, but there was a tendency for the duration of fever to be shortened. Increasing doses and continuous infusion did not hasten the early part of neutrophil recovery needed to prevent the onset of infection, but was more effective than bolus infusion in increasing the rate of late neutrophil recovery. If fevers are to be prevented in this patient population, the duration of an absolute granulocyte count of less than 100/microliters will have to last only a few days. Recombinant hematopoietic growth factors alone do not hasten recovery fast enough to prevent the onset of afebrile episodes. Studies are described using both recombinant growth factor and peripheral blood and bone marrow cells to see if the neutropenic trough can be further shortened over that achievable with growth factor and autologous transplant alone.

Low-dose continuous infusion 5-fluorouracil. Evaluation in advanced breast carcinoma

Low-dose continuous infusion 5-fluorouracil (LDCI-FU) was administered to 28 women with advanced breast carcinoma. Daily doses ranged from 175 to 250 mg/m2. The LDCI-FU was delivered continuously until the appearance of toxicity and was reinstituted at a 20% dose reduction after toxicity completely resolved. Patients with a median age of 56 years and a median performance status of 60% (Karnofsky) had been previously treated with combination chemotherapy. Complete responses were observed in two patients with soft tissue metastases. Thirteen patients experienced partial responses with a median duration of response of 4+ months. Partial responses were predominantly observed in soft tissue disease; however, five patients with visceral metastases experienced partial tumor regression. Median survival for the study group was 4+ months. Hormonal receptor status did not predict response to LDCI-FU. Toxicities included stomatitis, ten patients; hand-foot syndrome, eight patients; mild leukopenia, two patients; moderate thrombocytopenia, two patients; diarrhea, three patients; ataxia, three patients. Catheter-related toxicities of sepsis and/or thrombosis occurred in six patients. Because of the demonstrated activity in previously treated patients (53% response rate), LDCI-FU should be investigated in combination chemotherapy regimens in untreated breast cancer patients.