Modified FOLFOX6 plus bevacizumab with and without nivolumab for first-line treatment of metastatic colorectal cancer: phase 2 results from the CheckMate 9X8 randomized clinical trial

BACKGROUND

Standard first-line therapies for metastatic colorectal cancer (mCRC) include fluoropyrimidine-containing regimens with oxaliplatin and/or irinotecan and a biologic agent. Immunotherapy may enhance antitumor activity in combination with standard therapies in patients with mCRC. Here, we present phase 2 results of nivolumab plus standard-of-care therapy (SOC; 5-fluorouracil/leucovorin/oxaliplatin/bevacizumab) versus SOC in the first-line treatment of patients with mCRC (CheckMate 9X8).

METHODS

CheckMate 9X8 was a multicenter, open-label, randomized, phase 2/3 trial. Eligible patients were at least 18 years of age with unresectable mCRC and no prior chemotherapy for metastatic disease. Patients were randomized 2:1 to receive nivolumab 240 mg plus SOC or SOC alone every 2 weeks. The primary endpoint was progression-free survival (PFS) by blinded independent central review (BICR) per Response Evaluation Criteria in Solid Tumors V.1.1. Secondary endpoints included PFS by investigator assessment; objective response rate (ORR), disease control rate, duration of response, and time to response, all by BICR and investigator assessments; overall survival; and safety. Preplanned exploratory biomarker analyses were also performed.

RESULTS

From February 2018 through April 2019, 310 patients were enrolled, of which 195 patients were randomized to nivolumab plus SOC (n=127) or SOC (n=68). At 21.5-month minimum follow-up, PFS with nivolumab plus SOC versus SOC did not meet the prespecified threshold for statistical significance; median PFS by BICR was 11.9 months in both arms (HR, 0.81 (95% CI, 0.53 to 1.23); p=0.30). Higher PFS rates after 12 months (18 months: 28% vs 9%), higher ORR (60% vs 46%), and durable responses (median 12.9 vs 9.3 months) were observed with nivolumab plus SOC versus SOC. Grade 3-4 treatment-related adverse events were reported in 75% versus 48% of patients; no new safety signals were identified.

CONCLUSIONS

The CheckMate 9X8 trial investigating first-line nivolumab plus SOC versus SOC in patients with mCRC did not meet its primary endpoint of PFS by BICR. Nivolumab plus SOC showed numerically higher PFS rates after 12 months, a higher response rate, and more durable responses compared with SOC alone, with acceptable safety. Further investigation to identify subgroups of patients with mCRC that may benefit from nivolumab plus SOC versus SOC in the first-line setting is warranted.

TRIAL REGISTRATION NUMBER

NCT03414983.

Multi-cancer early detection test sensitivity for cancers with and without current population-level screening options

There are four solid tumors with common screening options in the average-risk population aged 21 to 75 years (breast, cervical, colorectal, and, based on personalized risk assessment, prostate), but many cancers lack recommended population screening and are often detected at advanced stages when mortality is high. Blood-based multi-cancer early detection tests have the potential to improve cancer mortality through additional population screening. Reported here is a post-hoc analysis from the third Circulating Cell-free Genome Atlas substudy to examine multi-cancer early detection test performance in solid tumors with and without population screening recommendations and in hematologic malignancies. Participants with cancer in the third Circulating Cell-free Genome Atlas substudy analysis were split into three subgroups: solid screened tumors (breast, cervical, colorectal, prostate), solid unscreened tumors, and hematologic malignancies. In this post hoc analysis, sensitivity is reported for each subgroup across all ages and those aged ⩾50 years overall, by cancer, and by clinical cancer stage. Aggregate sensitivity in the solid screened, solid unscreened, and hematologic malignancy subgroups was 34%, 66%, and 55% across all cancer stages, respectively; restricting to participants aged ⩾50 years showed similar aggregate sensitivity. Aggregate sensitivity was 27%, 53%, and 60% across stages I to III, respectively. Within the solid unscreened subgroup, aggregate sensitivity was >75% in 8/18 cancers (44%) and >50% in 13/18 (72%). This multi-cancer early detection test detected cancer signals at high (>75%) sensitivity for multiple cancers without existing population screening recommendations, suggesting its potential to complement recommended screening programs.

Clinical trial identifier: NCT02889978.

Nivolumab (NIVO) + 5-fluorouracil/leucovorin/oxaliplatin (mFOLFOX6)/bevacizumab (BEV) versus mFOLFOX6/BEV for first-line (1L) treatment of metastatic colorectal cancer (mCRC): Phase 2 results from CheckMate 9X8

8

Background: Standard 1L therapies for mCRC include a fluoropyrimidine with oxaliplatin and/or irinotecan, and a biologic agent. NIVO may enhance antitumor activity in combination with 1L standard therapies within a subset of patients (pts) with mCRC. CheckMate 9X8 evaluated NIVO + mFOLFOX6/BEV vs mFOLFOX6/BEV in 1L mCRC (NCT03414983). Methods: Adults with previously untreated, unresectable, mCRC were randomized 2:1 to NIVO 240 mg + mFOLFOX6/BEV Q2W (NIVO + standard-of-care [SOC]) or mFOLFOX6/BEV Q2W (SOC). Primary endpoint was progression-free survival (PFS) assessed by blinded independent central review (BICR) per RECIST v1.1. Key secondary endpoints included objective response rate (ORR), disease control rate (DCR), time to response (TTR), duration of response (DOR), overall survival (OS), and safety. Results: 195 pts were randomized to NIVO + SOC (n = 127) or SOC (n = 68). Median (range) follow-up was 23.7 (0–33.2) months (mo; NIVO + SOC) vs 23.2 (0–32.3) mo (SOC). Median (range) duration of therapy was 9.9 (0.1–31.8+) mo (NIVO + SOC) and 7.7 (0.1–26.7+) mo (SOC). The HR (95% CI) for PFS was 0.81 (0.53–1.23; P = 0.30), which did not meet the prespecified threshold for statistical significance (median PFS, 11.9 mo in both arms; Table). PFS rates after 12 mo were higher with NIVO + SOC vs SOC (Table). ORR was 60% (NIVO + SOC) and 46% (SOC; odds ratio 1.72 [95% CI 0.96–3.10]) and median (95% CI) DOR was 12.9 (9.0–13.1) mo (NIVO + SOC) and 9.3 (7.5–11.3) mo (SOC; Table). Rates of grade 3−4 treatment-related adverse events (TRAEs) were higher with NIVO + SOC; however, no new safety signals were identified (Table). Biomarker analyses, including tumor mutational burden and baseline CD8 levels, will be presented. Conclusions: The primary endpoint of PFS was not met; however, NIVO + SOC showed higher PFS rates after 12 mo, a higher response rate, and more durable responses compared with SOC, along with acceptable safety, in 1L mCRC. Clinical trial information: NCT03414983. [Table: see text]

Umbralisib, a Dual PI3Kδ/CK1ε Inhibitor in Patients With Relapsed or Refractory Indolent Lymphoma

PURPOSE

Phosphatidylinositol-3-kinase (PI3K) inhibitors have shown activity in relapsed or refractory (R/R) indolent non-Hodgkin lymphoma (iNHL). PI3K inhibitors have been hampered by poor long-term tolerability and toxicity, which interfere with continuous use. Umbralisib, a dual inhibitor of PI3Kδ/casein kinase-1ε, exhibits improved selectivity for PI3Kδ compared with other PI3K inhibitors. This phase IIb trial was designed to evaluate the efficacy and safety of umbralisib in patients with R/R iNHL.

PATIENTS AND METHODS

In this multicohort, open-label, phase IIb study, 208 patients with R/R marginal zone, follicular, or small lymphocytic lymphoma (MZL, FL, or SLL) unresponsive to prior treatments (≥ 1 MZL; ≥ 2 FL/SLL), including ≥ 1 anti-CD20-based therapy, were administered umbralisib 800 mg orally once daily until disease progression, unacceptable toxicity, or study withdrawal. Primary end point is overall response rate; secondary end points include time to response, duration of response, progression-free survival, and safety.

RESULTS

The median follow-up is 27.7 months (efficacy) and 21.4 months (safety). The overall response rate was 47.1%, and tumor reduction occurred in 86.4% of patients. The median time to response was 2.7-4.6 months. The median duration of response was not reached for MZL, 11.1 months for FL, and 18.3 months for SLL. Median progression-free survival was not reached for MZL, 10.6 months for FL, and 20.9 months for SLL. At least one grade ≥ 3 treatment-emergent adverse event (TEAE) was reported in 53.4% of patients. TEAEs led to umbralisib discontinuation in 32 patients (15.4%). A total of 31 patients (14.9%) discontinued because of a treatment-related adverse event. Grade ≥ 3 TEAEs reported in ≥ 10% of patients: neutropenia (11.5%) and diarrhea (10.1%). Increased ALT/AST (grade ≥ 3) occurred in 6.7%/7.2% of patients.

CONCLUSION

Umbralisib achieved meaningful clinical activity in heavily pretreated patients with iNHL. The safety profile was manageable, with a relatively low incidence of immune-mediated toxicities and adverse event-related discontinuations.

[CD20-positive T cell lymphoma: clinicopathological features of five cases]

Objective: To investigate the clinicopathological characteristics of the T cell lymphomas with CD20 expression, and to better understand this rare entity. Methods: Two-hundred cases of T-cell lymphoma diagnosed in the Department of Pathology of the Affiliated Hospital of Qingdao University from November 2016 to February 2020 were examined, and 5 cases of CD20-positive T-cell lymphomas were identified and included. Combined with clinical data and review of the literature, the clinicopathological characteristics of the disease were analyzed. Results: The five patients were all male, and had an average age of 56 years (range, 47 to 64 years). There were 2 cases of monomorphic epitheliotropic intestinal T-cell lymphoma, 2 cases of mycosis fungoides (1 case was plaque stage and the other was tumor stage) and 1 case of indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Immunohistochemistry showed that all 5 cases expressed multiple T cell markers (CD3/CD4/CD5/CD7/CD8) and only one of B cell markers (CD20). Three of the 5 cases were negative for CD20 at the first diagnosis, while CD20 was diffusely positive on the second biopsy from the recurrence or progression of the disease, without expression of CD79a or PAX5. Epstein-Barr encoding region (EBER) in situ hybridization was negative in all 5 cases. T-cell receptor gene analysis showed monoclonal rearrangement of β or/and δ chains;Ig rearrangements were all polyclonal. None of the five patients were treated with rituximab, and 4 patients survived with disease and 1 patient survived without disease at the end of follow-up. Among them, the patient with mycosis fungoides at the cancerous stage has progressed rapidly and had poor quality of life. Conclusions: CD20-positive T-cell lymphoma is extremely rare. Its prognosis is closely related to the type of T-cell lymphoma, clinical stage and initial therapeutic effect. However, the expression of CD20 indicates the recurrence or progression of the disease, and the prognosis is relatively poor. When CD3 expression is absent in T-cell lymphoma, it is easy to be misdiagnosed as B-cell lymphoma. The combination of multiple immunohistochemical antibodies and molecular detection can improve the accuracy of diagnosis.

Randomised phase II trial of gemcitabine and nab-paclitaxel with necuparanib or placebo in untreated metastatic pancreas ductal adenocarcinoma

BACKGROUND

Necuparanib, a rationally engineered low-molecular-weight heparin, combined with gemcitabine/nab-paclitaxel showed an encouraging safety and oncologic signal in a phase Ib trial. This randomised multicentre phase II trial evaluates the addition of necuparanib or placebo to gemcitabine/nab-paclitaxel in untreated metastatic pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

Eligibility included 18 years, histologically or cytologically confirmed metastatic PDAC, measurable disease and Eastern Co-Operative Oncology Group performance status of 0-1. Patients were randomly assigned to necuparanib (5 mg/kg subcutaneous injection once daily) or placebo (subcutaneous injection once daily) and gemcitabine/nab-paclitaxel on days 1, 8 and 15 of 28-day cycles. The primary end-point was median overall survival (OS), and secondary end-points included median progression-free survival, response rates and safety.

RESULTS

One-hundred ten patients were randomised, 62 to necuparanib arm and 58 to placebo arm. The futility boundary was crossed at a planned interim analysis, and the study was terminated by the Data Safety Monitoring Board. The median OS was 10.71 months (95% confidence interval [CI]: 7.95-11.96) for necuparanib arm and 9.99 months (95% CI: 7.85-12.85) for placebo arm (hazard ratio: 1.12, 95% CI: 0.66-1.89, P-value: 0.671). The necuparanib arm had a higher incidence of haematologic toxicity relative to placebo patients (83% and 70%).

CONCLUSION

The addition of necuparanib to standard of care treatment for advanced PDAC did not improve OS. Safety was acceptable. No further development of necuparanib is planned although targeting the coagulation cascade pathway remains relevant in PDAC. NCT01621243.

[Clinicopathological features of indolent T-cell lymphoproliferative disorder of the gastrointestinal tract: a report of five cases]

Objective: To investigate the clinicopathological features of indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Methods: Five cases of indolent T-cell lymphoproliferative disorder of the gastrointestinal tract from the Affiliated Hospital of Qingdao University from 2016 to 2019 were retrospectively reviewed. The clinical and pathological parameters were analyzed by combining clinical data and reviewing the available literature of 35 cases (34 cases abroad and 1 case in China). Results: There were 4 males and 1 female with a median age of 47 years (18-66 years). All patients had abdominal pain and constitutional symptoms including diarrhea, emaciation, intermittent mucous stool or oral and epiglottic ulcers. Endoscopic manifestations included multiple punctate congestion, erosion and ulcer at the terminal ileum and colorectum. Two cases had congestion and erosion of antrum and angle of stomach, and the lesions did not fuse and form tumors. Histologically, the lamina propria was expanded by a dense, medium to small lymphocyte infiltration, which was monomorphic, with slightly irregular nuclei without prominent nucleolus or lymphoepithelial lesions. There were admixed small amount of plasma cells and eosinophils. In 4 cases, immunohistochemistry showed the lesional cells were positive for CD3, CD8, TIA1, and negative for CD4, CD56, granzyme B and Ki-67 index was ≤10%. In situ hybridization showed that EBER was negative and clonal TCR gene rearrangement was detected. One consultation case was CD3(+), CD5(-) and Ki-67 index of 10%, although other indicators were not done. All five patients were treated with symptomatic support. In follow-up observation for 2 to 25 months, all patients were alive with the disease. Conclusions: Indolent T-cell lymphoproliferative disorder of the gastrointestinal tract is a newly classified monoclonal T-cell proliferative disease, with low incidence, clinical inertia and long-term survival. It has unique clinicopathological features but pathologically it is easily misdiagnosed as inflammatory bowel disease or T-cell lymphoma. Correct diagnosis is of great important clinical significance.

Neomorphic PDGFRA extracellular domain driver mutations are resistant to PDGFRA targeted therapies

Activation of platelet-derived growth factor receptor alpha (PDGFRA) by genomic aberrations contributes to tumor progression in several tumor types. In this study, we characterize 16 novel PDGFRA mutations identified from different tumor types and identify three previously uncharacterized activating mutations that promote cell survival and proliferation. PDGFRA Y288C, an extracellular domain mutation, is primarily high mannose glycosylated consistent with trapping in the endoplasmic reticulum (ER). Strikingly, PDGFRA Y288C is constitutively dimerized and phosphorylated in the absence of ligand suggesting that trapping in the ER or aberrant glycosylation is sufficient for receptor activation. Importantly, PDGFRA Y288C induces constitutive phosphorylation of Akt, ERK1/2, and STAT3. PDGFRA Y288C is resistant to PDGFR inhibitors but sensitive to PI3K/mTOR and MEK inhibitors consistent with pathway activation results. Our findings further highlight the importance of characterizing functional consequences of individual mutations for precision medicine.

Necuparanib combined with nab-paclitaxel + gemcitabine in patients with metastatic pancreatic cancer: Phase 2 results

370

Background: The Phase 1 portion of a Phase 1/2 trial of Necuparanib (“Necu”) combined with nab-paclitaxel (nabP) + gemcitabine (gem) in patients with metastatic pancreatic cancer (ClinicalTrials.gov Identifier NCT01621243) showed acceptable safety and tolerability and encouraging signals of activity and established a dose for the randomized, placebo (PBO)-controlled Phase 2 portion. Methods: In Phase 2, patients received daily s.c. injections of either 5 mg/kg Necu daily or PBO, combined with i.v. 125 mg/m2 nabP and 1000 mg/m2 gem (Days 1, 8, 15 of each 28-day cycle). The primary endpoint was overall survival (OS); other endpoints included progression-free survival (PFS), response rates, safety, and CA19.9 levels. An interim futility analysis was conducted in July 2016 once 57 deaths (50% of the target number of 114 events required for trial completion) had occurred. Results: The analysis was conducted on data from 120 randomized patients (62 Necu, 58 PBO). The Z-score for futility was -0.42 (prespecified boundary of -0.148 was crossed as actual score was lower). Median OS was Necu = 10.71 and PBO = 9.99 months; hazard ratio (HR) = 1.12 (favoring PBO); OS curves were intertwined. PFS was Necu = 5.52 and PBO = 6.93 months; HR = 0.97. RECIST response rates were comparable between arms: complete response, Necu = 0%, PBO = 3%; partial response, Necu = 26%, PBO = 26%; stable disease, Necu = 31%, PBO = 34%; disease control rate, Necu = 56%, PBO = 64%. The most common Grade 3+ adverse events (AEs) were neutropenia (Necu = 33%, PBO = 33%), thrombocytopenia (Necu = 27%, PBO = 5%), and anemia (Necu = 22%, PBO = 11%). There were lower rate of serious AEs with Necu (48%) vs. PBO (60%). Modest increases in APTT, AST, and ALT were noted following Necu relative to PBO. 23% of Necu and 5% of PBO patients were IgG positive with an anti-heparin/PF4 antibody titer of ≥ 0.4 at any time. There were no treatment differences for decreases in CA19.9. Conclusions: No new safety signals were observed and the toxicity profile was considered manageable; however, Necu in combination with nabP and gem did not show a sufficient level of efficacy in metastatic pancreatic cancer to warrant continued enrollment. Clinical trial information: NCT01621243.

BBI608-224: A phase Ib/II study of cancer stemness inhibitor napabucasin (BBI-608) administered with panitumumab in KRAS wild-type patients with metastatic colorectal cancer

677

Background: Napabucasin a first-in-class cancer stemness inhibitor in clinical development, suppresses cancer stemness by targeting Stat3-driven gene transcription. Preclinically, potent and broad-spectrum anti-cancer activity was observed in vitro and in vivo, alone and in combination with other agents. In a phase 1 study, napabucasin monotherapy was well tolerated with encouraging signs of anti-tumor activity at the RP2D of 500 mg BID. Methods: The current open-label, multi-center study includes phase II expansion in pts with refractory, K- Raswt mCRC to confirm safety and anti-tumor activity of napabucasin administered orally at 480mg BID in combination with panitumumab (6mg/kg bi-weekly). Results: 72 pts were enrolled, 48 pts were evaluable by RECIST of which 7 (15%) and 41 (85%) had 2 or >3 prior treatment lines, respectively. Of the 48 evaluable pts, 64.6% (31/48) were previously treated with an anti-EGFR agent. No new adverse events (AEs) were observed and most common AEs included grade 1/2 diarrhea, nausea, abdominal cramps, and vomiting. Among 48 pts enrolled who received RECIST evaluation, Disease Control Rate (DCR) was observed in 25 pts (52.1%) of which 3 pts achieved PR (6%) and 22 pts achieved SD (45%). Among 31 pts previously treated with anti-EGFR therapy, DCR was observed in 15 pts (48%) compared with DCR of 59% observed in 10 out of 17 anti-EGFR naïve pts receiving a scan. Conclusions: This phase II study confirmed that napabucasin can be safely combined with panitumumab at full dose and shows encouraging anti-tumor activity in pts with K- Ras wt mCRC, regardless of prior anti-EGFR exposure, suggesting that napabucasin may sensitize pts to repeat anti-EGFR therapy. Clinical trial information: NCT01776307. [Table: see text]

Leydig cells contribute to the inhibition of spermatogonial differentiation after irradiation of the rat

Irradiation with 6 Gy produces a complete block of spermatogonial differentiation in LBNF1 rats that would be permanent without treatment. Subsequent suppression of gonadotropins and testosterone (T) restores differentiation to the spermatocyte stage; however, this process requires 6 weeks. We evaluated the role of Leydig cells (LCs) in maintenance of the block in spermatogonial differentiation after exposure to radiation by specifically eliminating functional LCs with ethane dimethane sulfonate (EDS). EDS (but not another alkylating agent), given at 10 weeks after irradiation, induced spermatogonial differentiation in 24% of seminiferous tubules 2 weeks later. However, differentiation became blocked again at 4 weeks as LCs recovered. When EDS was followed by treatment with GnRH antagonist and flutamide, sustained spermatogonial differentiation was induced in >70% of tubules within 2 weeks. When EDS was followed by GnRH antagonist plus exogenous T, which also inhibits LC recovery but restores follicle stimulating hormone (FSH) levels, the spermatogonial differentiation was again rapid but transient. These results confirm that the factors that block spermatogonial differentiation are indirectly regulated by T, and probably FSH, and that adult and possibly immature LCs contribute to the production of such inhibitory factors. We tested whether insulin-like 3 (INSL3), a LC-produced protein whose expression correlated with the block in spermatogonial differentiation, was indeed responsible for the block by injecting synthetic INSL3 into the testes and knocking down its expression in vivo with siRNA. Neither treatment had any effect on spermatogonial differentiation. The Leydig cell products that contribute to the inhibition of spermatogonial differentiation in irradiated rats remain to be elucidated.

Hormone suppression with GnRH antagonist promotes spermatogenic recovery from transplanted spermatogonial stem cells in irradiated cynomolgus monkeys

Hormone suppression given before or after cytotoxic treatment stimulates the recovery of spermatogenesis from endogenous and transplanted spermatogonial stem cells (SSC) and restores fertility in rodents. To test whether the combination of hormone suppression and transplantation could enhance the recovery of spermatogenesis in primates, we irradiated (7 Gy) the testes of 12 adult cynomolgus monkeys and treated six of them with gonadotropin-releasing hormone antagonist (GnRH-ant) for 8 weeks. At the end of this treatment, we transfected cryopreserved testicular cells with green fluorescent protein-lentivirus and autologously transplanted them back into one of the testes. The only significant effect of GnRH-ant treatment on endogenous spermatogenesis was an increase in the percentage of tubules containing differentiated germ cells (tubule differentiation index; TDI) in the sham-transplanted testes of GnRH-ant-treated monkeys compared with radiation-only monkeys at 24 weeks after irradiation. Although transplantation alone after irradiation did not significantly increase the TDI, detection of lentiviral DNA in the spermatozoa of one radiation-only monkey indicated that some transplanted cells colonized the testis. However, the combination of transplantation and GnRH-ant clearly stimulated spermatogenic recovery as evidenced by several observations in the GnRH-ant-treated monkeys receiving transplantation: (i) significant increases (~20%) in the volume and weight of the testes compared with the contralateral sham-transplanted testes and/or to the transplanted testes of the radiation-only monkeys; (ii) increases in TDI compared to the transplanted testes of radiation-only monkeys at 24 weeks (9.6% vs. 2.9%; p = 0.05) and 44 weeks (16.5% vs. 6.1%, p = 0.055); (iii) detection of lentiviral sequences in the spermatozoa or testes of five of the GnRH-ant-treated monkeys and (iv) significantly higher sperm counts than in the radiation-only monkeys. Thus hormone suppression enhances spermatogenic recovery from transplanted SSC in primates and may be a useful tool in conjunction with spermatogonial transplantation to restore fertility in men after cancer treatment.

A multiplex touchdown PCR for detection of Streptococcus pneumoniae, Haemophilus influenzae type b and Mycobacterium tuberculosis complex in sputum samples

Rapid and accurate detection of Streptococcus pneumoniae (Sp), Haemophilus influenzae type b (Hib) and Mycobacterium tuberculosis complex (MTBC) in sputum by conventional methods remains problematic. Primers based on capsular polysaccharide biosynthesis gene (cpsA), the region II of the capsulation locus (cap), the insertion sequence IS6110 were designed for Sp, Hib, MTBC respectively. These primers were incorporated in a multiplex touchdown PCR assay for simultaneous detection of Sp, Hib and MTBC. The multiplex touchdown PCR assay was evaluated using standard strains and clinical sputum samples. The multiplex touchdown PCR assay showed 100% specificity in identifying Sp, Hib, MTBC from pure culture of standard strains. The sensitivities of the multiplex touchdown PCR assay were 94%, 98%, 98% for detection of Sp, Hib and MTBC respectively based on culture results while evaluated using 492 consecutive qualified clinical sputum samples; the specificities were all 100%. This highly sensitive and specific multiplex touchdown PCR assay offers a rapid and simple method for detection of Sp, Hib and MTBC in clinical sputum samples.

Pegylated liposomal doxorubicin plus carboplatin in patients with metastatic breast cancer: a phase II study

BACKGROUND

We determined the objective response rates produced by pegylated liposomal doxorubicin (PLD) plus carboplatin with/without trastuzumab (Herceptin).

PATIENTS AND METHODS

Patients with measurable disease were stratified by taxane treatment history and human epidermal growth factor receptor-2 status.

TREATMENT

PLD 30 mg/m(2) followed by carboplatin, day 1 of each 28-day cycle; human epidermal growth factor receptor-2 (HER2)-positive patients also received trastuzumab.

RESULTS

Arm 1 received PLD plus carboplatin (N = 41 arm 1a, taxane naive; N = 42 arm 1b, taxane pretreated); Arm 2 patients received PLD plus carboplatin + Herceptin (N = 46). Overall response rates: 31%, 31%, and 56%, respectively. Median overall survival durations were not reached in arm 1a and were 13 and 33 months for arms 1b and 2. Median progression-free survival: 8, 5, 10 months, respectively. Grades 3-4 treatment-related toxic effects for arms 1a, 1b, 2, respectively, were neutropenia 22%, 31%, 35%; thrombocytopenia 34%, 26%, 17%; and fatigue 2%, 14%, 13%.

CONCLUSIONS

PLD plus carboplatin has moderate antitumor activity and excellent tolerability. Herceptin and PLD plus carboplatin in HER2-positive patients have antitumor activity without significant cardiac toxicity. Toxicity results suggest that PLD can be combined with Herceptin with minimal cardiac toxicity.

A mathematical model of P53 gene regulatory networks under radiotherapy

P53, a vital anticancer gene, controls the transcription and translation of a series of genes, and implement the cell cycle arrest and cell apoptosis by regulating their complicated signal pathways. Under radiotherapy, cell can trigger internal self-defense mechanisms in fighting against genome stresses induced by acute ion radiation (IR). To simulate the investigating of cellular responding acute IR at single cell level further, we propose a model of P53 gene regulatory networks under radiotherapy. Our model can successfully implement the kinetics of double strand breaks (DSBs) generating and their repair, ataxia telangiectasia mutated (ATM) activation, as well as P53-MDM2 feedback regulating. By comparing simulations under different IR dose, we can try to find the optimal strategy in controlling of IR dose and therapy time, and provide some theoretical analysis to obtain much better outcome of radiotherapy further.

Case report: splenic sequestration and multiorgan failure as the presenting manifestation of hemoglobin SC disease

Acute splenic sequestration, a well recognized complication of the various sickle cell syndromes, is characterized by increasing splenomegaly and a sudden fall in hemoglobin concentration. In this article, the authors describe a 21-year-old woman with previously undiagnosed hemoglobin SC disease whose initial presentation was that of acute, severe splenic sequestration. Despite the severity of her illness, prompt diagnosis and appropriate therapy led to a complete recovery. The splenic sequestration in this case was apparently exacerbated by a recent hepatitis B infection. To date, this presentation of hemoglobin SC disease has not been described in the medical literature.

Sickle cell intrahepatic cholestasis: approach to a difficult problem

Sickle cell intrahepatic cholestasis is a rare but potentially fatal complication of sickle cell disease. Its characteristic features include hepatomegaly, extreme total hyperbilirubinemia, coagulopathy, and acute liver failure. Although the pathophysiology is uncertain, most reports in the medical literature indicate that the prognosis is grim. The only effective therapy that has been reported in this setting is exchange transfusion. We describe two hemoglobin SS patients with sickle cell intrahepatic cholestasis. We conclude that exchange transfusion and supportive care aimed at correction of coagulopathy, stabilization of the acute liver disease, and perhaps most important, avoidance of surgical intervention are the keys to a successful outcome.