Nivolumab in patients with metastatic DNA mismatch repair-deficient or microsatellite instability-high colorectal cancer (CheckMate 142): an open-label, multicentre, phase 2 study

BACKGROUND

Metastatic DNA mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) colorectal cancer has a poor prognosis after treatment with conventional chemotherapy and exhibits high levels of tumour neoantigens, tumour-infiltrating lymphocytes, and checkpoint regulators. All of these features are associated with the response to PD-1 blockade in other tumour types. Therefore, we aimed to study nivolumab, a PD-1 immune checkpoint inhibitor, in patients with dMMR/MSI-H metastatic colorectal cancer.

METHODS

In this ongoing, multicentre, open-label, phase 2 trial, we enrolled adults (aged ≥18 years) with histologically confirmed recurrent or metastatic colorectal cancer locally assessed as dMMR/MSI-H from 31 sites (academic centres and hospitals) in eight countries (Australia, Belgium, Canada, France, Ireland, Italy, Spain, and the USA). Eligible patients had progressed on or after, or been intolerant of, at least one previous line of treatment, including a fluoropyrimidine and oxaliplatin or irinotecan. Patients were given 3 mg/kg nivolumab every 2 weeks until disease progression, death, unacceptable toxic effects, or withdrawal from study. The primary endpoint was investigator-assessed objective response as per Response Evaluation Criteria in Solid Tumors (version 1.1). All patients who received at least one dose of study drug were included in all analyses. This trial is registered with ClinicalTrials.gov, number NCT02060188.

FINDINGS

Of the 74 patients who were enrolled between March 12, 2014, and March 16, 2016, 40 (54%) had received three or more previous treatments. At a median follow-up of 12·0 months (IQR 8·6-18·0), 23 (31·1%, 95% CI 20·8-42·9) of 74 patients achieved an investigator-assessed objective response and 51 (69%, 57-79) patients had disease control for 12 weeks or longer. Median duration of response was not yet reached; all responders were alive, and eight had responses lasting 12 months or longer (Kaplan-Meier 12-month estimate 86%, 95% CI 62-95). The most common grade 3 or 4 drug-related adverse events were increased concentrations of lipase (six [8%]) and amylase (two [3%]). 23 (31%) patients died during the study; none of these deaths were deemed to be treatment related by the investigator.

INTERPRETATION

Nivolumab provided durable responses and disease control in pre-treated patients with dMMR/MSI-H metastatic colorectal cancer, and could be a new treatment option for these patients.

FUNDING

Bristol-Myers Squibb.

Intraperitoneal cisplatin and paclitaxel in ovarian cancer

BACKGROUND

Standard chemotherapy for newly diagnosed ovarian cancer is a platinum-taxane combination. The Gynecologic Oncology Group conducted a randomized, phase 3 trial that compared intravenous paclitaxel plus cisplatin with intravenous paclitaxel plus intraperitoneal cisplatin and paclitaxel in patients with stage III ovarian cancer.

METHODS

We randomly assigned patients with stage III ovarian carcinoma or primary peritoneal carcinoma with no residual mass greater than 1.0 cm to receive 135 mg of intravenous paclitaxel per square meter of body-surface area over a 24-hour period followed by either 75 mg of intravenous cisplatin per square meter on day 2 (intravenous-therapy group) or 100 mg of intraperitoneal cisplatin per square meter on day 2 and 60 mg of intraperitoneal paclitaxel per square meter on day 8 (intraperitoneal-therapy group). Treatment was given every three weeks for six cycles. Quality of life was assessed.

RESULTS

Of 429 patients who underwent randomization, 415 were eligible. Grade 3 and 4 pain, fatigue, and hematologic, gastrointestinal, metabolic, and neurologic toxic effects were more common in the intraperitoneal-therapy group than in the intravenous-therapy group (P< or =0.001). Only 42 percent of the patients in the intraperitoneal-therapy group completed six cycles of the assigned therapy, but the median duration of progression-free survival in the intravenous-therapy and intraperitoneal-therapy groups was 18.3 and 23.8 months, respectively (P=0.05 by the log-rank test). The median duration of overall survival in the intravenous-therapy and intraperitoneal-therapy groups was 49.7 and 65.6 months, respectively (P=0.03 by the log-rank test). Quality of life was significantly worse in the intraperitoneal-therapy group before cycle 4 and three to six weeks after treatment but not one year after treatment.

CONCLUSIONS

As compared with intravenous paclitaxel plus cisplatin, intravenous paclitaxel plus intraperitoneal cisplatin and paclitaxel improves survival in patients with optimally debulked stage III ovarian cancer.

Concurrent cisplatin-based radiotherapy and chemotherapy for locally advanced cervical cancer

BACKGROUND AND METHODS

On behalf of the Gynecologic Oncology Group, we performed a randomized trial of radiotherapy in combination with three concurrent chemotherapy regimens -- cisplatin alone; cisplatin, fluorouracil, and hydroxyurea; and hydroxyurea alone -- in patients with locally advanced cervical cancer. Women with primary untreated invasive squamous-cell carcinoma, adenosquamous carcinoma, or adenocarcinoma of the cervix of stage IIB, III, or IVA, without involvement of the para-aortic lymph nodes, were enrolled. The patients had to have a leukocyte count of at least 3000 per cubic millimeter, a platelet count of at least 100,000 per cubic millimeter, a serum creatinine level no higher than 2 mg per deciliter (177 micromol per liter), and adequate hepatic function. All patients received external-beam radiotherapy according to a strict protocol. Patients were randomly assigned to receive one of three chemotherapy regimens: 40 mg of cisplatin per square meter of body-surface area per week for six weeks (group 1); 50 mg of cisplatin per square meter on days 1 and 29, followed by 4 g of fluorouracil per square meter given as a 96-hour infusion on days 1 and 29, and 2 g of oral hydroxyurea per square meter twice weekly for six weeks (group 2); or 3 g of oral hydroxyurea per square meter twice weekly for six weeks (group 3).

RESULTS

The analysis included 526 women. The median duration of follow-up was 35 months. Both groups that received cisplatin had a higher rate of progression-free survival than the group that received hydroxyurea alone (P<0.001 for both comparisons). The relative risks of progression of disease or death were 0.57 (95 percent confidence interval, 0.42 to 0.78) in group 1 and 0.55 (95 percent confidence interval, 0.40 to 0.75) in group 2, as compared with group 3. The overall survival rate was significantly higher in groups 1 and 2 than in group 3, with relative risks of death of 0.61 (95 percent confidence interval, 0.44 to 0.85) and 0.58 (95 percent confidence interval, 0.41 to 0.81), respectively.

CONCLUSIONS

Regimens of radiotherapy and chemotherapy that contain cisplatin improve the rates of survival and progression-free survival among women with locally advanced cervical cancer.

Pelvic radiation with concurrent chemotherapy compared with pelvic and para-aortic radiation for high-risk cervical cancer

BACKGROUND AND METHODS

We compared the effect of radiotherapy to a pelvic and para-aortic field with that of pelvic radiation and concurrent chemotherapy with fluorouracil and cisplatin in women with advanced cervical cancer. Between 1990 and 1997, 403 women with advanced cervical cancer confined to the pelvis (stages IIB through IVA or stage IB or IIa with a tumor diameter of at least 5 cm or involvement of pelvic lymph nodes) were randomly assigned to receive either 45 Gy of radiation to the pelvis and para-aortic lymph nodes or 45 Gy of radiation to the pelvis alone plus two cycles of fluorouracil and cisplatin (days 1 through 5 and days 22 through 26 of radiation). Patients were then to receive one or two applications of low-dose-rate intracavitary radiation, with a third cycle of chemotherapy planned for the second intracavitary procedure in the combined-therapy group.

RESULTS

Of the 403 eligible patients, 193 in each group could be evaluated. The median duration of follow-up was 43 months. Estimated cumulative rates of survival at five years were 73 percent among patients treated with radiotherapy and chemotherapy and 58 percent among patients treated with radiotherapy alone (P=0.004). Cumulative rates of disease-free survival at five years were 67 percent among patients in the combined-therapy group and 40 percent among patients in the radiotherapy group (P<0.001). The rates of both distant metastases (P<0.001) and locoregional recurrences (P<0.001) were significantly higher among patients treated with radiotherapy alone. The seriousness of side effects was similar in the two groups, with a higher rate of reversible hematologic effects in the combined-therapy group.

CONCLUSIONS

The addition of chemotherapy with fluorouracil and cisplatin to treatment with external-beam and intracavitary radiation significantly improved survival among women with locally advanced cervical cancer.

Randomized trial of cytoreduction and hyperthermic intraperitoneal chemotherapy versus systemic chemotherapy and palliative surgery in patients with peritoneal carcinomatosis of colorectal cancer

PURPOSE

To confirm the findings from uncontrolled studies that aggressive cytoreduction in combination with hyperthermic intraperitoneal chemotherapy (HIPEC) is superior to standard treatment in patients with peritoneal carcinomatosis of colorectal cancer origin.

PATIENTS AND METHODS

Between February 1998 and August 2001, 105 patients were randomly assigned to receive either standard treatment consisting of systemic chemotherapy (fluorouracil-leucovorin) with or without palliative surgery, or experimental therapy consisting of aggressive cytoreduction with HIPEC, followed by the same systemic chemotherapy regime. The primary end point was survival.

RESULTS

After a median follow-up period of 21.6 months, the median survival was 12.6 months in the standard therapy arm and 22.3 months in the experimental therapy arm (log-rank test, P =.032). The treatment-related mortality in the aggressive therapy group was 8%. Most complications from HIPEC were related to bowel leakage. Subgroup analysis of the HIPEC group showed that patients with 0 to 5 of the 7 regions of the abdominal cavity involved by tumor at the time of the cytoreduction had a significantly better survival than patients with 6 or 7 affected regions (log-rank test, P <.0001). If the cytoreduction was macroscopically complete (R-1), the median survival was also significantly better than in patients with limited (R-2a), or extensive residual disease (R-2b; log-rank test, P <.0001).

CONCLUSION

Cytoreduction followed by HIPEC improves survival in patients with peritoneal carcinomatosis of colorectal origin. However, patients with involvement of six or more regions of the abdominal cavity, or grossly incomplete cytoreduction, had still a grave prognosis.

Epidermal growth factor receptor (EGFR) signaling in cancer

The epidermal growth factor receptor (EGFR) belongs to the ErbB family of receptor tyrosine kinases (RTK). These trans-membrane proteins are activated following binding with peptide growth factors of the EGF-family of proteins. Evidence suggests that the EGFR is involved in the pathogenesis and progression of different carcinoma types. The EGFR and EGF-like peptides are often over-expressed in human carcinomas, and in vivo and in vitro studies have shown that these proteins are able to induce cell transformation. Amplification of the EGFR gene and mutations of the EGFR tyrosine kinase domain have been recently demonstrated to occur in carcinoma patients. Interestingly, both these genetic alterations of the EGFR are correlated with high probability to respond to anti-EGFR agents. However, ErbB proteins and their ligands form a complex system in which the interactions occurring between receptors and ligands affect the type and the duration of the intracellular signals that derive from receptor activation. In fact, proteins of the ErbB family form either homo- or hetero-dimers following ligand binding, each dimer showing different affinity for ligands and different signaling properties. In this regard, evidence suggests that cooperation of multiple ErbB receptors and cognate ligands is necessary to induce cell transformation. In particular, the growth and the survival of carcinoma cells appear to be sustained by a network of receptors/ligands of the ErbB family. This phenomenon is also important for therapeutic approaches, since the response to anti-EGFR agents might depend on the total level of expression of ErbB receptors and ligands in tumor cells.

Exome sequencing of head and neck squamous cell carcinoma reveals inactivating mutations in NOTCH1

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type.

Fractionated but not single-dose radiotherapy induces an immune-mediated abscopal effect when combined with anti-CTLA-4 antibody

PURPOSE

This study tested the hypothesis that the type of dose fractionation regimen determines the ability of radiotherapy to synergize with anti-CTLA-4 antibody.

EXPERIMENTAL DESIGN

TSA mouse breast carcinoma cells were injected s.c. into syngeneic mice at two separate sites, defined as a "primary" site that was irradiated and a "secondary" site outside the radiotherapy field. When both tumors were palpable, mice were randomly assigned to eight groups receiving no radiotherapy or three distinct regimens of radiotherapy (20 Gy x 1, 8 Gy x 3, or 6 Gy x 5 fractions in consecutive days) in combination or not with 9H10 monoclonal antibody against CTLA-4. Mice were followed for tumor growth/regression. Similar experiments were conducted in the MCA38 mouse colon carcinoma model.

RESULTS

In either of the two models tested, treatment with 9H10 alone had no detectable effect. Each of the radiotherapy regimens caused comparable growth delay of the primary tumors but had no effect on the secondary tumors outside the radiation field. Conversely, the combination of 9H10 and either fractionated radiotherapy regimens achieved enhanced tumor response at the primary site (P < 0.0001). Moreover, an abscopal effect, defined as a significant growth inhibition of the tumor outside the field, occurred only in mice treated with the combination of 9H10 and fractionated radiotherapy (P < 0.01). The frequency of CD8+ T cells showing tumor-specific IFN-gamma production was proportional to the inhibition of the secondary tumor.

CONCLUSIONS

Fractionated but not single-dose radiotherapy induces an abscopal effect when in combination with anti-CTLA-4 antibody in two preclinical carcinoma models.

Atezolizumab versus chemotherapy in patients with platinum-treated locally advanced or metastatic urothelial carcinoma (IMvigor211): a multicentre, open-label, phase 3 randomised controlled trial

BACKGROUND

Few options exist for patients with locally advanced or metastatic urothelial carcinoma after progression with platinum-based chemotherapy. We aimed to assess the safety and efficacy of atezolizumab (anti-programmed death-ligand 1 [PD-L1]) versus chemotherapy in this patient population.

METHODS

We conducted this multicentre, open-label, phase 3 randomised controlled trial (IMvigor211) at 217 academic medical centres and community oncology practices mainly in Europe, North America, and the Asia-Pacific region. Patients (aged ≥18 years) with metastatic urothelial carcinoma who had progressed after platinum-based chemotherapy were randomly assigned (1:1), via an interactive voice and web response system with a permuted block design (block size of four), to receive atezolizumab 1200 mg or chemotherapy (physician's choice: vinflunine 320 mg/m², paclitaxel 175 mg/m², or 75 mg/m² docetaxel) intravenously every 3 weeks. Randomisation was stratified by PD-L1 expression (expression on <1% [IC0] or 1% to <5% [IC1] of tumour-infiltrating immune cells vs ≥5% of tumour-infiltrating immune cells [IC2/3]), chemotherapy type (vinflunine vs taxanes), liver metastases (yes vs no), and number of prognostic factors (none vs one, two, or three). Patients and investigators were aware of group allocation. Patients, investigators, and the sponsor were masked to PD-L1 expression status. The primary endpoint of overall survival was tested hierarchically in prespecified populations: IC2/3, followed by IC1/2/3, followed by the intention-to-treat population. This study, which is ongoing but not recruiting participants, is registered with ClinicalTrials.gov, number NCT02302807.

FINDINGS

Between Jan 13, 2015, and Feb 15, 2016, we randomly assigned 931 patients from 198 sites to receive atezolizumab (n=467) or chemotherapy (n=464). In the IC2/3 population (n=234), overall survival did not differ significantly between patients in the atezolizumab group and those in the chemotherapy group (median 11·1 months [95% CI 8·6-15·5; n=116] vs 10·6 months [8·4-12·2; n=118]; stratified hazard ratio [HR] 0·87, 95% CI 0·63-1·21; p=0·41), thus precluding further formal statistical analysis. Confirmed objective response rates were similar between treatment groups in the IC2/3 population: 26 (23%) of 113 evaluable patients had an objective response in the atezolizumab group compared with 25 (22%) of 116 patients in the chemotherapy group. Duration of response was numerically longer in the atezolizumab group than in the chemotherapy group (median 15·9 months [95% CI 10·4 to not estimable] vs 8·3 months [5·6-13·2]; HR 0·57, 95% CI 0·26-1·26). In the intention-to-treat population, patients receiving atezolizumab had fewer grade 3-4 treatment-related adverse events than did those receiving chemotherapy (91 [20%] of 459 vs 189 [43%] of 443 patients), and fewer adverse events leading to treatment discontinuation (34 [7%] vs 78 [18%] patients).

INTERPRETATION

Atezolizumab was not associated with significantly longer overall survival than chemotherapy in patients with platinum-refractory metastatic urothelial carcinoma overexpressing PD-L1 (IC2/3). However, the safety profile for atezolizumab was favourable compared with chemotherapy, Exploratory analysis of the intention-to-treat population showed well-tolerated, durable responses in line with previous phase 2 data for atezolizumab in this setting.

FUNDING

F Hoffmann-La Roche, Genentech.

Cytoreductive surgery combined with perioperative intraperitoneal chemotherapy for the management of peritoneal carcinomatosis from colorectal cancer: a multi-institutional study

PURPOSE

The three principal studies dedicated to the natural history of peritoneal carcinomatosis (PC) from colorectal cancer consistently showed median survival ranging between 6 and 8 months. New approaches combining cytoreductive surgery and perioperative intraperitoneal chemotherapy suggest improved survival.

PATIENTS AND METHODS

A retrospective multicenter study was performed to evaluate the international experience with this combined treatment and to identify the principal prognostic indicators. All patients had cytoreductive surgery and perioperative intraperitoneal chemotherapy (intraperitoneal chemohyperthermia and/or immediate postoperative intraperitoneal chemotherapy). PC from appendiceal origin was excluded.

RESULTS

The study included 506 patients from 28 institutions operated between May 1987 and December 2002. Their median age was 51 years. The median follow-up was 53 months. The morbidity and mortality rates were 22.9% and 4%, respectively. The overall median survival was 19.2 months. Patients in whom cytoreductive surgery was complete had a median survival of 32.4 months, compared with 8.4 months for patients in whom complete cytoreductive surgery was not possible (P <.001). Positive independent prognostic indicators by multivariate analysis were complete cytoreduction, treatment by a second procedure, limited extent of PC, age less than 65 years, and use of adjuvant chemotherapy. The use of neoadjuvant chemotherapy, lymph node involvement, presence of liver metastasis, and poor histologic differentiation were negative independent prognostic indicators.

CONCLUSION

The therapeutic approach combining cytoreductive surgery with perioperative intraperitoneal chemotherapy achieved long-term survival in a selected group of patients with PC from colorectal origin with acceptable morbidity and mortality. The complete cytoreductive surgery was the most important prognostic indicator.

Recurrent epithelial ovarian carcinoma: a randomized phase III study of pegylated liposomal doxorubicin versus topotecan

PURPOSE

To compare the efficacy and safety of pegylated liposomal doxorubicin (PLD) and topotecan in patients with epithelial ovarian carcinoma that recurred after or didn't respond to first-line, platinum-based chemotherapy.

PATIENTS AND METHODS

Patients with measurable and assessable disease were randomized to receive either PLD 50 mg/m(2) as a 1-hour infusion every 4 weeks or topotecan 1.5 mg/m(2)/d for 5 consecutive days every 3 weeks. Patients were stratified prospectively for platinum sensitivity and for the presence or absence of bulky disease.

RESULTS

A total of 474 patients were treated (239 PLD and 235 topotecan). They comprised the intent-to-treat population. The overall progression-free survival rates were similar between the two arms (P =.095). The overall response rates for PLD and topotecan were 19.7% and 17.0%, respectively (P =.390). Median overall survival times were 60 weeks for PLD and 56.7 weeks for topotecan. Data analyzed in platinum-sensitive patients demonstrated a statistically significant benefit from PLD for progression-free survival (P =.037), with medians of 28.9 for PLD versus 23.3 weeks for topotecan. For overall survival, PLD was significantly superior to topotecan (P =.008), with a median of 108 weeks versus 71.1 weeks. The platinum-refractory subgroup demonstrated a nonstatistically significant survival trend in favor of topotecan (P =.455). Severe hematologic toxicity was more common with topotecan and was more likely to be associated with dosage modification, or growth factor or blood product utilization.

CONCLUSION

The comparable efficacy, favorable safety profile, and convenient dosing support the role of PLD as a valuable treatment option in this patient population.

Intraperitoneal cisplatin plus intravenous cyclophosphamide versus intravenous cisplatin plus intravenous cyclophosphamide for stage III ovarian cancer

BACKGROUND

Intravenous platinum-based chemotherapy is the standard primary therapy for advanced ovarian cancer. We conducted a phase 3 trial to compare the effects of intraperitoneal and intravenous cisplatin on the survival of women with previously untreated, stage III, epithelial ovarian cancer.

METHODS

The patients underwent an initial exploratory laparotomy and resection of all tumor masses larger than 2 cm. Within four weeks after surgery, six courses of intravenous cyclophosphamide (600 mg per square meter of body-surface area per course) plus either intraperitoneal cisplatin (100 mg per square meter) or intravenous cisplatin (100 mg per square meter) were administered at three-week intervals.

RESULTS

Of 654 randomized patients, 546 were eligible for the study. The estimated median survival was significantly longer in the group receiving intraperitoneal cisplatin (49 months; 95 percent confidence interval, 42 to 56) than in the group receiving intravenous cisplatin (41 months; 95 percent confidence interval, 34 to 47). The risk of death was lower in the intraperitoneal group than in the intravenous group (hazard ratio, 0.76; 95 percent confidence interval, 0.61 to 0.96; P = 0.02). Moderate-to-severe tinnitus, clinical hearing loss, and neuromuscular toxic effects were significantly more frequent in the intravenous group.

CONCLUSIONS

As compared with intravenous cisplatin, intraperitoneal cisplatin significantly improves survival and has significantly fewer toxic effects in patients with stage III ovarian cancer and residual tumor masses of 2 cm or less.

Angiostatin induces and sustains dormancy of human primary tumors in mice

There is now considerable direct evidence that tumor growth is angiogenesis-dependent. The most compelling evidence is based on the discovery of angiostatin, an angiogenesis inhibitor that selectively instructs endothelium to become refractory to angiogenic stimuli. Angiostatin, which specifically inhibits endothelial proliferation, induced dormancy of metastases defined by a balance of apoptosis and proliferation. We now show that systemic administration of human angiostatin potently inhibits the growth of three human and three murine primary carcinomas in mice. An almost complete inhibition of tumor growth was observed without detectable toxicity or resistance. The human carcinomas regressed to microscopic dormant foci in which tumor cell proliferation was balanced by apoptosis in the presence of blocked angiogenesis. This regression of primary tumors without toxicity has not been previously described. This is also the first demonstration of dormancy therapy, a novel anticancer strategy in which malignant tumors are regressed by prolonged blockade of angiogenesis.

Arterial thromboembolic events in patients with metastatic carcinoma treated with chemotherapy and bevacizumab

BACKGROUND

Although combination treatment with bevacizumab (humanized monoclonal antibody against vascular endothelial growth factor) and chemotherapy improves survival of patients with various metastatic carcinomas, an increased risk of arterial thromboembolic events has been observed in some trials. We characterized this risk by performing post hoc analyses of randomized controlled trials that evaluated combination treatment with bevacizumab and chemotherapy versus chemotherapy alone. Low-dose aspirin was permitted in these trials, and its safety was also analyzed.

METHODS

Data were pooled from five randomized controlled trials that included a total of 1745 patients with metastatic colorectal, breast, or non-small-cell lung carcinoma. The risk of an arterial or venous thromboembolic event was assessed by simple incidence rates, rates per 100 person-years, and/or hazard ratios (HRs). The association between patient characteristics and risk of an arterial thromboembolic event was investigated primarily by Cox proportional hazards regression. The relationship between low-dose aspirin and bleeding was explored by incidence rates and rates per 100 person-years.

RESULTS

Combined treatment with bevacizumab and chemotherapy, compared with chemotherapy alone, was associated with increased risk for an arterial thromboembolic event (HR = 2.0, 95% confidence interval [CI] = 1.05 to 3.75; P = .031) but not for a venous thromboembolic event (HR = 0.89, 95% CI = 0.66 to 1.20; P = .44). The absolute rate of developing an arterial thromboembolism was 5.5 events per 100 person-years for those receiving combination therapy and 3.1 events per 100 person-years for those receiving chemotherapy alone (ratio = 1.8, 95% CI = 0.94 to 3.33; P = .076). Development of an arterial thromboembolic event was associated with a prior arterial thromboembolic event (P<.001) or age of 65 years or older (P = .01). Baseline or on-study aspirin use was associated with modest increases in grade 3 and 4 bleeding events in both treatment groups, from 3.6% to 4.7% for bevacizumab-treated patients and from 1.7% to 2.2% for control subjects.

CONCLUSIONS

Combination treatment with bevacizumab and chemotherapy, compared with chemotherapy alone, was associated with an increased risk of arterial thromboembolism but not venous thromboembolism.

Histomorphology and grading of regression in gastric carcinoma treated with neoadjuvant chemotherapy

BACKGROUND

Neoadjuvant chemotherapy has shown some success in the treatment of gastric carcinoma, but objective parameters for measuring its effects are lacking. The authors performed the current study to determine which histomorphologic features are correlated with patient prognosis after chemotherapy.

METHODS

Thirty-six patients with gastric carcinoma were treated with a combination of etoposide, doxorubicin, and cisplatin. The entire tumor beds of the specimens were evaluated histologically and compared with specimens treated with surgery alone. Thirty-four patients were available for survival analysis (follow-up period, 60-130 months).

RESULTS

None of the 36 patients had complete tumor regression, 4 patients had marked regression (less than 10% viable tumor), 9 patients had regression to 10-50% remaining viable tumor, and 23 patients had more than 50% viable tumor remaining. Currently, 9 patients are still alive (5-year survival rate, 27%). Tumor regression was found to be correlated significantly with survival (P = 0.01), but tumor size (P = 0.002) and lymphatic vessel invasion (P = 0.003) were better predictors of prognosis.

CONCLUSIONS

Histologic tumor regression grade is an objective measure of the effects of neoadjuvant chemotherapy in patients with gastric carcinoma, but its accuracy may be improved by adding additional staging variables such as tumor size and lymphatic vessel involvement. Cancer 2003;98:1521-30.

Pembrolizumab for Persistent, Recurrent, or Metastatic Cervical Cancer

BACKGROUND

Pembrolizumab has efficacy in programmed death ligand 1 (PD-L1)-positive metastatic or unresectable cervical cancer that has progressed during chemotherapy. We assessed the relative benefit of adding pembrolizumab to chemotherapy with or without bevacizumab.

METHODS

In a double-blind, phase 3 trial, we randomly assigned patients with persistent, recurrent, or metastatic cervical cancer in a 1:1 ratio to receive pembrolizumab (200 mg) or placebo every 3 weeks for up to 35 cycles plus platinum-based chemotherapy and, per investigator discretion, bevacizumab. The dual primary end points were progression-free survival and overall survival, each tested sequentially in patients with a PD-L1 combined positive score of 1 or more, in the intention-to-treat population, and in patients with a PD-L1 combined positive score of 10 or more. The combined positive score is defined as the number of PD-L1-staining cells divided by the total number of viable tumor cells, multiplied by 100. All results are from the protocol-specified first interim analysis.

RESULTS

In 548 patients with a PD-L1 combined positive score of 1 or more, median progression-free survival was 10.4 months in the pembrolizumab group and 8.2 months in the placebo group (hazard ratio for disease progression or death, 0.62; 95% confidence interval [CI], 0.50 to 0.77; P<0.001). In 617 patients in the intention-to-treat population, progression-free survival was 10.4 months and 8.2 months, respectively (hazard ratio, 0.65; 95% CI, 0.53 to 0.79; P<0.001). In 317 patients with a PD-L1 combined positive score of 10 or more, progression-free survival was 10.4 months and 8.1 months, respectively (hazard ratio, 0.58; 95% CI, 0.44 to 0.77; P<0.001). Overall survival at 24 months was 53.0% in the pembrolizumab group and 41.7% in the placebo group (hazard ratio for death, 0.64; 95% CI, 0.50 to 0.81; P<0.001), 50.4% and 40.4% (hazard ratio, 0.67; 95% CI, 0.54 to 0.84; P<0.001), and 54.4% and 44.6% (hazard ratio, 0.61; 95% CI, 0.44 to 0.84; P = 0.001), respectively. The most common grade 3 to 5 adverse events were anemia (30.3% in the pembrolizumab group and 26.9% in the placebo group) and neutropenia (12.4% and 9.7%, respectively).

CONCLUSIONS

Progression-free and overall survival were significantly longer with pembrolizumab than with placebo among patients with persistent, recurrent, or metastatic cervical cancer who were also receiving chemotherapy with or without bevacizumab. (Funded by Merck Sharp and Dohme; KEYNOTE-826 ClinicalTrials.gov number, NCT03635567.).

Treatment of neuroendocrine carcinomas with combined etoposide and cisplatin. Evidence of major therapeutic activity in the anaplastic variants of these neoplasms

Forty-five patients with metastatic neuroendocrine tumors were treated with a regimen of etoposide 130 mg/m2/d for 3 days plus cisplatin 45 mg/m2/d on days 2 and 3. Both drugs were given by continuous intravenous infusion. Among 27 patients with well-differentiated carcinoid tumors or islet cell carcinomas, only two partial objective tumor regressions were observed (7%). Among 18 patients prospectively classified as having anaplastic neuroendocrine carcinomas, however, there were nine partial regressions and three complete regressions, an overall regression rate of 67%. For anaplastic disease, the median duration of regression was 8 months (range to 21 months). Tumor response was unrelated to primary site, endocrine hyperfunction, or prior therapy experience. The median survival of all patients with anaplastic tumors was 19 months; this seemed favorable when considering the small experiences with these rare tumors reported in the literature. Toxicity, which was severe for most patients, consisted primarily of vomiting, leukopenia, thrombocytopenia, anemia, alopecia, and neuropathy. The anaplastic neuroendocrine tumor is strongly responsive to therapy with combined etoposide and cisplatin. Patients with undifferentiated carcinomas, originating in typical neuroendocrine tumor sites (small and large bowel, pancreas, and stomach) or of unknown origin, who have consistent histologic findings by light microscopy should be evaluated for this possibility with appropriate immune staining or electron microscopy.

Phase III randomized trial of docetaxel-carboplatin versus paclitaxel-carboplatin as first-line chemotherapy for ovarian carcinoma

BACKGROUND

Chemotherapy with a platinum agent and a taxane (paclitaxel) is considered the standard of care for treatment of ovarian carcinoma. We compared the combination of docetaxel-carboplatin with the combination of paclitaxel-carboplatin as first-line chemotherapy for stage Ic-IV epithelial ovarian or primary peritoneal cancer.

METHODS

We randomly assigned 1077 patients to receive docetaxel at 75 mg/m2 of body surface area (1-hour intravenous infusion) or paclitaxel at 175 mg/m2 (3-hour intravenous infusion). Both treatments then were followed by carboplatin to an area under the plasma concentration-time curve of 5. The treatments were repeated every 3 weeks for six cycles; in responding patients, an additional three cycles of single-agent carboplatin was permitted. Survival curves were calculated by the Kaplan-Meier method, and hazard ratios were estimated with the Cox proportional hazards model. All statistical tests were two-sided.

RESULTS

After a median follow-up of 23 months, both groups had similar progression-free survival (medians of 15.0 months for docetaxel-carboplatin and 14.8 months for paclitaxel-carboplatin; hazard ratio [HR] docetaxel-paclitaxel = 0.97, 95% confidence interval [CI] = 0.83 to 1.13; P = .707), overall survival rates at 2 years (64.2% and 68.9%, respectively; HR = 1.13, 95% CI = 0.92 to 1.39; P = .238), and objective tumor (58.7% and 59.5%, respectively; difference between docetaxel and paclitaxel = -0.8%, 95% CI = -8.6% to 7.1%; P = .868) and CA-125 (75.8% and 76.8%, respectively; difference docetaxel-paclitaxel = -1.0%, 95% CI = -7.2% to 5.1%; P = .794) response rates. However, docetaxel-carboplatin was associated with substantially less overall and grade 2 or higher neurotoxicity than paclitaxel-carboplatin (grade > or =2 neurosensory toxicity in 11% versus 30%, difference = 19%, 95% CI = 15% to 24%; P<.001; grade > or =2 neuromotor toxicity in 3% versus 7%, difference = 4%, 95% CI = 1% to 7%; P<.001). Treatment with docetaxel-carboplatin was associated with statistically significantly more grade 3-4 neutropenia (94% versus 84%, difference = 11%, 95% CI = 7% to 14%; P<.001) and neutropenic complications than treatment with paclitaxel-carboplatin, although myelosuppression did not influence dose delivery or patient safety. Global quality of life was similar in both arms, but substantive differences in many symptom scores favored docetaxel.

CONCLUSIONS

Docetaxel-carboplatin appears to be similar to paclitaxel-carboplatin in terms of progression-free survival and response, although longer follow-up is required for a definitive statement on survival. Thus, docetaxel-carboplatin represents an alternative first-line chemotherapy regimen for patients with newly diagnosed ovarian cancer.

Methotrexate: distribution in cerebrospinal fluid after intravenous, ventricular and lumbar injections

The kinetics and distribution of methotrexate in intraventricular and intrathecal cerebrospinal-fluid spaces were studied in patients with meningeal leukemia and meningeal carcinomatosis after drug administration by intravenous infusion, indwelling intraventricular subcutaneous reservoir (Ommaya), or standard lumbar puncture. Negligible ventricular concentrations followed a single intravenous dose. During an intravenous infusion (500 mg per square meter for 24 hours) the ventricular cerebrospinal-fluid concentration rose to 6 times 10-minus 7 M. Methotrexate administered by Ommaya reservoir, at a dose of 6.25 mg per square meter, rapidly distributed in the subarachnoid space; the peak ventricular concentration of 2 times 10-minus 4 M declined exponentially over 48 hours. Lumbar cerebrospinal-fluid concentration reached a maximum of 5 times 10-minus 5 M four hours after injection and then fell exponentially. Administration by lumbar puncture occasionally produced epidural and subdural leakage; even with successful lumbar puncture, ventricular methotrexate concentration varied considerably from patient to patient despite similar doses. Administration by Ommaya reservoir more reliably produced adequate cerebrospinal fluid distribution than administration by lumbar puncture.

Activation of latent TGF-beta by thrombospondin-1: mechanisms and physiology

Regulation of the activation of latent TGF-beta is essential for health as too much or too little TGF-beta activity can have serious, deleterious consequences. The processes that control conversion of the precursor to the biologically active form of TGF-beta in vivo are not well characterized. We have identified a mechanism for the activation of latent TGF-beta that involves binding of the secreted and extracellular matrix protein, thrombospondin-1 (TSP-1), to the latent precursor. Specific sequences in TSP-1 and in the precursor portion (the latency associate peptide-LAP) have been determined to be essential for activation of latent TGF-beta by TSP-1. It is thought that binding of TSP-1 to the latent complex induces a conformational rearrangement of the LAP in such a manner as to prevent the LAP from conferring latency on the mature domain of TGF-beta. A TSP-dependent mechanism of activation may be locally important during wound healing and in post-natal development of epithelial structures. The possible involvement of TSP-1 in TGF-beta activation during several disease processes is also discussed.

CTLA-4 blockade increases IFNgamma-producing CD4+ICOShi cells to shift the ratio of effector to regulatory T cells in cancer patients

Significant anti-tumor responses have been reported in a small subset of cancer patients treated with the immunotherapeutic agent anti-CTLA-4 antibody. All clinical trials to date, comprising over 3,000 patients, have been conducted in the metastatic disease setting, which allows for correlation of drug administration with clinical outcome but has limited analyses of intermediate biomarkers to indicate whether the drug has impacted human immune responses within the tumor microenvironment. We conducted a pre-surgical clinical trial in six patients with localized bladder cancer, which allowed for correlation of drug administration with biomarkers in both blood and tumor tissues but did not permit correlation with clinical outcome. We found that CD4 T cells from peripheral blood and tumor tissues of all treated patients had markedly increased expression of inducible costimulator (ICOS). These CD4(+)ICOS(hi) T cells produced IFN-gamma (IFNgamma) and could recognize the tumor antigen NY-ESO-1. Increase in CD4(+)ICOS(hi) cells led to an increase in the ratio of effector to regulatory T cells. To our knowledge, these are the first immunologic changes reported in both tumor tissues and peripheral blood as a result of treatment with anti-CTLA-4 antibody, and they may be used to guide dosing and scheduling of this agent to improve clinical responses.

Multicenter phase II and translational study of cetuximab in metastatic colorectal carcinoma refractory to irinotecan, oxaliplatin, and fluoropyrimidines

PURPOSE

This multicenter study evaluated the antitumor activity of cetuximab, an immunoglobulin G1 antibody directed at the epidermal growth factor receptor (EGFR), in metastatic colorectal carcinoma (CRC) refractory to irinotecan, oxaliplatin, and a fluoropyrimidine. It also evaluated the safety, pharmacokinetics, immunokinetics, and biologic determinants of activity.

PATIENTS AND METHODS

Patients with metastatic CRC, whose tumors demonstrated EGFR immunostaining and were refractory to irinotecan, oxaliplatin, and fluoropyrimidines, were treated with cetuximab at a loading dose of 400 mg/m2 followed by 250 mg/m2 weekly. An independent review committee (IRC) reviewed responses. Blood was collected for cetuximab pharmacokinetics and to detect antibodies to cetuximab. EGFR gene sequencing of the tyrosine kinase domain and gene copy number assessments were performed.

RESULTS

The response rates in 346 patients, as determined by the investigators and IRC, were 12.4% (95% CI, 9.1 to 16.4) and 11.6% (95% CI, 8.4 to 16.4). The median progression-free survival (PFS) and survival times were 1.4 months (95% CI, 1.4 to 2.1) and 6.6 months (95% CI, 5.6 to 7.6), respectively. An acneiform rash occurred in 82.9% of patients; grade 3 rash was observed in 4.9%. Response and survival related strongly to the severity of the rash. In contrast, clinical benefit did not relate to EGFR immunostaining. EGFR tyrosine kinase domain mutations were not identified, and EGFR gene copy number did not relate to response or PFS, but to survival (P = .03).

CONCLUSION

Cetuximab is active and well tolerated in metastatic CRC refractory to irinotecan, oxaliplatin, and fluoropyrimidines. The severity of rash was related to efficacy. Neither EGFR kinase domain mutations nor EGFR gene amplification appear to be essential for response to cetuximab in this setting.

A subpopulation of CD26+ cancer stem cells with metastatic capacity in human colorectal cancer

Recent evidence suggests that a subpopulation of cancer cells, cancer stem cells (CSCs), is responsible for tumor growth in colorectal cancer. However, the role of CSCs in colorectal cancer metastasis is unclear. Here, we identified a subpopulation of CD26(+) cells uniformly present in both the primary and metastatic tumors in colorectal cancer patients with liver metastasis. Furthermore, in patients without distant metastasis at the time of presentation, the presence of CD26(+) cells in their primary tumors predicted distant metastasis on follow-up. Isolated CD26(+) cells, but not CD26(-) cells, led to development of distant metastasis when injected into the mouse cecal wall. CD26(+) cells were also associated with enhanced invasiveness and chemoresistance. Our findings have uncovered a critical role of CSCs in metastatic progression of cancer. Furthermore, the ability to predict metastasis based on analysis of CSC subsets in the primary tumor may have important clinical implication as a selection criterion for adjuvant therapy.

Delocalized lipophilic cations selectively target the mitochondria of carcinoma cells

Traditional chemotherapies, aimed at DNA replication in rapidly dividing cells, have achieved only limited success in the treatment of carcinomas due largely to their lack of specificity for cells of tumorigenic origin. It is important, therefore, to investigate treatment strategies aimed at novel cellular targets that are sufficiently different between normal cells and cancer cells so as to provide a basis for selective tumor cell killing. Delocalized lipophilic cations (DLCs) are concentrated by cells and into mitochondria in response to negative inside transmembrane potentials. The higher plasma and/or mitochondrial membrane potentials of carcinoma cells compared to normal epithelial cells account for the selective accumulation of DLCs in carcinoma mitochondria. Since most DLCs are toxic to mitochondria at high concentrations, their selective accumulation in carcinoma mitochondria and consequent mitochondrial toxicity provide a basis for selective carcinoma cell killing. Several of these compounds have already displayed some degree of efficacy as chemotherapeutic agents in vitro and in vivo. The effectiveness of DLCs can also be enhanced by their use in photochemotherapy or combination drug therapy. Discovery of the biochemical differences that account for the higher membrane potentials in carcinoma cells is expected to lead to the design of new DLCs targeted specifically to those differences, resulting in even greater selectivity and efficacy for tumor cell killing.