Phase 1 clinical trials in 83 patients with pancreatic cancer: The M. D. Anderson Cancer Center experience

BACKGROUND

The outcomes of patients with pancreatic cancer treated on early phase clinical trials have not been systematically analyzed. The purpose of this study was to report the presenting characteristics and outcomes of patients with locally advanced or metastatic pancreatic cancer treated on phase 1 clinical trials at a single institution.

METHODS

The authors reviewed the records of consecutive patients with metastatic pancreatic cancer who were treated in the Phase I Clinical Trials Program at The University of Texas M. D. Anderson Cancer Center from November 2004 to March 2009. Data recorded and analyzed included survival, response, and disease characteristics.

RESULTS

Eighty-three patients were identified. The median age was 62 years (range, 39-81 years). Of 78 patients evaluable for response, 2 (3%) had a partial response (PR), and 10 (13%) had stable disease (SD) for ≥ 4 months. With a median follow-up for survivors of 3.7 months, the median survival from presentation in the phase 1 clinic was 5.0 months (95% confidence interval [CI], 3.3-6.2). The median overall survival from diagnosis was 22.1 months (95% CI, 17.9-26.5). The median time to treatment failure was 1.5 months (95% CI, 1.3-1.8). Independent factors associated with lower rates of PR/SD were liver metastases (P = .001) and performance status >0 (P = .01). Independent factors associated with shorter survival were liver metastases (P = .007), low calcium level (P = .015), and elevated CEA level (>6 ng/mL) (P = .005).

CONCLUSIONS

Our results suggest that phase 1 clinical trials offer a reasonable therapeutic approach for patients with advanced pancreatic cancer.

Molecularly targeted therapies for thyroid cancers

OBJECTIVE

To review the emerging evidence that therapies targeting key oncogenic and signaling kinases can be effective in treatment of advanced thyroid carcinomas.

METHODS

With use of PubMed and Google Scholar, a systematic review was performed of publications and scientific presentations summarizing pertinent clinical trials.

RESULTS

Studies of numerous inhibitors of BRAF, vascular endothelial growth factor receptor, and RET kinases indicate that patients with progressive or metastatic thyroid carcinoma can benefit from therapy with these novel agents. Severe toxic effects, however, are associated with these treatments, and caution is recommended in their use.

CONCLUSION

Further trials and identification of improved therapeutic targeting should lead to development of more effective treatments of thyroid carcinomas.

Tyrosine kinase inhibitors and the thyroid

Protein tyrosine kinase inhibitors (TKIs) have emerged as significant targets for novel cancer therapies. For patients with differentiated or medullary carcinomas unresponsive to conventional treatments, multiple novel therapies primarily targeting angiogenesis have entered clinical trials. Partial response rates up to 30% have been reported in single-agent studies, but prolonged disease stabilisation is more commonly seen. The most successful agents target the vascular endothelial growth factor receptors. Sorafenib and sunitinib have had promising preliminary results reported and are being used selectively for patients who do not qualify for clinical trials. Treatment for patients with metastatic or advanced thyroid carcinoma now emphasises clinical trial opportunities for novel agents with considerable promise. Adverse effects on thyroid function and thyroid hormone metabolism have also been seen with several TKIs, necessitating prospective thyroid function testing for all patients starting therapy.

Advances in chemotherapy of differentiated epithelial and medullary thyroid cancers

CONTEXT

Systemic chemotherapies for advanced or metastatic thyroid carcinomas have been of only limited effectiveness. For patients with differentiated or medullary carcinomas unresponsive to conventional treatments, novel therapies are needed to improve disease outcomes.

EVIDENCE ACQUISITION

The PubMed and Google Scholar search engines were used to identify publications and peer-reviewed meeting presentations addressing chemotherapy and targeted therapy for differentiated or medullary carcinoma.

EVIDENCE SYNTHESIS

Multiple novel therapies primarily targeting angiogenesis have entered clinical trials for metastatic thyroid carcinoma. Partial response rates up to 30% have been reported in single agent studies, but prolonged disease stabilization is more commonly seen. The most successful agents target the vascular endothelial growth factor receptors, with potential targets including the mutant kinases associated with papillary and medullary oncogenesis. Two drugs approved for other malignancies, sorafenib and sunitinib, have had promising preliminary results reported, and are being used selectively for patients who do not qualify for clinical trials. Randomized trials for several agents are underway that may lead to eventual drug approval for thyroid cancer.

CONCLUSION

Treatment for patients with metastatic or advanced thyroid carcinoma now emphasizes clinical trial opportunities for novel agents with considerable promise. Alternative options now exist for use of tyrosine kinase inhibitors that are well tolerated and may prove worthy of regulatory approval for this disease.

Rho GTPases in hepatocellular carcinoma

Rho GTPases are major regulators of signal transduction pathways and play key roles in processes including actin dynamics, cell cycle progression, cell survival and gene expression, whose deregulation may lead to tumorigenesis. A growing number of in vitro and in vivo studies using tumor-derived cell lines, primary tumors and animal cancer models strongly suggest that altered Rho GTPase signaling plays an important role in the initiation as well as in the progression of hepatocellular carcinoma (HCC), one of the deadliest human cancers in the world. These alterations can occur at the level of the GTPases themselves or of one of their regulators or effectors. The participation into the tumorigenic process can occur either through the over-expression of one of these components which presents an oncogenic activity as illustrated with RhoA and C or through the attenuation of the expression of a component presenting tumor suppressor activity as for Cdc42 or the RhoGAP, DLC-1. Consequently, these observations reflect the heterogeneity and the complexity of liver carcinogenesis. Recently, pharmacological approaches targeting Rho GTPase signaling have been used in HCC-derived models with relative success but remain to be validated in more physiologically relevant systems. Therefore, therapeutic approaches targeting Rho GTPase signaling may provide a novel alternative for anti-HCC therapy.