Adaptive therapy to circumvent drug resistance to tyrosine kinase inhibitors in cancer: is it clinically relevant?

INTRODUCTION: Cancer is highly adaptable and is constantly evolving against current targeted therapies such as tyrosine kinase inhibitors. Despite advances in recent decades, the emergence of drug resistance to tyrosine kinase inhibitors constantly hampers therapeutic efficacy of cancer treatment. Continuous therapy versus intermittent clinical regimen has been a debate in drug administration of cancer patients. An ecologically-inspired shift in cancer treatment known as 'adaptive therapy' intends to improve the drug administration of drugs to cancer patients that can delay emergence of drug resistance. AREAS COVERED: We discuss improved understanding of the concept of drug resistance, the basis of continuous therapy, intermittent clinical regimens, and adaptive therapy will be reviewed. In addition, we discuss how adaptive therapy provides guidance for future cancer treatment. EXPERT OPINION: The current understanding of drug resistance in cancer leads to poor prognosis and limited treatment options in patients. Fighting drug resistance mutants is constantly followed by new forms of resistance. In most reported cases, continuous therapy leads to drug resistance and an intermittent clinical regimen vaguely delays it. However, adaptive therapy, conceptually, exploits multiple parameters that can suppress the growth of drug resistance and provides safe treatment for cancer patients in the future.

Catastrophic cutaneous carcinomatosis in the non-organ transplant patient.

BACKGROUND: The increased frequency of nonmelanoma skin cancers (NMSCs) in organ transplant recipients has been termed "catastrophic cutaneous carcinomatosis" (CCC). We have treated a cohort of immunocompetent patients with an increased number of NMSCs that meets the definition of CCC whom we have termed "catastrophic cutaneous carcinomatosis-immunocompetent" (CCC-IC). OBJECTIVE: We sought to further understand the epidemiologic characteristics of this subset of immunocompetent patients with a high burden of NMSCs. METHODS: Our pathology database was searched over a 4-year experience of a Mohs surgeon to identify patients with greater than 10 basal cell carcinomas (BCCs) and/or squamous cell carcinomas (SCCs) in a 12-month period who had no underlying systemic cause of immunosuppression or genetic predisposition to form NMSCs. Information regarding the 13 patients who met inclusion criteria was collected by questionnaire and analyzed. RESULTS: There was no statistically significant difference in the constitutional variables of this patient population. Patients with CCC-IC had a SCC:BCC ratio of 2.5:1, similar to what is seen in organ transplant recipients where the SCC:BCC ratio is 2:1 with SCC predominance. There was a statistically significant increase in the number of SCCs in patients with CCC-IC (8.77/patient) as compared with control patients (2.27/patient). Most strikingly, a 13.8-fold higher incidence of malignant melanoma in the CCC-IC group was found as compared with the general population. LIMITATIONS: Limitations to this study include a small sample size and recall bias. CONCLUSION: Our data suggest that patients with CCC-IC have skin cancer profiles of SCC and BCC similar to organ transplant recipients and have a markedly higher incidence of malignant melanoma than the general population. These patients require strict monitoring and combination therapeutic approaches toward management of cutaneous carcinomas.

Osteoinvasive subungual melanoma: a case and review.

Subungual melanoma is a relatively rare variant of melanoma, accounting for 0.7-3.5% of all melanoma cases in the Caucasian population. Curiously, it occurs in 8-33% of cases in black, Asian, Native American and Hispanic populations, which generally face a substantially lower risk of melanoma. Herein the authors report the case of a 69-year-old Hispanic female with a subungual melanoma of the acral lentiginous type that directly invaded the periosteum, cortex and medulla of the distal phalanx. In addition, we review published reports of acral lentiginous melanoma with osseous invasion and discuss the evidence, on a molecular level, for this entity's aggressive pattern of invasion. The review of cases is limited to those found through the PubMed search engine.