Preliminary characterization of oral lesions associated with inhibitors of mammalian target of rapamycin in cancer patients

Prevalence and clinical characteristics of oral lesions in heart transplant patients induced by sirolimus and everolimus: a systematic review and meta-analysis on a global scale

OBJECTIVE

Sirolimus (SRL) and everolimus (EVL) are increasingly included in immunosuppressive protocols after heart transplantation. They present some side effects, including the appearance of painful lesions in the oral cavity. Therefore, this systematic review aimed to verify the global prevalence and clinical characteristics of oral lesions induced by SRL and EVL in heart transplant patients.

STUDY DESIGN

A systematic review was performed using 5 main electronic databases (Medline/PubMed, SCOPUS, EMBASE, Web of Science, and LILACS), in addition to the gray literature. Studies were independently assessed by 2 reviewers based on established eligibility criteria. The risk of bias was assessed using the Joanna Briggs Institute appraisal tools, and the certainty of evidence was evaluated through GRADE assessment.

RESULTS

Seventeen studies (860 patients) were included in the qualitative analysis. Of these, 11 studies were pooled in a meta-analysis of prevalence. The worldwide prevalence of oral lesions induced by SRL and EVL in heart transplant patients was 10.0%, and most lesions were described as ulcers >1.0 cm, related to significant pain.

CONCLUSIONS

Oral lesions induced by SRL and/or EVL, although not very prevalent, have a relevant impact on patient's lives and the continuity of treatment.

A New Hypothesis Describing the Pathogenesis of Oral Mucosal Injury Associated with the Mammalian Target of Rapamycin (mTOR) Inhibitors

It has been 24 years since rapamycin (sirolimus) was approved to mitigate solid organ transplant rejection and 16 years since mTOR (mammalian/mechanistic target of rapamycin) inhibitors reached patients as a cancer therapy. While the clinical benefits of mTOR inhibitors (mTORi) are robust, so too are their toxicities. Among the most common issues is the development of ulcers of the oral mucosa (mTOR-inhibitor associated stomatitis; mIAS). These lesions are distinct from those of other anti-cancer agents, occur with regularity, and impact patient outcomes. mIAS' pathogenesis has been the subject of speculation, and its similar presentation to recurrent aphthous stomatitis (RAS) has led to the hypothesis that it might serve as a surrogate to better understand RAS. Based on a review of the literature, the current manuscript provides a hypothesis regarding the mechanisms by which mTORis uniquely initiate mucosal injury and an explanation for the observation that steroids (also an immunosuppressive) are effective in its treatment through a non-immunologic mechanism. Unexplained unique features of mIAS are discussed in this review in the context of future investigation.

The broadening scope of oral mucositis and oral ulcerative mucosal toxicities of anticancer therapies

Oral mucositis (OM) is a common, highly symptomatic complication of cancer therapy that affects patients' function, quality of life, and ability to tolerate treatment. In certain patients with cancer, OM is associated with increased mortality. Research on the management of OM is ongoing. Oral mucosal toxicities are also reported in targeted and immune checkpoint inhibitor therapies. The objective of this article is to present current knowledge about the epidemiology, pathogenesis, assessment, risk prediction, and current and developing intervention strategies for OM and other ulcerative mucosal toxicities caused by both conventional and evolving forms of cancer therapy.

Berunda Polypeptides Carrying Rapalogues Inhibit Tumor mTORC1 Better than Oral Everolimus

Rapalogues are a unique class of drugs with both cytostatic and immunosuppressive properties. Two founding members, rapamycin (Rapa) and its chemical derivative everolimus (Eve), are extremely potent, but their clinical use presents multiple challenges. Being water-insoluble, administration is restricted to the oral route, which results in a low bioavailability of <10%. Human studies of rapalogues are reported to yield a high blood to plasma ratio and poor correlation between blood concentration and dose. Moreover, treatment results in dose-limiting toxicities such as stomatitis and pneumonitis, which often leads to discontinuation of therapy. We previously reported an elastin-like polypeptide decorated with two-headed FKBP rapalogue-binding domains. Called "FAF", this biomacromolecular drug-carrier solubilizes, retargets, and releases rapalogues within disease sites. FAF-rapalogue formulations are free of cosolvents or surfactants, which promotes their parenteral administration. In this study, subcutaneously given FAF-Rapa significantly suppressed tumor growth in a mouse model of hormone receptor positive (HR+) breast cancer, compared to an oral formulation of Eve (Affinitor). Additionally, mTOR, the pharmacological target of rapalogues, was inhibited to a greater extent in tumors of FAF-Rapa and FAF-Eve groups compared to mice that received oral Eve. No signaling suppression was detected in the liver and spleen, which were evaluated to represent off-target organs exposed to the circulating formulation.

Mechanistic basis for PI3K inhibitor antitumor activity and adverse reactions in advanced breast cancer

PURPOSE

The phosphatidylinositol 3-kinase (PI3K) pathway is involved in several physiological processes, including glucose metabolism, cell proliferation, and cell growth. Hyperactivation of this signaling pathway has been associated with tumorigenesis and resistance to treatment in various cancer types. Mutations that activate PIK3CA, encoding the PI3K isoform p110α, are common in breast cancer, particularly in the hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) subtype. A number of PI3K inhibitors have been developed and evaluated for potential clinical use in combinations targeting multiple signaling pathways in cancer. The purpose of this review is to provide an overview of PI3K inhibitor mechanisms of action for antitumor activity and adverse events in advanced breast cancer (ABC).

METHODS

Published results from phase 3 trials evaluating the efficacy and safety of PI3K inhibitors in patients with ABC and relevant literature were reviewed.

RESULTS

Although PI3K inhibitors have been shown to prolong progression-free survival (PFS), the therapeutic index is often unfavorable. Adverse events, such as hyperglycemia, rash, and diarrhea are frequently observed in these patients. In particular, hyperglycemia is intrinsically linked to the inhibition of PI3Kα, a key mediator of insulin signaling. Off-target effects, including mood disorders and liver toxicity, have also been associated with some PI3K inhibitors.

CONCLUSION

Recent clinical trial results show that specifically targeting PI3Kα can improve PFS and clinical benefit. Broad inhibition of class I PI3Ks appears to result in an unfavorable safety profile due to off-target effects, limiting the clinical utility of the early PI3K inhibitors.

Sirolimus and mTOR Inhibitors: A Review of Side Effects and Specific Management in Solid Organ Transplantation

Inhibitors of mechanistic target of rapamycin (mTOR inhibitors) are used as antiproliferative immunosuppressive drugs and have many clinical applications in various drug combinations. Experience in transplantation studies has been gained regarding the side effect profile of these drugs and the potential benefits and limitations compared with other immunosuppressive agents. This article reviews the adverse effects of mTOR inhibitors in solid organ transplantation, with special attention given to mechanisms hypothesized to cause adverse events and their management strategies.

Stomatitis And Everolimus: A Review Of Current Literature On 8,201 Patients

Background

Oral toxicities, such as mucositis and stomatitis, are some of the most significant and unavoidable side effects associated with anticancer therapies. In past decades, research has focused on newer targeted agents with the aim of decreasing the rates of side effects on healthy cells. Unfortunately, even targeted anticancer therapies show significant rates of toxicity on healthy tissue. mTOR inhibitors display some adverse events, such as hyperglycemia, hyperlipidemia, hypophosphatemia, hematologic toxicities, and mucocutaneous eruption, but the most important are still stomatitis and skin rash, which are often dose-limiting side effects.

Aim

This review was performed to answer the question “What is the incidence of stomatitis in patients treated with everolimus?”

Methods

We conducted a systematic search on the PubMed and Medline online databases using a combination of MESH terms and free text: “everolimus” (MESH) AND “side effects” OR “toxicities” OR “adverse events”. Only studies fulfilling the following inclusion criteria were considered eligible for inclusion in this study: performed on human subjects, reporting on the use of everolimus (even if in combination with other drugs or ionizing radiation), written in the English language, and reporting the incidence of side effects.

Results

The analysis of literature revealed that the overall incidence of stomatitis after treatment with everolimus was 42.6% (3,493) and that of stomatitis grade G1/2 84.02% (2,935), while G3/4 was 15.97% (558).

Conclusion

Results of the analysis showed that the incidence of stomatitis of grade 1 or 2 is higher than grade 3 or 4. However, it must be taken into account that it is not possible to say if side effects are entirely due to everolimus therapy or combinations with other drugs.

A review and guide to drug-associated oral adverse effects-Oral mucosal and lichenoid reactions. Part 2

Dental practitioners and other health professionals commonly encounter and manage adverse medicine effects that manifest in the orofacial region. Numerous medicines are associated with a variety of oral adverse effects. However, due to lack of awareness and training, these side effects are not always associated with medicine use and are underreported to pharmacovigilance agencies by dentists and other health professionals. This article aims to inform health professionals about the various oral adverse effects that can occur and the most commonly implicated drugs to improve the management, recognition and reporting of adverse drug effects. This article follows on from Part 1; however, the focus here is on lichenoid reactions and oral mucosal disorders including oral aphthous-like ulceration, mucositis and bullous disorders such as drug-induced pemphigus, pemphigoid, Stevens-Johnson syndrome and toxic epidermal necrolysis.

Mucosal Injury during Anti-Cancer Treatment: From Pathobiology to Bedside

Mucositis is one of the most common debilitating side effects related to chemotherapy (CT), radiation therapy (RT), targeted agents and immunotherapy. It is a complex process potentially involving any portion of the gastrointestinal tract and injuring the mucosa, leading to inflammatory or ulcerative lesions. Mechanisms and clinical presentation can differ according both to the anatomic site involved (oral or gastrointestinal) and the treatment received. Understanding the pathophysiology and management of mucosal injury as a secondary effect of anti-cancer treatment is an important area of clinical research. Prophylaxis, early diagnosis, and adequate management of complications are essential to increase therapeutic success and, thus, improve the survival outcomes of cancer patients. This review focuses on the pathobiology and management guidelines for mucositis, a secondary effect of old and new anti-cancer treatments, highlighting recent advances in prevention and discussing future research options.

A single-arm, phase 2 study of steroid-containing mouthwash for the prevention of everolimus-associated stomatitis in multiple tumor types

BACKGROUND

Everolimus is a mammalian target of rapamycin inhibitor used in the treatment of multiple tumor types, and its most common toxicity, stomatitis, can affect patient quality of life. Recent studies in breast cancer have supported the efficacy of steroid mouthwash for the prevention of everolimus-associated stomatitis. However, a few studies have been reported to date, and none have examined this effect in other tumor types.

METHODS

This single-arm phase 2 study was designed to evaluate the efficacy of steroid-containing mouthwash for the prevention of stomatitis in patients with multiple tumor types receiving everolimus. The primary outcome was incidence of grade ≥ 2 stomatitis at 8 weeks of everolimus with steroid-containing mouthwash prophylaxis. We also assessed the stability of steroid-containing mouthwash components.

RESULTS

Twenty-nine patients were evaluated, of which 76% had breast cancer and 24% had neuroendocrine tumors originating in the lung, gastrointestinal tract, pancreas, or of unknown primary origin. Grade ≥ 2 stomatitis incidence at 8 weeks was 28.1% (90% CI 16.2-46.1); the higher confidence limit exceeded the prespecified threshold of 30%. No patients developed grade ≥ 3 stomatitis. Most stomatitis occurred behind the oral cavity, with no lesions observed on the lips or floor of the mouth.

CONCLUSIONS

Our findings did not support a prophylactic effect of steroid-containing mouthwash on everolimus-associated stomatitis. Given the needs of prevention of everolimus-associated stomatitis in various tumor types, further studies in a larger population using a randomized controlled trial design are, therefore, required to confirm the efficacy of steroid-containing mouthwash.

Evaluation of Miracle Mouthwash plus Hydrocortisone Versus Prednisolone Mouth Rinses as Prophylaxis for Everolimus-Associated Stomatitis: A Randomized Phase II Study

BACKGROUND

Mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis (mIAS) is a frequent adverse event (AE) associated with mTOR inhibitor therapy and can impact treatment adherence. The objectives are to evaluate two steroid-based mouthrinses for preventing/ameliorating mIAS in patients with metastatic breast cancer (MBC) treated with everolimus.

MATERIALS AND METHODS

This prospective, randomized phase II study enrolled 100 postmenopausal patients with hormone receptor-positive MBC within the US Oncology Network who were initiating therapy with an aromatase inhibitor + everolimus (AIE; 10 mg/day). Patients were randomized to prophylactic therapy with one of two oral rinses (Arm 1: Miracle Mouthwash [MMW] 480 mL recipe: 320 mL oral Benadryl [diphenhydramine; Johnson & Johnson, New Brunswick, NJ, USA], 2 g tetracycline, 80 mg hydrocortisone, 40 mL nystatin suspension, water; or Arm 2: prednisolone [P] 15 mg/5 mL oral solution, 1.8% alcohol). Patients were instructed to swish/expectorate 10 mL of the assigned rinse for 1-2 minutes four times daily starting with day 1 of AIE treatment, for the first 12 weeks.

RESULTS

A total of 100 patients received treatment (49 MMW; 51 P). The incidence of stomatitis/oral AEs during the first 12 weeks was 35% (n = 17/49) and 37% (19/51) in the MMW and P arms, respectively. The incidence of grade 2 oral AEs was 14% (7/49) and 12% (6/51) with MMW or P, respectively. There were two grade 3 oral AEs (MMW arm) and no grade 4 events. There was one everolimus dose reduction (MMW) and six dose delays (four MMW, two P) and one dose reduction + delay (MMW) during the first 12 weeks of treatment. No patients stopped steroid mouthwash therapy because of rinse-related toxicity.

CONCLUSION

Prophylactic use of steroid-containing oral rinses can prevent/ameliorate mIAS in patients with MBC treated with AIE. MMW + hydrocortisone is an affordable option, as is dexamethasone oral rinse.

IMPLICATIONS FOR PRACTICE

This prospective phase-II study showed that two steroid-containing mouthrinses substantially reduced incidences of all-grade and grade ≥2 stomatitis and related oral adverse events (AEs), and the number of everolimus dose-delays and/or dose-reduction in metastatic breast cancer (MBC) patients receiving everolimus treatment plus an aromatase inhibitor. Both oral rinses were well tolerated and demonstrated similar efficacy. Prophylactic use of steroid mouth rinse provides a cost-effective option that substantially decreases the incidence and severity of mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis and related oral AEs as well as the need for dose modification in MBC patients undergoing treatment with an mTOR inhibitor.

A Review of Clinical Radioprotection and Chemoprotection for Oral Mucositis

The first tenet of medicine, "primum non nocere" or "first, do no harm", is not always compatible with oncological interventions e.g., chemotherapy, targeted therapy and radiation, since they commonly result in significant toxicities. One of the more frequent and serious treatment-induced toxicities is mucositis and particularly oral mucositis (OM) described as inflammation, atrophy and breakdown of the mucosa or lining of the oral cavity. The sequelae of oral mucositis (OM), which include pain, odynodysphagia, dysgeusia, decreased oral intake and systemic infection, frequently require treatment delays, interruptions and discontinuations that not only negatively impact quality of life but also tumor control and survivorship. One potential strategy to reduce or prevent the development of mucositis, for which no effective therapies exist only best supportive empirical care measures, is the administration of agents referred to as radioprotectors and/or chemoprotectors, which are intended to differentially protect normal but not malignant tissue from cytotoxicity. This limited-scope review briefly summarizes the incidence, pathogenesis, symptoms and impact on patients of OM as well as the background and mechanisms of four clinical stage radioprotectors/chemoprotectors, amifostine, palifermin, GC4419 and RRx-001, with the proven or theoretical potential to minimize the development of mucositis particularly in the treatment of head and neck cancers.

Current Trends in Management of Oral Mucositis in Cancer Treatment

Oral Mucositis (OM) is among the most common and dreaded toxicities of cancer therapy. It occurs in almost all patients who receive radiation therapy in which areas of oral and oropharyngeal mucosa are included in the treatment field. With the advent of chemotherapy in 1940 and its extended clinical legacy, it is only within the past two decade or so that mucositis’ complex pathobiology has become fully appreciated. There are still many unanswered questions about the risk factors for developing OM, but historically, risk factors have been attributed to both therapy and patient m characteristics. One thing that has been consistent from the initial descriptions of its clinical manifestations has been the frustration on the part of clinicians and patients with the scarcity of therapeutic options to prevent or treat the condition, or effectively ameliorate the symptoms. Clinicians, researchers and those involved in oral and periodontal medicine should join hand in hand in persuit of understanding and developing treatment strategies for treatment of inflammatory conditions like OM in oncology. This will lead to development of effective treatments and reducing the burden of OM and other inflammatory conditions in oncology.

New Frontiers in the Pathobiology and Treatment of Cancer Regimen-Related Mucosal Injury

Mucositis is a common complication of chemotherapy, radiotherapy and targeted agents. It often affects compliance to anticancer therapies as it frequently causes schedule delays, interruptions or discontinuations of treatment. Moreover, the economic impact related to the management of mucositis is topical and several estimations of additional hospital costs due to this clinical condition have been recently reported. The ability to determine risk factors for mucositis, to early detect its onset, to assess correctly the degree of this toxicity and to plan its multidisciplinary management are all key elements to guarantee the quality of life of patients and to avoid useless dose reduction or interruption of treatment. The pathogenesis of mucositis is multifactorial and it is classily subdivided into oral and gastrointestinal mucositis according to its anatomic presentation. Treatment and patients’ related factors might help in predicting the frequency and the potential degree of symptoms onset. Here we discuss about clinical presentation and pathogenesis of mucositis in relation to different kinds of treatments. Moreover, we focus on therapeutic and prevention strategies, describing past and present management according to international guidelines and the most promising new data about agents potentially able to further improve the treatment of mucositis in the next future.

Oral mucosal changes induced by anticancer targeted therapies and immune checkpoint inhibitors

Development of biological targeted therapies and immune checkpoint inhibitors has redefined the treatment for many cancers; however, the increasing use of new protocols has led to physicians observing a new spectrum of toxicities. To date, oral adverse events induced by these new anticancer therapies have been mainly reported using nonspecific terminology ("stomatitis," "mucosal inflammation," "mucositis") and remain poorly characterized, with the exception of mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis. Oral toxicities of targeted therapies often display very characteristic features which clearly differ from classic oral injuries observed with cytotoxic chemotherapy and/or radiotherapy. In addition, they frequently affect more than 20% of treated patients and can lead to a significant morbidity or permanent treatment discontinuation. Oral mucosal toxicities described in this review include mTOR inhibitor-associated stomatitis (mIAS); stomatitis, benign migratory glossitis, and osteonecrosis of the jaw associated with multi-targeted kinase inhibitors of the VEGF and PDGF receptors; mucositis induced by EGFR inhibitors (in monotherapy or in combination with head and neck radiotherapy and/or chemotherapy); hyperkeratotic lesions with BRAF inhibitors; pigmentary changes and lichenoid reactions secondary to imatinib; and more recent data on the "Osler-Weber-Rendu-like syndrome" described with the antibody-drug conjugate, TDM-1. Finally, we provide, to our knowledge, the first available structured data on oral toxicities induced by the new recently FDA- and EMA-approved monoclonal antibodies targeting PD-1. Clinical management of these targeted therapy-related oral changes is also discussed.

Impact of a planned dose interruption of dacomitinib in the treatment of advanced non-small-cell lung cancer (ARCHER 1042)

OBJECTIVES

Dacomitinib is a pan-HER inhibitor for advanced non-small-cell lung cancer (NSCLC). We explored the impact of a planned 4-day dacomitinib dose interruption on plasma exposure of dacomitinib and adverse events (AEs) of interest in Cohort III of the ARCHER 1042 study.

MATERIALS AND METHODS

Patients, treatment-naïve for advanced NSCLC with EGFR activating mutations, received oral dacomitinib 45mg QD (once daily). A planned dose interruption occurred in Cycle 1 from Days 11 through 14. The primary endpoint was the pharmacokinetic (PK) characteristics of dacomitinib in Cycle 1Day 10 and during dose interruption. Secondary endpoints included safety and concomitant medications used to treat AEs of interest.

RESULTS

Cohort III enrolled 25 patients. Median plasma C_max of dacomitinib in Cycle 1 Day 10 was 83.40ng/mL. Average median plasma dacomitinib concentration during the 4-day dose interruption was 42.63ng/mL. In the first 8 weeks of treatment 1) 80% of patients used concomitant medications for dermatologic AEs, 76% for diarrhea, and 44% for stomatitis, and 2) all patients experienced treatment-emergent AEs and 28% had all-causality Grade 3 AEs.

CONCLUSION

At 45mg QD dosing, PK parameters of plasma dacomitinib in Cycle 1 Day 10 were comparable to that obtained in Cycle 1 Day 14 from other dacomitinib studies. Average median plasma dacomitinib concentration during the 4-day dose interruption was approximately half of the median plasma C_max of dacomitinib observed prior to dose interruption. The toxicity profile was consistent with that from other studies of dacomitinib.

Autophagy in Diabetic Retinopathy

Autophagy is an important homeostatic cellular process encompassing a number of consecutive steps indispensable for degrading and recycling cytoplasmic materials. Basically autophagy is an adaptive response that under stressful conditions guarantees the physiological turnover of senescent and impaired organelles and, thus, controls cell fate by various cross-talk signals. Diabetic retinopathy (DR) is a serious microvascular complication of diabetes and accounts for 5% of all blindness. Although, various metabolic disorders have been linked with the onset of DR, due to the complex character of this multi-factorial disease, a connection between any particular defect and DR becomes speculative. Diabetes increases inflammation, advanced glycation end products (AGEs) and oxidative stress in the retina and its capillary cells. Particularly, a great number of evidences suggest a mutual connection between oxidative stress and other major metabolic abnormalities implicated in the development of DR. In addition, the intricate networks between autophagy and apoptosis establish the degree of cellular apoptosis and the progression of DR. Growing data underline the crucial role of reactive oxygen species (ROS) in the activation of autophagy. Depending on their delicate balance both redox signaling and autophagy, being detrimental or beneficial, retain opposing effects. The molecular mechanisms of autophagy are very complex and involve many signaling pathways cooperating at various steps. This review summarizes recent advances of the possible molecular mechanisms in autophagic process that are involved in pathophysiology of DR. In-depth analysis on the molecular mechanisms leading to autophagy in the retinal pigment epithelial (RPE) will be helpful to plan new therapies aimed at preventing or improving the progression of DR.

Topical Application of a Galenical Formulation for the Management of Everolimus-Induced Mucositis in Patients with Metastatic Cancer: a Retrospective Study

INTRODUCTION

Stomatitis is a common and potentially dose-limiting adverse event of the mammalian target of rapamycin (mTOR) inhibitor therapy. To minimize dose reductions or treatment delays that may affect therapeutic outcomes, management includes patient education, pain management strategies, and drug treatment. The aim of this study was to evaluate the effectiveness of a topically-applied galenical preparation to minimize the impact of everolimus-associated oral mucositis in patients with advanced cancer.

METHODS

Patients receiving everolimus plus exemestane for advanced breast cancer or everolimus alone for advanced renal cancer were eligible for inclusion. All patients were advised on procedures to maintain good oral hygiene and directed to use a dexamethasone-containing galenical preparation at the first signs of mucositis. Questionnaires were administered at baseline, and after cycles one, two, and three to evaluate the presence, duration, and intensity of oral mucositis.

RESULTS

Of the 19 patients included in the study (mean age 66 years; 16% male), mucositis developed in 10.5%, 47.4%, and 52.6% of patients after the first, second, and third cycles of everolimus, respectively. The median time to development of mucositis was 18.0 days, and the median time to mucositis resolution was 30.0 days. After the first, second, and third cycles of therapy, 5.3%, 10.5%, and 10.5% of patients required interruption of everolimus therapy; however, no dosage reductions for mucositis were necessary.

CONCLUSIONS

Patient education and the provision of an effective galenical preparation can minimize the effect of mTOR inhibitor-related mucositis.

Oral mucosal injury caused by mammalian target of rapamycin inhibitors: emerging perspectives on pathobiology and impact on clinical practice

In recent years oral mucosal injury has been increasingly recognized as an important toxicity associated with mammalian target of rapamycin (mTOR) inhibitors, including in patients with breast cancer who are receiving everolimus. This review addresses the state-of-the-science regarding mTOR inhibitor-associated stomatitis (mIAS), and delineates its clinical characteristics and management. Given the clinically impactful pain associated with mIAS, this review also specifically highlights new research focusing on the study of the molecular basis of pain. The incidence of mIAS varies widely (2-78%). As reported across multiple mTOR inhibitor clinical trials, grade 3/4 toxicity occurs in up to 9% of patients. Managing mTOR-associated oral lesions with topical oral, intralesional, and/or systemic steroids can be beneficial, in contrast to the lack of evidence supporting steroid treatment of oral mucositis caused by high-dose chemotherapy or radiation. However, steroid management is not uniformly efficacious in all patients receiving mTOR inhibitors. Furthermore, technology does not presently exist to permit clinicians to predict a priori which of their patients will develop these lesions. There thus remains a strategic need to define the pathobiology of mIAS, the molecular basis of pain, and risk prediction relative to development of the clinical lesion. This knowledge could lead to novel future interventions designed to more effectively prevent mIAS and improve pain management if clinically significant mIAS lesions develop.

Rapamycin: An InhibiTOR of Aging Emerges From the Soil of Easter Island

Rapamycin (sirolimus) is a macrolide immunosuppressant that inhibits the mechanistic target of rapamycin (mTOR) protein kinase and extends lifespan in model organisms including mice. Although rapamycin is an FDA-approved drug for select indications, a diverse set of negative side effects may preclude its wide-scale deployment as an antiaging therapy. mTOR forms two different protein complexes, mTORC1 and mTORC2; the former is acutely sensitive to rapamycin whereas the latter is only chronically sensitive to rapamycin in vivo. Over the past decade, it has become clear that although genetic and pharmacological inhibition of mTORC1 extends lifespan and delays aging, inhibition of mTORC2 has negative effects on mammalian health and longevity and is responsible for many of the negative side effects of rapamycin. In this review, we discuss recent advances in understanding the molecular and physiological effects of rapamycin treatment, and we discuss how the use of alternative rapamycin treatment regimens or rapamycin analogs has the potential to mitigate the deleterious side effects of rapamycin treatment by more specifically targeting mTORC1. Although the side effects of rapamycin are still of significant concern, rapid progress is being made in realizing the revolutionary potential of rapamycin-based therapies for the treatment of diseases of aging.

[Side effect management of tyrosine kinase inhibitors in urology : Gastrointestinal side effects]

For approximately one decade, tyrosinkinase inhibitors (TKIs, smart drugs) have dramatically changed and improved the treatment of patients suffering from metastasized renal cell carcinoma. However, the different drugs have substantial side effects. Especially gastrointestinal symptoms may be problematic for patients. These side effects represent a challenge for the physician. On the one hand, dosage modifications and treatment interruption should be avoided to minimize the risk for progression. On the other hand, only mild side effects are tolerable for the patient. Based on a literature review, a clear overview of the incidence of possible side effects for the drugs axitinib, cabozantinib, pazopanib, sorafenib, and sunitinib is provided. Furthermore, we give a practical guide on how to prevent and treat the different gastrointestinal side effects. Finally, it is pointed out when dosage modifications or interruption of treatment are necessary and how to expeditiously re-escalate the treatment after mitigation of side effects.

New frontiers in mucositis

Mucositis is among the most debilitating side effects of radiotherapy, chemotherapy, and targeted anticancer therapy. Research continues to escalate regarding key issues such as etiopathology, incidence and severity across different mucosae, relationships between mucosal and nonmucosal toxicities, and risk factors. This approach is being translated into enhanced management strategies. Recent technology advances provide an important foundation for this continuum. For example, evolution of applied genomics is fostering development of new algorithms to rapidly screen genomewide single-nucleotide polymorphisms (SNPs) for patient-associated risk prediction. This modeling will permit individual tailoring of the most effective, least toxic treatment in the future. The evolution of novel cancer therapeutics is changing the mucositis toxicity profile. These agents can be associated with unique mechanisms of mucosal damage. Additional research is needed to optimally manage toxicity caused by agents such as mammalian target of rapamycin (mTOR) inhibitors and tyrosine kinase inhibitors, without reducing antitumor effect. There has similarly been heightened attention across the health professions regarding clinical practice guidelines for mucositis management in the years following the first published guidelines in 2004. New opportunities exist to more effectively interface this collective guideline portfolio by capitalizing upon novel technologies such as an Internet-based Wiki platform. Substantive progress thus continues across many domains associated with mucosal injury in oncology patients. In addition to enhancing oncology patient care, these advances are being integrated into high-impact educational and scientific venues including the National Cancer Institute Physician Data Query (PDQ) portfolio as well as a new Gordon Research Conference on mucosal health and disease scheduled for June 2013.

Mechanism-based management for mucositis: option for treating side effects without compromising the efficacy of cancer therapy

Mucositis is a major side effect induced by chemotherapy and radiotherapy. Although mucositis is a leading cause of morbidity and mortality in cancer patients, management is largely limited to controlling symptoms, and few therapeutic agents are available for treatment. Since mucositis could be inhibited by the modulation of radiotherapy- or chemotherapy-induced pathways independently of cancer treatment, there is an opportunity for the development of more targeted therapies and interventions. This article examined potential therapeutic agents that have been investigated for the prevention and/or inhibition of mucositis induced by conventional chemotherapy and radiotherapy. They can be classified according to their mechanisms of action: scavenging reactive oxygen species, inhibition of specific cytokine production or inflammation, and inhibition of apoptosis. These early events may be good target pathways for preventing the pathogenesis of mucositis. Considering that both cancer therapy and therapeutic agents for mucositis act on both normal and cancer cells, agents that inhibit mucositis should act through mechanisms that selectively protect normal cells without compromising cancer treatment. Therefore, mechanism-based guidance for the treatment of mucositis is critical to prevent risky treatments for cancer patients and to relieve detrimental side effects effectively from cancer therapy.

A first in man, dose-finding study of the mTORC1/mTORC2 inhibitor OSI-027 in patients with advanced solid malignancies

BACKGROUND

The kinase activity of mTOR involves 2 multiprotein complexes, (mTORC1-mTORC2). Targeting mTORC1 with rapalogues induces compensatory feedback loops resulting in AKT/ERK activation, which may be abrogated by mTORC2 inhibition. A first-in-human trial evaluating tolerability, pharmacokinetics and pharmacodynamics of the dual TORC1/TORC2 inhibitor OSI-027 was conducted.

METHODS

Dose escalation was pursued for three schedules of administration (three consecutive days per week (S1), once a week (S2) and daily dosing (S3)), until dose-limiting toxicities (DLT) were identified. Expansion cohorts with paired tumour biopsies were initiated based on tolerability and pharmacodynamics.

RESULTS

One hundred and twenty eight patients with advanced cancer were enrolled. DLT consisted predominantly of fatigue, renal function disturbances and cardiac events. OSI-027 exposure was dose proportional, with Tmax within 4 h and a half-life of ∼14 h. Expansion cohorts were initiated for S1 and S2, as MTD for S3 was overall considered suboptimal. Target modulation in peripheral blood mononuclear cells were observed from 30 mg, but in tumour biopsies 120 mg QD were needed, which was a non-tolerable dose due to renal toxicity. No RECIST responses were recorded, with stable disease >6 months in six (5%) patients.

CONCLUSIONS

OSI-027 inhibits mTORC1/2 in patients with advanced tumour s in a dose-dependent manner but doses above the tolerable levels in S1 and S3 are required for a sustained biological effect in tumour biopsies.

Oral Mucositis Induced By Anticancer Therapies

Oral mucositis induced by conventional cytotoxic cancer therapies is a common and significant clinical problem in oncology. Mucositis symptoms, which include severe pain, may lead to dose reductions and unplanned interruptions of chemotherapy and/or radiotherapy, and often affect patients' quality of life. In addition, ulcerative mucositis represents a risk factor for local or systemic infectious complications that may be life-threatening in immunosuppressed patients. The development of biologically based targeted cancer therapies, which aim to block the growth, spread, and survival of tumors by interfering with specific molecular targets, may have reduced mucosal injury, but did not eliminate it. This article will review the epidemiology, pathobiology, and management of oral mucositis associated with conventional cytotoxic therapies for malignant diseases and will briefly summarize emerging information on oral mucosal injury associated with targeted therapies. Considerations for future research aimed at the development of more efficient and effective supportive care approaches will be presented, with emphasis on the contribution of dental researchers and clinicians in these efforts.

Recognition and Management of Oral Mucosal Injury Caused by Mammalian Target of Rapamycin Inhibitors: A Case Series

The mammalian target of rapamycin inhibitors (mTORIs) everolimus and temsirolimus are approved by the US Food and Drug Administration (FDA) for the treatment of various forms of advanced cancer, and the mTORI sirolimus is approved as an immunosuppressive agent for the prophylaxis of organ rejection in patients receiving renal transplants. The oral lesions associated with mTORI toxicity are distinct from the well-documented chemotherapy- and radiotherapy-induced mucositis, but they may often be misdiagnosed by medical oncologists or transplant physicians, potentially resulting in inappropriate management of this complication. mTORI-associated oral mucosal injury appears to be dose related, and its onset is consistently earlier than conventional mucositis associated with chemotherapy or radiation therapy. Although the lesions appear to resolve within approximately 2 weeks and do not seem to recur as severely with subsequent courses of therapy, the reduction in a patient's quality of life as a result of oral pain that affects the intake of nutritional foods should be taken into consideration. We report three cases that illustrate the complexity involved in the early assessment, referral, and appropriate management of mTORI-associated oral mucosal injury. Corticosteroids appear to be very useful in managing and perhaps preventing these lesions, whereas this approach has never shown efficacy in conventional chemotherapy-related mucositis. Early intervention to reduce the mTORI-associated oral mucosal injury is important to diminish the need for dose alterations of mTORIs and, therefore, to improve patient outcomes.

Dermatologic adverse events in pediatric patients receiving targeted anticancer therapies: a pooled analysis

BACKGROUND

The dermatologic adverse events (AEs) of various molecularly targeted therapies are well-described in adult cancer patients. Little has been reported on the incidence and clinical presentation of such AEs in pediatric patients with cancer. To address this gap, we analyzed the dermatologic AEs reported across clinical trials of targeted anticancer therapies in pediatric patients.

PROCEDURES

We conducted an electronic literature search (PubMed, American Society of Clinical Oncology annual meetings' abstracts, ClinicalTrials.gov, NCI's Pediatric Oncology Branch webpage) to identify clinical trials involving targeted anticancer therapies that reported dermatologic AEs in their safety data. Studies were limited to the pediatric population, monotherapy trials (oncology), and English language publications.

RESULTS

Pooled data from 19 clinical studies investigating 11 targeted anticancer agents (alemtuzumab, rituximab, imatinib, dasatinib, erlotinib, vandetanib, sorafenib, cabozantinib, pazopanib, everolimus, and temsirolimus) were analyzed. The most frequently encountered dermatologic AEs were rash (127/660; 19%), xerosis (18/100; 18%), mucositis (68/402; 17%), and pruritus (12/169; 7%). Other AEs included pigmentary abnormalities of the skin/hair (13%), hair disorders (trichomegaly, hypertrichosis, alopecia, and madarosis; 14%), urticaria (7%), palmoplantar erythrodysesthesia (7%), erythema, acne, purpura, skin fissures, other 'unknown skin changes', exanthem, infection, flushing, telangiectasia, and photosensitivity.

CONCLUSION

This study describes the dermatologic manifestations of targeted anticancer therapy-related AEs in the pediatric population. Since these AEs are often associated with significant morbidity, it is imperative that pediatric oncologists be familiar with their recognition and management, to avoid unnecessary dose modifications and/or termination, and to prevent impairments in patients' quality of life.

Everolimus plus exemestane for the treatment of advanced breast cancer: a review of subanalyses from BOLERO-2

Hormone receptor-positive breast cancer is typically managed with endocrine therapies. However, resistance to endocrine therapy results in disease progression in a large proportion of breast cancers. Through the understanding of the mechanisms of endocrine resistance, identification of implicated pathways and targets has led to the development of novel agents targeting these pathways. Phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway aberrations are common in breast cancer, with increased PI3K/AKT/mTOR signaling associated with resistance to endocrine and human epidermal growth factor receptor 2 (HER2)-targeted therapies. The mTOR inhibitor everolimus, in combination with exemestane, has been approved for patients with advanced hormone receptor-positive/HER2-negative breast cancer who progress on prior nonsteroidal aromatase inhibitor therapy based on results reported in the Breast Cancer Trials of Oral Everolimus-2 (BOLERO-2) study. This review will summarize the overall findings from BOLERO-2 and will consider available subanalyses by age, Asian origin, visceral or bone metastases, and prior therapy, with the aim of identifying populations most likely to benefit from everolimus therapy. The review will also summarize safety findings and their management and the effects of everolimus on quality of life.

Adverse event management of oral mucositis in patients with breast cancer

Oral mucositis (OM) is a clinically important and frequent adverse event (AE) associated with cancer treatment with conventional chemotherapy as well as new targeted agents. Incidence and severity of OM vary from treatment to treatment and from patient to patient. The pathogenesis of chemotherapy-induced OM can be divided into 5 phases. OM induced by targeted therapies differs among other things in appearance, course, concomitant AEs and toxicity, and thus could be perceived as an entity distinct from chemotherapy-induced OM with an innate pathogenic mechanism. OM has a severe impact on a patient's quality of life (QoL) by causing complications such as pain and discomfort. Even more important are associated restrictions in nutrition and hydration. Thus, the efficacy of cancer therapy might be impaired due to the necessity of dose delays and dose reductions. Numerous preventive and therapeutic approaches have been evaluated, but currently no single agent has changed the standard of care in preventing and treating OM. Thus, the current management has evolved from clinical experience rather than clinical evidence. This article will review the AE 'OM' induced by breast cancer treatment with chemotherapy and targeted agents in order to provide practical guidance for management and prevention.

Emerging evidence on the pathobiology of mucositis

BACKGROUND

Considerable progress has been made in our understanding of the biological basis for cancer therapy-induced mucosal barrier injury (mucositis). The last formal review of the subject by MASCC/ISOO was published in 2007; consequently, an update is timely.

METHODS

Panel members reviewed the biomedical literature on mucositis pathobiology published between January 2005 and December 2011.

RESULTS

Recent research has provided data on the contribution of tissue structure changes, inflammation and microbiome changes to the development of mucositis. Additional research has focused on targeted therapy-induced toxicity, toxicity clustering and the investigation of genetic polymorphisms in toxicity prediction. This review paper summarizes the recent evidence on these aspects of mucositis pathobiology.

CONCLUSION

The ultimate goal of mucositis researchers is to identify the most appropriate targets for therapeutic interventions and to be able to predict toxicity risk and personalize interventions to genetically suitable patients. Continuing research efforts are needed to further our understanding of mucositis pathobiology and the pharmacogenomics of toxicity.

Management of adverse events in patients with hormone receptor-positive breast cancer treated with everolimus: observations from a phase III clinical trial

Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of advanced renal cell carcinoma, pancreatic neuroendocrine tumors, subependymal giant cell astrocytoma associated with tuberous sclerosis complex, renal angiomyolipoma and tuberous sclerosis complex, and, in combination with exemestane, for hormone receptor-positive HER2-negative advanced breast cancer after failure of treatment with letrozole or anastrozole. Results from the phase III BOLERO-2 trial demonstrated that everolimus in combination with exemestane provided significant clinical benefit to patients with advanced hormone receptor-positive breast cancer. Although everolimus is generally well tolerated, as with most therapies administered in an advanced cancer setting, drug-related adverse events (AEs) inevitably occur. Most common AEs observed in the everolimus studies include stomatitis, rash, infection, noninfectious pneumonitis, and hyperglycemia. Clinical awareness and early identification of such AEs by oncology nurses are essential to dosing (interruptions, reduction, and treatment discontinuation); quality of life; and, ultimately, patient outcomes. Because everolimus has already been shown to significantly improve clinical efficacy in patients with advanced breast cancer, a proactive approach to the practical management of AEs associated with this mTOR inhibitor as well as other most common AEs observed in this patient population has been reviewed and outlined here.

Emerging evidence on the pathobiology of mucositis

BACKGROUND

Considerable progress has been made in our understanding of the biological basis for cancer therapy-induced mucosal barrier injury (mucositis). The last formal review of the subject by MASCC/ISOO was published in 2007; consequently, an update is timely.

METHODS

Panel members reviewed the biomedical literature on mucositis pathobiology published between January 2005 and December 2011.

RESULTS

Recent research has provided data on the contribution of tissue structure changes, inflammation and microbiome changes to the development of mucositis. Additional research has focused on targeted therapy-induced toxicity, toxicity clustering and the investigation of genetic polymorphisms in toxicity prediction. This review paper summarizes the recent evidence on these aspects of mucositis pathobiology.

CONCLUSION

The ultimate goal of mucositis researchers is to identify the most appropriate targets for therapeutic interventions and to be able to predict toxicity risk and personalize interventions to genetically suitable patients. Continuing research efforts are needed to further our understanding of mucositis pathobiology and the pharmacogenomics of toxicity.

Practical management of everolimus-related toxicities in patients with advanced solid tumors

Everolimus is an orally administered inhibitor of the mammalian target of rapamycin (mTOR), an intracellular protein kinase downstream of the phosphatidylinositol 3-kinase/AKT pathway involved in key components of tumorigenesis, including cell growth, proliferation, and angiogenesis. In the advanced cancer setting, based on favorable results from phase III trials, everolimus is indicated for the treatment of advanced renal cell carcinoma, advanced neuroendocrine tumors of pancreatic origin, and advanced hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer. Additional oncology indications for everolimus include renal angiomyolipoma with tuberous sclerosis complex and subependymal giant-cell astrocytoma. Although it is generally well tolerated, with most adverse events of mild to moderate severity and manageable, everolimus exhibits a distinct adverse event profile that warrants guidance for proper diagnostic and medical management. This guidance is particularly important given the potential for widespread long-term use of everolimus. This review will focus on the most relevant toxicities associated with mTOR inhibitors and on their management. Practical treatment recommendations are presented for stomatitis, noninfectious pneumonitis, rash, selected metabolic abnormalities, and infections. Provided these events are rapidly identified and treated, the vast majority should resolve with minimal effect on treatment outcomes and patients' quality of life.

New developments in mammalian target of rapamycin inhibitors for the treatment of sarcoma

Although sarcomas account for a small portion of solid malignancies, currently, there are few treatment options for sarcomas, particularly for advanced disease. The mammalian target of rapamycin (mTOR), a serine-threonine protein kinase in the phosphatidylinositol 3-kinase/serine/threonine protein kinase Akt signaling pathway, has an important role in the regulation of protein synthesis, cell proliferation, angiogenesis, and metabolism. Alterations of the mTOR signaling pathway are common in malignancies, including several types of sarcoma. Therefore, mTOR is a potentially important therapeutic target in these diseases. Rapamycin and its analogs (rapalogs) are effective anticancer agents in a broad range of preclinical models. Clinical trials with these agents alone and in combination with other anticancer agents, including chemotherapy and targeted therapies, have demonstrated potential clinical benefit in several types of sarcoma. The evidence from both preclinical and clinical studies supports further study of mTOR-targeting rapalogs in the treatment of various subtypes of sarcoma.

Swallowing dysfunction in cancer patients

PURPOSE

Dysphagia (swallowing dysfunction) is a debilitating, depressing, and potentially life-threatening complication in cancer patients that is likely underreported. The present paper is aimed to review relevant dysphagia literature between 1990 and 2010 with a focus on assessment tools, prevalence, complications, and impact on quality of life in patients with a variety of different cancers, particularly in those treated with curative chemoradiation for head and neck cancer.

METHODS

The literature search was limited to the English language and included both MEDLINE/PubMed and EMBASE. The search focused on papers reporting dysphagia as a side effect of cancer and cancer therapy. We identified relevant literature through the primary literature search and by articles identified in references.

RESULTS

A wide range of assessment tools for dysphagia was identified. Dysphagia is related to a number of factors such as direct impact of the tumor, cancer resection, chemotherapy, and radiotherapy and to newer therapies such as epidermal growth factor receptor inhibitors. Concomitant oral complications such as xerostomia may exacerbate subjective dysphagia. Most literature focuses on head and neck cancer, but dysphagia is also common in other types of cancer.

CONCLUSIONS

Swallowing impairment is a clinically relevant acute and long-term complication in patients with a wide variety of cancers. More prospective studies on the course of dysphagia and impact on quality of life from baseline to long-term follow-up after various treatment modalities, including targeted therapies, are needed.

Oral adverse events associated with tyrosine kinase and mammalian target of rapamycin inhibitors in renal cell carcinoma: a structured literature review

BACKGROUND

Oral adverse events (OAEs) associated with multitargeted tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin inhibitors (mTORIs) are underestimated but frequent and novel presentations of mucosal manifestations. Because optimal antitumor activity requires maintaining the optimal dose, it is essential to avoid unintended treatment delays or interruptions.

METHODS

We review the reported prevalence and appearance of OAEs with TKIs and mTORIs and the current oral assessment tools commonly used in clinical trials. We discuss the correlations between OAEs and hand-foot skin reaction (HFSR) and rash.

RESULTS

The reported prevalence of oral mucositis/stomatitis of any grade is 4% for pazopanib, 28% for sorafenib, 38% for sunitinib, 41% for temsirolimus, and 44% for everolimus. Oral lesions associated with these agents have been reported to more closely resemble aphthous stomatitis than OM caused by conventional agents. In addition, these agents may result in symptoms such as oral mucosal pain, dysgeusia, and dysphagia, in the absence of clinical lesions. Because of these factors, OAEs secondary to targeted agents may be underreported. In addition, a correlation between OAEs and HFSR was identified.

CONCLUSIONS

OAEs caused by TKIs and mTORIs may represent dose-limiting toxicities, especially considering the fact that even low grades of OAEs may be troubling to the patient. We discuss how these novel AEs can be assessed because current mucositis assessment tools have limitations. Prospective studies investigating the pathogenesis, risk factors, and management of OAEs are needed in order to minimize the impact on patient's health-related quality of life.

Phase I study for ridaforolimus, an oral mTOR inhibitor, in Japanese patients with advanced solid tumors

Purpose

Ridaforolimus is a non-prodrug mTOR inhibitor. The safety, pharmacokinetics (PK), and antitumor activity of oral ridaforolimus were assessed in Japanese patients with refractory solid tumors.

Methods

Ridaforolimus (20 or 40 mg) was administered as a single dose on Day 1, followed by once daily dosing five times a week for a 3-week cycle beginning on Day 8. Full PK sampling was performed on Days 1 and 26.

Results

Thirteen patients (7 at 20 mg and 6 at 40 mg) were enrolled. The median treatment duration was 82 days. The most common drug-related adverse events were stomatitis, hypertriglyceridemia, and proteinuria. Two patients had dose-limiting toxicities (grade 3 stomatitis at 20 mg, and grade 3 anorexia and vomiting at 40 mg). Four patients had grade 1 interstitial pneumonitis. Ridaforolimus in the whole blood was rapidly absorbed and slowly eliminated with a half-life of approximately 56–58 h after a single dose. Two patients (with non-small cell lung cancer and angiosarcoma, respectively) achieved a partial response, and five patients (one with thymic cancer and four with soft tissue sarcomas) had a stable disease for ≥16 weeks.

Conclusions

Ridaforolimus was well tolerated up to a dose of 40 mg in Japanese patients. Preliminary evidence of antitumor activity was observed for patients with solid tumors. Further investigation at this dose is warranted.

Potential Therapeutic Roles for Inhibition of the PI3K/Akt/mTOR Pathway in the Pathophysiology of Diabetic Retinopathy

Novel therapeutics such as inhibitors of PI3K/Akt/mTOR pathway presents a unique opportunity for the management of diabetic retinopathy (DR). Second generation mTOR inhibitors have the prospect to be efficacious in managing various stages of disease progression in DR. During early stages, the mTOR inhibitors suppress HIF-1α, VEGF, leakage, and breakdown of the blood-retinal barrier. These mTOR inhibitors impart a pronounced inhibitory effect on inflammation, an early component with diverse ramifications influencing the progression of DR. These inhibitors suppress IKK and NF-κB along with downstream inflammatory cytokines, chemokines, and adhesion molecules. In proliferative DR, mTOR inhibitors suppress several growth factors that play pivotal roles in the induction of pathological angiogenesis. Lead mTOR inhibitors in clinical trials for ocular indications present an attractive treatment option for chronic use in DR with favorable safety profile and sustained ocular pharmacokinetics following single dose. Thereby, reducing dosing frequency and risk associated with chronic drug administration.

Common toxicities of mammalian target of rapamycin inhibitors

The toxicities of newer targeted therapies are different from those seen with the traditional chemotherapy. Mammalian target of rapamycin (mTOR) inhibitors are evolving into an important class of drugs in oncology, and this class of drugs presents with a variety of different toxicities. Although similar to the toxicities seen in transplantation, these rapamycin analogs have unique side effects when compared to traditional chemotherapy agents. While most of the toxicities are mild, few can be severe and require routine monitoring. Mucositis and rash are the most common side effects. The metabolic toxicities, hyperglycemia, hyperlipidemia, and hypophosphatemia are different from the side effects traditionally seen with chemotherapy. This review will focus on the common toxicities seen with the mTOR inhibitors.

Oral mucositis: the new paradigms

PURPOSE OF REVIEW

Mucositis has long been viewed as an unavoidable consequence of high-dose chemotherapy and/or radiation. Management has been directed to supportive care including oral pain control, nutritional support, infection treatment and control of diarrhea. Whereas these interventions have been valuable for clinical management, they have not been collectively directed to molecularly targeted prevention and treatment. This review addresses recent advances regarding mucosal injury in cancer patients, with emphasis on symptom clusters, genetically based tissue susceptibility and risk prediction, imaging technology, and computational biology.

RECENT FINDINGS

Modeling of symptom clusters in cancer patients continues to mature. Although integration of mucositis into the paradigm is at an early stage, recent studies suggest that important molecular and clinical insights will emerge in this regard. Initial studies of genetic-based tissue risk are also providing a research basis that may lead to clinical risk prediction models. These advances are in part being engineered via new imaging and computational biology technologies, drawing upon literature in nonmucositis systems. Just as the past decade has been hallmarked by linkage of pathobiology with clinical expression of mucosal toxicity, the next decade promises to identify new molecular interactions and risk prediction models based on novel application of the analytic technologies.

SUMMARY

Recent research has culminated in convergence of molecular pathobiology with models of symptom clusters, genetic-based risk, and imaging and computational biology. The field is poised to further delineate this paradigm, with the goal of development of molecularly targeted drugs and devices for mucositis management.