Complex renal cysts associated with crizotinib treatment

Nephrotoxicity of targeted therapy used to treat lung cancer

Lung cancer is the leading cause of cancer-related death worldwide, especially non-small cell lung cancer. Early diagnosis and better treatment choices have already provided a more promising prognosis for cancer patients. In targeted therapy, antagonists target specific genes supporting cancer growth, proliferation and metastasis. With the incorporation of targeted therapies in routine cancer therapy, it is imperative that the array of toxicities associated with these agents must be well-recognized and managed, especially since these toxicities are distinct from those seen with conventional cytotoxic agents. Drug-related nephrotoxicity has attracted attention when initiating cancer therapy. Our review aims to summarize the adverse renal effects caused by targeted therapy during lung cancer treatment, mainly focusing on EGFR and ALK tyrosine kinase inhibitors. Also, we discuss the possible mechanism of the side effect and provide managements to help improve the renal function in clinical practice.

Cancer drugs and acute kidney injury: new therapies and new challenges

PURPOSE OF REVIEW

Cancer therapies continue to evolve at a rapid pace and although novel treatments, including immunotherapies and targeted therapies have allowed for substantial improvements in cancer survival, they carry associated risks of acute kidney injury (AKI). We aim to summarize the existing literature on AKI associated with the spectrum of systemic cancer treatments, including conventional chemotherapies, newer immunotherapies, and the growing number of targeted cancer therapies, which may be associated with both AKI and 'pseudo-AKI'.

RECENT FINDINGS

Conventional cytotoxic chemotherapies (e.g. cisplatin and other platinum-based agents, methotrexate, pemetrexed, ifosfamide, etc.) with well recognized nephrotoxicities (predominantly tubulointerstitial injury) remain in widespread use. Immunotherapies (e.g., immune checkpoint inhibitors and CAR-T therapies) may be associated with kidney immune-related adverse events, most often acute interstitial nephritis, and rarely, glomerular disease. Recently, multiple targeted cancer therapies have been associated with reduced renal tubular secretion of creatinine, causing elevations in serum creatinine and apparent 'pseudo-AKI'. To complicate matters further, these agents have had biopsy-proven, 'true' kidney injury attributed to them in numerous case reports.

SUMMARY

Clinicians in nephrology and oncology must be aware of the various potential kidney risks with these agents and recognize those with clinically meaningful impact on both cancer and kidney outcomes.

Development of crizotinib-associated renal cyst in a non-small cell lung cancer patient with ALK fusion: a case report and review of the literature

BACKGROUND

Crizotinib, an oral first-generation tyrosine kinase inhibitor (TKI), is superior to systemic chemotherapy for the treatment of non-small cell lung cancer (NSCLC) with positive rearrangement of anaplastic lymphoma kinase (ALK). However, an increased incidence of renal and hepatic cysts has been reported in the patients on crizotinib treatment.

CASE PRESENTATION

Here, we describe a case of a 71-year-old Chinese women developed multiple cystic lesions in kidney and liver during crizotinib treatment for the primary and metastatic NSCLC. The renal and hepatic cysts were noted by CT scan 3 months after crizotinib treatment, which were spontaneously and significantly regressed after stopping crizotinib.

CONCLUSIONS

Based on literature review and our experience in this case report, we concluded that crizotinib-associated renal cyst (CARCs) has features of malignancy and abscess in radiographic imaging, and thus, pathological confirmation is necessary to avoid inappropriate treatment decision. In addition, to benefit the patients with progress-free survival (PFS), switching from crizotinib to alectinib is recommended for the treatment of NSCLC patients who developed CARCs.

From Development to Place in Therapy of Lorlatinib for the Treatment of ALK and ROS1 Rearranged Non-Small Cell Lung Cancer (NSCLC)

Following the results of the CROWN phase III trial, the third-generation macrocyclic ALK inhibitor lorlatinib has been introduced as a salvage option after the failure of a first-line TKI in ALK-rearranged NSCLC, while its precise role in the therapeutic algorithm of ROS1 positive disease is still to be completely defined. The ability to overcome acquired resistance to prior generation TKIs (alectinib, brigatinib, ceritinib, and crizotinib) and the high intracranial activity in brain metastatic disease thanks to increased blood-brain barrier penetration are the reasons for the growing popularity and interest in this molecule. Nevertheless, the major vulnerability of this drug resides in a peculiar profile of related collateral events, with neurological impairment being the most conflicting and debated clinical issue. The cognitive safety concern, the susceptibility to heterogeneous resistance pathways, and the absence of a valid alternative in the second line are strongly jeopardizing a potential paradigm shift in this oncogene-addicted disease. So, when prescribing lorlatinib, clinicians must face two diametrically opposed characteristics: a great therapeutic potential without the intrinsic limitations of its precursor TKIs, a cytotoxic activity threatened by suboptimal tolerability, and the unavoidable onset of resistance mechanisms we cannot properly manage yet. In this paper, we give a critical point of view on the stepwise introduction of this promising drug into clinical practice, starting from its innovative molecular and biochemical properties to intriguing future developments, without forgetting its weaknesses.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

Silibinin Suppresses the Hyperlipidemic Effects of the ALK-Tyrosine Kinase Inhibitor Lorlatinib in Hepatic Cells

The third-generation anaplastic lymphoma tyrosine kinase inhibitor (ALK-TKI) lorlatinib has a unique side effect profile that includes hypercholesteremia and hypertriglyceridemia in >80% of lung cancer patients. Here, we tested the hypothesis that lorlatinib might directly promote the accumulation of cholesterol and/or triglycerides in human hepatic cells. We investigated the capacity of the hepatoprotectant silibinin to modify the lipid-modifying activity of lorlatinib. To predict clinically relevant drug−drug interactions if silibinin were used to clinically manage lorlatinib-induced hyperlipidemic effects in hepatic cells, we also explored the capacity of silibinin to interact with and block CYP3A4 activity using in silico computational descriptions and in vitro biochemical assays. A semi-targeted ultrahigh pressure liquid chromatography accurate mass quadrupole time-of-flight mass spectrometry with electrospray ionization (UHPLC-ESI-QTOF-MS/MS)-based lipidomic approach revealed that short-term treatment of hepatic cells with lorlatinib promotes the accumulation of numerous molecular species of cholesteryl esters and triglycerides. Silibinin treatment significantly protected the steady-state lipidome of hepatocytes against the hyperlipidemic actions of lorlatinib. Lipid staining confirmed the ability of lorlatinib to promote neutral lipid overload in hepatocytes upon long-term exposure, which was prevented by co-treatment with silibinin. Computational analyses and cell-free biochemical assays predicted a weak to moderate inhibitory activity of clinically relevant concentrations of silibinin against CYP3A4 when compared with recommended (rosuvastatin) and non-recommended (simvastatin) statins for lorlatinib-associated dyslipidemia. The elevated plasma cholesterol and triglyceride levels in lorlatinib-treated lung cancer patients might involve primary alterations in the hepatic accumulation of lipid intermediates. Silibinin could be clinically explored to reduce the undesirable hyperlipidemic activity of lorlatinib in lung cancer patients.

Renal Abscess Caused by Crizotinib: A Rare Case Report

Crizotinib is a tyrosine kinase inhibitor that has been found to be effective in the treatment of c-ros oncogene 1-positive non-small cell lung cancer. Although this targeted agent for treating cancer has shown superiority to standard chemotherapy in some ways, this drug has adverse effects, such as the development of renal abscesses. Some associated renal damage may disappear with crizotinib withdrawal. Hence, we present the case of a 58-year-old man with non-small cell lung cancer on crizotinib therapy who developed bilateral renal abnormal space-occupying lesions, successively which were difficult to identify using various imaging methods; even PET-CT highly suspected the right renal masses as malignant. Finally, the right renal lesions were confirmed as renal abscesses by postoperative pathology. The left renal lesion was considered as renal cysts through the lesion disappearing after crizotinib withdrawal. There have been very few reports in this respect, especially proved by various methods and confirmed by postoperative pathology. It is important to recognize this drug-related complication in order to avoid incorrect diagnosis and inadequate therapy. It is necessary to monitor renal changes after taking crizotinib.

Anaplastic lymphoma kinase inhibitors and their effect on the kidney

Lung cancer is the leading cause of cancer-related mortality and approximately 5% of non–small-cell lung cancer (NSCLC) patients are positive for anaplastic lymphoma kinase (ALK) gene rearrangement or fusion with echinoderm microtubule-associated protein-like 4. ALK inhibitors are the mainstay treatment for patients with NSCLC harboring a rearrangement of the ALK gene or the ROS1 oncogenes. With the recent publication of pivotal trials leading to the approval of these compounds in different indications, their toxicity profile warrants an update. Several ALK-1 inhibitors are used in clinical practice, including crizotinib, ceritinib and alectinib. According to the package insert and published literature, treatment with several ALK-1 inhibitors appears to be associated with the development of peripheral edema and rare electrolyte disorders, kidney failure, proteinuria and an increased risk for the development and progression of renal cysts. This review introduces the different types of ALK inhibitors, focusing on their detailed kidney-related side effects in clinical practice.

Nephrotoxicity of cancer therapeutic drugs: Focusing on novel agents

Kidney injury caused by anticancer agents is a common problem that can interfere with and affect the dose intensity of anticancer therapy, thus restricting patient survival. Recent advances in targeted and immunotherapeutic agents have transformed the landscape of medical oncology, and these agents have been widely employed in clinical practice. While typically associated with favorable toxicity profiles, several novel anticancer drugs present distinctive nephrotoxicities. It remains urgent to closely monitor renal injuries associated with these agents, and medical practitioners should be familiar with general principles for managing nephrotoxicity associated with novel cancer drugs. This review provides an in-depth investigation of the literature and guidelines regarding the prevalence, clinical presentations, mechanisms, and management of nephrotoxicity for each drug.

Crizotinib-associated renal cyst development may be associated with prolonged progression-free survival in patients with ALK-positive non-small-cell lung cancer: Case report and review of the literature

Non-small cell lung cancer patients with anaplastic lymphoma kinase or c-ros oncogene 1 mutations who are treated with the tyrosine kinase inhibitor crizotinib rarely develop crizotinib-associated renal cysts (CARCs). Here, we present a case report and review of the literature supporting the hypothesis that CARCs may correlate positively with progression-free survival.

Complex renal cysts combined with hemorrhage during crizotinib treatment for ALK-rearranged lung adenocarcinoma

The oral small-molecule tyrosine kinase inhibitor (TKI), crizotinib has been approved as a first-generation anaplastic lymphoma kinase (ALK) inhibitor in treatment of advanced ALK-positive non-small cell lung cancer (NSCLC). Recently, development of complex renal cysts has been reported with crizotinib usage, highlighting the importance of accurate differentiation between complex renal cysts and new metastasis in NSCLC. Here we describe a case study with confirmed EGFR wild-type and ALK-rearranged lung adenocarcinoma who developed complex renal cysts combined with hemorrhage during crizotinib treatment, with no abnormal clinical symptoms or kidney functions observed. Interestingly, without crizotinib treatment termination or reduction, the complex hemorrhagic renal cysts regressed with self-limiting and healing. The combined usage of ultrasound, CT and MRI techniques in the presented case allowed proper monitoring of the internal changes within complex renal cysts. The patient provided written informed consent authorizing publication of clinical case. Thus, better understanding of the imaging features of crizotinib-related renal cysts combined with hemorrhage would avoid misdiagnoses as a new metastatic renal mass or the aggravation of the primary disease, therefore avoiding further invasive investigation.

Crizotinib-associated Renal Cyst Formation in a Pediatric Patient With ALK+ Epithelioid Inflammatory Myofibroblastic Sarcoma

BACKGROUND

Crizotinib is a first-generation tyrosine kinase inhibitor used for anaplastic lymphoma kinase (ALK) positive cancers. Simple and complex renal cyst formation is a rare complication of crizotinib use that has been reported previously in the adult population.

CASE

We report a case of a right renal mass in a 17-year-old with ALK-positive epithelioid inflammatory myofibroblastic sarcoma treated with Crizotinib. After cessation of Crizotinib and initiating Alectenib, a second generation ALK inhibitor, the mass decreased in size and the patient remained asymptomatic without evidence of recurrence at three months of follow-up.

Alectinib Induced Regression of Renal and Hepatic Cysts Caused by Crizotinib

Background

Crizotinib is the first tyrosine kinase inhibitor approved for the treatment of anaplastic lymphoma kinase (ALK) rearranged non-small cell lung cancer (NSCLC). An increased incidence of renal cysts has been described during the crizotinib treatment.

Case Presentation

We herein report the case of a 74-year-old woman who received crizotinib for metastatic ALK-positive NSCLC. During the crizotinib treatment, complex renal cystic lesions with invasion of perirenal spaces and iliopsoas muscle appeared; two complex hepatic cysts were also observed. Almost all lesions disappeared after switching to alectinib, a second-generation ALK inhibitor.

Conclusion

It would seem that alectinib is able to reduce in size and number hepatic and renal cysts caused by the crizotinib treatment. Nevertheless, further studies are needed to clarify the role of both crizotinib in the onset of renal and hepatic cysts and alectinib in their disappearance.

Renal complication of crizotinib: Crizotinib-associated complex renal cyst

Crizotinib is one of the first generations of tyrosine kinase inhibitors targeting anaplastic lymphoma kinase(ALK) and is recently found to be associated with the development of complex renal cysts with inconclusive explanation up to this time. Hereby, we discuss the hypothesis of Crizotinib-associated complex renal cyst development and coexisting renal impairment after initiation of the treatment in a 75-year-old man with ALK-positive non-small cell lung cancer whose complex renal cysts evolved after initiation and cessation of Crizotinib treatment. The coexistence as renal impairment persisted even after switching from Crizotinib to Ceritinib.

Nephrotoxic Chemotherapy Agents: Old and New

In the last several decades, advancements in chemotherapy have improved the overall survival of cancer patients. These agents, however, are associated with adverse effects, including various kidney lesions. This review summarizes the nephrotoxic potential of chemotherapy agents, old and new, as well as the different factors that contribute to kidney injury. Provided for each class of chemotherapy agent is the associated kidney lesion and a brief discussion of clinical manifestation, mechanism of action, and possible treatment when available. Understanding the nephrotoxic potential of these agents have on the kidneys is imperative for both the oncologist and the nephrologist to properly care for cancer patients and ensure their best outcomes.

[Renal toxicities of targeted therapies in oncology]

The advent of new molecules oncology including targeted therapies, has resulted in improved patient survival over standard chemotherapy. The renal toxicities of these anticancer agents are more and more recognized and vary according to the targeted therapeutic target. This article reviews the renal toxicity associated with targeted anticancer therapies directed against Epidermal growth factor receptor, Human epidermal growth factor-2, B-rapidly accelerated fibrosarcoma, Mitogen-activated protein kinase, Anaplastic lymphoma kinase, Programmed cell death-1/programmed cell death ligand-1, Cytotoxic T lymphocyte antigen-4 and Vascular endothelial growth factor/receptor. The early diagnosis and management of these renal adverse events is essential for the clinician who cares for such patients.

Complete response to crizotinib in a metastatic adenocarcinoma of unknown primary harboring MET amplification and NTRK1 co-occurring mutation

Carcinomas of unknown primary (CUPs) have poor prognosis due to the paucity of data on their clinical characteristics and laboratory features, and empirical chemotherapy still remains the critical management for this kind of disease. This study aimed to present the knowledge of treating an elderly man with metastatic adenocarcinoma of unknown primary and also with a history of long-term hypertension and renal cysts. He was identified to harbor mesenchymal-epithelial transition factor (MET) gene amplification and neurotrophic tyrosine receptor kinase 1 (NTRK1) gene co-occurring mutation by targeted next-generation sequencing analysis upon the progression of empirical chemotherapy. He was then treated with a standard dose of crizotinib (250 mg, twice daily), which exhibited a satisfactory complete response (CR) of the targeted lesions after 1 month of treatment. When the number of renal cysts increased and renal inadequacy occurred after treatment for 2 months, crizotinib was reduced to half-dose (250 mg, once daily), and still conferred maintenance of CR for another 6.5 months and good quality life of the patient. These results suggested that treatments based on driver genes rather than primary tumor types could be a promising manipulation for achieving better treatment outcome, and a half-dose of crizotinib might be both effective and tolerable for MET-overexpressed CUPs with underlying renal diseases.

Renal Injury during Long-Term Crizotinib Therapy

Crizotinib is highly effective against anaplastic lymphoma kinase-positive and c-ros oncogen1-positive non-small cell lung cancer. Renal dysfunction is associated with crizotinib therapy but the mechanism is unknown. Here, we report a case of anaplastic lymphoma kinase positive non-small cell lung cancer showing multiple cysts and dysfunction of the kidneys during crizotinib administration. We also present results demonstrating that long-term crizotinib treatment induces fibrosis and dysfunction of the kidneys by activating the tumor necrosis factor-α/nuclear factor-κB signaling pathway. In conclusion, this study shows the renal detrimental effects of crizotinib, suggesting the need of careful monitoring of renal function during crizotinib therapy.

Bosniak Category III Renal Cysts Caused by Crizotinib in an Anaplastic Lymphoma Kinase Gene-Rearranged Non-Small Cell Lung Cancer Patient

Bosniak category III renal cystic masses are often treated with surgical resection because of high risk of malignancy. Crizotinib is an anaplastic lymphoma kinase (ALK) inhibitor used to treat ALK gene-rearranged non-small cell lung cancer and reported to be associated with complex renal cyst formation. We herein report a case of Bosniak category III renal cysts occurred in a crizotinib-treated ALK gene-rearranged non-small cell lung cancer patients. The cysts regressed spontaneously after cessation of crizotinib and we could thus avoid unnecessary surgical resection.

Regression of Crizotinib-Associated Complex Cystic Lesions after Switching to Alectinib

Crizotinib, which is effective in patients with anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer, is sometimes associated with the generation of complex renal cysts. A 56-year-old man with ALK positive adenocarcinoma received crizotinib. Ten months after the introduction of crizotinib, a cystic lesion developed from his right kidney to the iliopsoas muscle, accompanied by fever, anemia, and hypoproteinemia. After 17 months of treatment, crizotinib was switched to alectinib, followed by the recovery of hypoproteinemia and systemic inflammation. Switching to alectinib may be beneficial in patients demonstrating crizotinib-associated complex renal cysts with systemic inflammation and exhaustion.

Final results of the large-scale multinational trial PROFILE 1005: efficacy and safety of crizotinib in previously treated patients with advanced/metastatic ALK-positive non-small-cell lung cancer

PURPOSE

Crizotinib is a potent, orally administered tyrosine kinase inhibitor approved for the treatment of anaplastic lymphoma kinase (ALK)-positive advanced non-small-cell lung cancer (NSCLC). We report final results from PROFILE 1005, the largest clinical trial to date for an ALK inhibitor in ALK-positive NSCLC.

PATIENTS AND METHODS

PROFILE 1005 (NCT00932451) was a multicenter, single-arm phase 2 trial of the efficacy, safety and tolerability of crizotinib (250 mg twice daily; 3 week continuous treatment cycles) in patients with ALK-positive NSCLC after failure of ≥1 lines of systemic treatment for locally advanced/metastatic disease. Patients' tumour ALK status was initially determined by a central laboratory until a protocol amendment permitted enrolment of patients based on locally determined ALK status. Co-primary endpoints were objective response rate (ORR), evaluated using Response Evaluation Criteria in Solid Tumours V.1.1 and adverse events (AEs). Cancer-specific patient-reported outcomes (PROs) were also assessed using the European Organisation for the Research and Treatment of Cancer QLQ-C30 and its lung cancer module QLQ-LC13.

RESULTS

1069 patients were enrolled; 1066 received crizotinib. The as-treated population comprised 908 and 158 patients, in whom tumour positive ALK-status was determined centrally (± locally) or locally only, respectively. At baseline, a majority of patients were <65 years (84%), 66% were never smokers and 46% were Asian. Derived investigator-assessed ORR was 54% (95% CI 51 to 57) and 41% (95% CI 33 to 49) in the central-testing and local-testing subgroups, respectively. The most common treatment-related AEs in the overall population (any grade) were vision disorder (58%), nausea (51%), diarrhoea (47%) and vomiting (47%). PRO scores demonstrated clinically meaningful improvement in lung cancer symptoms and global quality of life.

CONCLUSION

The efficacy, safety and PRO profiles of crizotinib in this cohort of 1066 patients with ALK-positive NSCLC are consistent with previous reports.

TRIAL REGISTRATION NUMBER

Phase 2 trial (NCT00932451); Results.

Kidney Toxicities Associated With Novel Cancer Therapies

Targeted therapies that act via unique molecular pathways and interfere with cancer cell growth and tumor progression have dramatically changed the cancer treatment paradigm. However, although, ideally, these therapies intend to target only cancer cells, they do often affect nonmalignant tissue. Numerous renal side effects have been reported to date. This article will review clinical presentation, presumed pathophysiology, and treatment of kidney side effects of targeted therapies. Feasibility of the continuation of cancer therapy despite renal toxicity will also be addressed.

Crizotinib: Renal Safety Evaluation

Anaplastic lymphoma kinase 1 (ALK 1) is a member of the insulin receptor tyrosine kinase family. Crizotinib is a small molecule inhibitor available for clinical use, which is found within the ALK family of drugs. Several other ALK 1 inhibitors are currently being evaluated in preclinical and clinical trials. Crizotinib is approved for the treatment of advanced ALK positive non-small cell lung cancer (NSCLC). However, this drug is associated with various renal adverse effects. Treatment with crizotinib appears to be associated with pseudo- and true acute kidney injury. Peripheral edema and rare electrolyte disorders are also described with this ALK inhibitor. Finally, crizotinib also appears to increase the risk for the development and progression of renal cysts. This review focuses on the mechanism of action, clinical indications, pharmacology, and adverse renal effects of crizotinib.

Crizotinib Associated Renal Cysts [CARCs]: incidence and patterns of evolution

Background

Novel therapeutic agents recently introduced for the treatment of cancer have several unusual side effects. An increased incidence of renal cystic lesions, often with features concerning for malignancy or infection, has been reported in patients with anaplastic lymphoma kinase (ALK) - rearranged advanced non-small cell lung cancer (NSCLC) treated with Crizotinib. Many of these lesions undergo spontaneous resolution despite developing complex features on imaging. We assess the incidence and patterns of evolution of Crizotinib Associated Renal Cysts [CARCs] at our institute and provide histopathology correlation of their benign nature.

Methods

A retrospective analysis of renal lesions in computerised tomography (CT) scans of 35 patients with advanced ALK-rearranged NSCLC who had been prescribed crizotinib at our institution was performed by three radiologists, who analysed the evolution of these lesions, particularly for pre-defined significant and complex changes.

Results

Of 26 patients eligible for this analysis, 4 (15%) had cysts at baseline that remained stable on crizotinib treatment while 11(42%) developed significant change in 28 renal cysts. Commonest pattern of cyst evolution was enlargement from baseline followed by spontaneous regression (17/28 lesions) while other patterns noted were stable lesions, regression from baseline and ongoing enlargement. The median maximum size reached was 23 mm (range 9 – 67 mm) after a median of 178 days (160 to 1342) on crizotinib. Complex change occurred in 12 cysts, in 7/26 (27%) patients and within 60 days of starting Crizotinib in 10 cysts. Imaging features were falsely concerning for malignancy or abscess in 4/26 patients.

Conclusion

Most CARCs resolve spontaneously, or have a benign evolution despite enlargement and other features concerning for malignancy or infection on imaging. This unusual manifestation of chemotherapy should be recognised, particularly by radiologists, so that inappropriate treatment decisions are avoided.

Renal cyst formation in patients treated with crizotinib for non-small cell lung cancer-Incidence, radiological features and clinical characteristics

Treatment with the ALK inhibitor crizotinib has been associated with complex renal cyst formation in patients with non-small cell lung cancer (NSCLC). Using patients treated with crizotinib, we aimed to evaluate the incidence of renal cyst formation, to identify risk factors for cyst formation and to provide a radiological description of cyst characteristics. Patients with ALK-positive NSCLC treated with crizotinib were retrospectively identified from an institutional database. Computed tomography (CT) imaging performed prior to and during crizotinib treatment was retrospectively reviewed to assess the size and complexity of pre-existing cysts, new cysts, and enlarging cysts. Demographic data including age, sex, ethnicity, smoking history and length of treatment were also recorded. Data from 60 patients with NSCLC treated with crizotinib at our institution between 6/5/2009 and 7/1/2015 were collected. 57 had CT imaging before and during treatment. Mean length of imaging follow-up was 18 months. 9 (16%) patients had cysts which enlarged or developed de novo during treatment. 2 (4%) patients developed complex renal cysts (1 of these patients also developed complex hepatic cysts). Female gender (p=0.008) and the presence of renal cysts on baseline scans (p=0.044) were significantly associated with cyst formation or growth. Renal cyst formation or growth occurred in 16% of crizotinib-treated patients. Women and those with pre-existing cysts were at greatest risk. Although the potential causal relationship between crizotinib use and renal cyst formation has yet to be fully defined, it is important for radiologists and clinicians to be aware of this finding.

Evolving Cancer Classification in the Era of Personalized Medicine: A Primer for Radiologists

Traditionally tumors were classified based on anatomic location but now specific genetic mutations in cancers are leading to treatment of tumors with molecular targeted therapies. This has led to a paradigm shift in the classification and treatment of cancer. Tumors treated with molecular targeted therapies often show morphological changes rather than change in size and are associated with class specific and drug specific toxicities, different from those encountered with conventional chemotherapeutic agents. It is important for the radiologists to be familiar with the new cancer classification and the various treatment strategies employed, in order to effectively communicate and participate in the multi-disciplinary care. In this paper we will focus on lung cancer as a prototype of the new molecular classification.

Renal Toxicities of Targeted Therapies

With the incorporation of targeted therapies in routine cancer therapy, it is imperative that the array of toxicities associated with these agents be well-recognized and managed, especially since these toxicities are distinct from those seen with conventional cytotoxic agents. This review will focus on these renal toxicities from commonly used targeted agents. This review discusses the mechanisms of these side effects and management strategies. Anti-vascular endothelial growth factor (VEGF) agents including the monoclonal antibody bevacizumab, aflibercept (VEGF trap), and anti-VEGF receptor (VEGFR) tyrosine kinase inhibitors (TKIs) all cause hypertension, whereas some of them result in proteinuria. Monoclonal antibodies against the human epidermal growth factor receptor (HER) family of receptors, such as cetuximab and panitumumab, cause electrolyte imbalances including hypomagnesemia and hypokalemia due to the direct nephrotoxic effect of the drug on renal tubules. Cetuximab may also result in renal tubular acidosis. The TKIs, imatinib and dasatinib, can result in acute or chronic renal failure. Rituximab, an anti-CD20 monoclonal antibody, can cause acute renal failure following initiation of therapy because of the onset of acute tumor lysis syndrome. Everolimus, a mammalian target of rapamycin (mTOR) inhibitor, can result in proteinuria. Discerning the renal adverse effects resulting from these agents is essential for safe treatment strategies, particularly in those with pre-existing renal disease.

Adverse Renal Effects of Novel Molecular Oncologic Targeted Therapies: A Narrative Review

Novel targeted anti-cancer therapies have resulted in improvement in patient survival compared to standard chemotherapy. Renal toxicities of targeted agents are increasingly being recognized. The incidence, severity, and pattern of renal toxicities may vary according to the respective target of the drug. Here we review the adverse renal effects associated with a selection of currently approved targeted cancer therapies, directed to EGFR, HER2, BRAF, MEK, ALK, PD1/PDL1, CTLA-4, and novel agents targeted to VEGF/R and TKIs. In summary, electrolyte disorders, renal impairment and hypertension are the most commonly reported events. Of the novel targeted agents, ipilumumab and cetuximab have the most nephrotoxic events reported. The early diagnosis and prompt recognition of these renal adverse events are essential for the general nephrologist taking care of these patients.

Antineoplastic Treatment and Renal Injury: An Update on Renal Pathology Due to Cytotoxic and Targeted Therapies

Cancer patients experience kidney injury from multiple sources, including the tumor itself, diagnostic procedures, hypovolemia, infection, and drug exposure, superimposed upon baseline chronic damage. This review will focus on cytotoxic or targeted chemotherapy-associated renal injury. In this setting, tubulointerstitial injury and thrombotic microangiopathy (vascular injury) are more common than other forms of kidney injury including glomerular. Cisplatin, pemetrexed, and ifosfamide are well-known causes of acute tubular injury/necrosis. Acute interstitial nephritis seems underrecognized in this clinical setting. Interstitial nephritis is emerging as an "immune-related adverse effect" (irAE's) with immune checkpoint inhibitors in small numbers of patients. Acute kidney injury is rarely reported with targeted therapies such as BRAF inhibitors (vemurafinib, dabrafenib), ALK inhibitors (crizotinib), and mTOR inhibitors (everolimus, temsirolimus), but additional biopsy data are needed. Tyrosine kinase inhibitors and monoclonal antibodies that block the vascular endothelial growth factor pathway are most commonly associated with thrombotic microangiopathy. Other causes of thrombotic microangiopathy in the cancer patients include cytotoxic chemotherapies such as gemcitabine and mitomycin C, hematopoietic stem cell transplant, and cancer itself (usually high-stage adenocarcinoma with marrow and vascular invasion). Cancer patients are historically underbiopsied, but biopsy can reveal type, acuity, and chronicity of renal injury, and facilitate decisions concerning continuation of chemotherapy and/or initiation of renoprotective therapy. Biopsy may also reveal unrelated and unanticipated findings in need of treatment.

The renal effects of ALK inhibitors

Anaplastic lymphoma kinase 1 (ALK-1) is a member of the insulin receptor tyrosine kinase family. In clinical practice, three small molecule inhibitors of ALK-1 are used, namely crizotinib, ceritinib and alectinib. Several more agents are in active pre-clinical and clinical studies. Crizotinib is approved for the treatment of advanced ALK-positive non-small cell lung cancer (NSCLC). According to the package insert and published literature, treatment with crizotinib appears to be associated with kidney failure as well as an increased risk for the development and progression of renal cysts. In addition, this agent is associated with development of peripheral edema and rare electrolyte disorders. This review focuses on the adverse renal effects of Crizotinib in clinical practice.

Imaging features of renal complications after crizotinib treatment for non-small-cell lung cancer: a case report

Crizotinib has been approved for the treatment of advanced ALK-positive non–small cell lung cancer. Its use is associated with the development of complex renal cysts. However, there is limited literature regarding imaging features of renal cystic disease during crizotinib therapy and its complications or progression. Here, we describe a case of a patient with ALK-positive advanced non–small cell lung cancer who developed complex renal cyst during crizotinib treatment. The renal cyst is complicated by infection and abscess formation. Subsequent renal biopsy, antibiotics treatment, and open drainage of loculated renal abscess showed no malignant cells and contributed to the diagnosis. The imaging features should be recognized as renal cystic disease of crizotinib treatment and not to be mistaken as new metastasis and disease progression.

Second- and third-generation ALK inhibitors for non-small cell lung cancer

Crizotinib as the first-generation ALK inhibitor has shown significant activity in ALK-mutated non-small cell lung cancer (NSCLC). Second- and third-generation ALK inhibitors are entering clinical applications for ALK+ NSCLC. In addition, a third-generation ALK inhibitor, lorlatinib (PF-06463922), was reported to resensitize NSCLC to crizotinib. This review provided a summary of clinical development of alectinib, ceritinib, brigatinib (AP26113), and lorlatinib.

Chemotherapy-related complications in the kidneys and collecting system: an imaging perspective

Nephrotoxicity is a common adverse effect of many chemotherapeutic agents. The agents most commonly associated with chemotherapy-associated nephrotoxicity are methotrexate, semustine, streptozocin, mithramycin, and cisplatin. Certain chemotherapeutic agents have adverse effects on the kidneys and urothelium that can be visualized radiographically, including cystic change, interstitial nephritis, papillary necrosis, urothelial changes, haemorrhagic cystitis, acute tubular necrosis, and infarction. This review focuses on imaging features identifying complications of chemotherapy in the kidneys and collecting system and provides didactic cases to alert referring clinicians.

TEACHING POINTS

• Nephrotoxicity is a common adverse effect of many chemotherapeutic agents. • Chemotherapies have adverse renal and urothelial effects that can be visualized radiographically. • Crizotinib use can result in the development of complex renal cysts.