Optic neuropathy secondary to dasatinib in the treatment of a chronic myeloid leukemia case

Neuro-ophthalmic complications of modern anti-cancer drugs

PURPOSE

Targeted cancer therapies have been responsible for a dramatic shift in treatment strategies for cancer, and the number of drugs, classes, and indications are continually growing. Neuro-ophthalmic complications of these medications are an uncommon but important subset of adverse events which profoundly impact vision. This review aims to collate studies and reports of known neuro-ophthalmic complications of targeted therapies and describe their management.

METHODS

The anti-cancer drugs included in the review were any drugs targeting specific molecules involved in the cancer disease process. PubMed, EMBASE, and Web of Science were searched using the generic names of each drug and keywords of neuro-ophthalmic conditions. The prescribing information published by the US Food and Drug Administration (FDA) for each drug was also reviewed.

RESULTS

Several classes of targeted anti-cancer drugs were found to cause neuro-ophthalmic adverse effects. Immune checkpoint inhibitors are responsible for a raft of immune-related adverse events such as optic neuritis, ischemic optic neuropathy, PRES, and myasthenia gravis. Therapies with anti-VEGF activity can provoke posterior reversible leukoencephalopathy, which commonly presents with visual loss and can be fatal if not treated promptly. Inhibitors of BCR-ABL1, VEGF, ALK, and proteasomes have all been linked to optic nerve disorders which can have debilitating consequences for vision.

CONCLUSION

The neuro-ophthalmic complications of modern anti-cancer drugs can limit or necessitate the withdrawal of these life-prolonging medications. Ophthalmologists should be alert for neuro-ophthalmic complications in these medications to facilitate prompt diagnosis and treatment and reduce the risk of severe and permanent consequences.

Case report: First report of isolated central nervous system lymphoblastic crisis in a child with chronic myeloid leukemia on dasatinib therapy

Most children with chronic myeloid leukemia (CML) present with the chronic phase (CML-CP) at diagnosis, exhibiting an excellent treatment response to contemporary tyrosine kinase inhibitors (TKIs). However, despite TKI therapy, patients with CML-CP may progress to blastic crisis (BC). CML-BC rarely occurs in extramedullary sites, and isolated central nervous system (CNS) BC is an extremely rare condition. It may with present various neurologic symptoms that necessitates differential diagnosis from other causes such as TKI toxicity. Information on the diagnosis and treatment of this condition is lacking, as are well-established diagnostic criteria. Here, we report a case of isolated CNS lymphoblastic crisis in a child with CML-CP who was treated with dasatinib. The patient, an 8-year-old girl, was admitted owing to visual disturbance and severe headache. We highlight the importance of a CSF study for the differential diagnosis of CNS BC in patients with CML-CP who present with common neurologic symptoms during TKI therapy.

Adverse outcomes in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors: Follow-up of patients diagnosed 2002-2017 in a complete coverage and nationwide agnostic register study

Tyrosine kinase inhibitors (TKIs) have profoundly improved the clinical outcome for patients with chronic myeloid leukemia (CML), but their overall survival is still subnormal and the treatment is associated with adverse events. In a large cohort-study, we assessed the morbidity in 1328 Swedish CML chronic phase patients diagnosed 2002-2017 and treated with TKIs, as compared to that in carefully matched control individuals. Several Swedish patient registers with near-complete nationwide coverage were utilized for data acquisition. Median follow-up was 6 (IQR, 3-10) years with a total follow-up of 8510 person-years for the full cohort. Among 670 analyzed disease categories, the patient cohort showed a significantly increased risk in 142 while, strikingly, no category was more common in controls. Increased incidence rate ratios/IRR (95% CI) for more severe events among patients included acute myocardial infarction (AMI) 2.0 (1.5-2.6), heart failure 2.6 (2.2-3.2), pneumonia 2.8 (2.3-3.5), and unspecified sepsis 3.5 (2.6-4.7). When comparing patients on 2nd generation TKIs vs. imatinib in a within-cohort analysis, nilotinib generated elevated IRRs for AMI (2.9; 1.5-5.6) and chronic ischemic heart disease (2.2; 1.2-3.9), dasatinib for pleural effusion (11.6; 7.6-17.7) and infectious complications, for example, acute upper respiratory infections (3.0; 1.4-6.0). Our extensive real-world data reveal significant risk increases of severe morbidity in TKI-treated CML patients, as compared to matched controls, particularly for 2nd generation TKIs. Whether this increased morbidity may also translate into increased mortality, thus preventing CML patients to achieve a normalized overall survival, needs to be further explored.

Ocular Toxicity of Targeted Anticancer Agents

The proliferation of targeted anticancer agents over the last two decades has revolutionized cancer treatment and improved survival in many previously refractory malignancies. However, many agents are associated with characteristic ophthalmic adverse effects. It is important that ophthalmologists recognize and maintain a high index of suspicion for these side effects in patients on targeted therapy. Most ophthalmic adverse effects can be treated with specific ocular therapy without discontinuation of cancer treatment, although it is important to be aware of the life-threatening and vision-threatening circumstances that would require therapy cessation in conjunction with the patient's oncologist. This review aims to summarize the ophthalmic adverse effects of targeted and hormonal anticancer agents and briefly describe their management.

Targeted Cancer Therapy and Its Ophthalmic Side Effects: A Review

Targeted cancer therapy agents are the latest development in cancer therapeutics. Although the spectrum of their use continues to expand, ocular side effects are frequently encountered with the use of cancer therapeutics. This review describes the ocular side effects of targeted cancer therapy agents.

A lot of nerve

A 71-year-old woman with a history of acute lymphoblastic leukemia presented with unilateral optic disc edema. Laboratory evaluations for infectious, inflammatory, and neoplastic etiologies were negative. Magnetic resonance imaging of the orbits with and without contrast demonstrated enhancement and thickening of the right optic nerve with mild stranding of the intraconal fat. She underwent three large-volume lumbar punctures, all of which were negative for malignancy. An optic nerve biopsy was ultimately performed, demonstrating malignant cells on immunohistochemical staining. This case illustrates a rare case of biopsy-proven leukemic infiltration of the optic nerve head as the presenting sign of leukemic relapse despite a negative systemic workup. Leukemic infiltration should be considered in the differential diagnosis for cases of acquired disc edema, especially in patients with a past medical history of leukemia.

Vogt-Koyanagi-Harada disease like presentation in patients with chronic myeloid leukemia

Purpose

To report two rare cases of chronic myeloid leukemia (CML) on tyrosine kinase inhibitors presenting as bilateral serous retinal detachment and ocular inflammation, simulating Vogt-Koyanagi-Harada (VKH) disease.

Methods

Case series and review of literature.

Result

Two young patients (one male and one female) with CML on treatment with tyrosine kinase inhibitors (imatinib and dasatanib) under remission presented with bilateral sudden vision loss. One patient had bilateral multiple pockets of serous retinal fluid while the other had panuveitis with exudative retinal detachment. There was neither prodromal symptoms nor systemic signs and symptoms suggestive of VKH in both cases. They responded well to systemic steroid therapy without recurrences with complete visual recovery.

Conclusion and importance

CML patients can have features similar to VKH even during stable hematological phase and may be possibly associated with the use of tyrosine kinase inhibitors. Hence it is important not to misdiagnose and treat such patients with long term immunomodulators.

Neurological complications of new chemotherapy agents

This last decade has yielded more robust development of cancer treatments and first-in-class agents than ever before. Since 2006, nearly one hundred new drugs have received regulatory approval for the treatment of hematological and solid organ neoplasms. Moreover, older conventional therapies have received approval for new clinical indications and are being used in combination with these newer small-molecule targeted treatments. The nervous system is vulnerable to many of the traditional cancer therapies, manifesting both already well-described acute and chronic toxicities. However, newer agents may produce toxicities that may seem indistinguishable from the underlying cancer. Early recognition of neurotoxicities from new therapeutics is vital to avoid irreversible neurological injury. This review focuses on cancer therapies in use in the last 10 years and approved by the FDA from January 2006 through January 1, 2017.

Clinical Pharmacokinetics and Pharmacodynamics of Bosutinib

Chronic myeloid leukemia (CML) is a clonal myeloproliferative stem cell disorder. Bosutinib is an oral, once-daily SRC/ABL tyrosine kinase inhibitor with very potent inhibitory activity. Bosutinib is effective against all phases of intolerant or resistant Philadelphia chromosome-positive CML that do not harbor the T315I or V299LABL kinase domain mutations. Peak plasma concentrations of bosutinib occur at 4-6 h following oral administration, and dose-proportional increases in exposure are observed at doses ranging from 200 to 800 mg. Absorption of bosutinib increases with food. Bosutinib is distributed extensively into the tissues. It is highly plasma protein bound (94 %) and is primarily metabolized in the liver by cytochrome P450 3A4. Bosutinib is well tolerated overall and has a unique but manageable toxicity profile. This article provides a review of the available clinical pharmacokinetic, pharmacodynamic, and drug-drug interaction data on bosutinib in healthy subjects, patients with CML, and special populations.

Optic neuropathy in the context of leukemia or lymphoma: diagnostic approach to a neuro-oncologic emergency

Background

Optic neuropathy in the context of leukemia or lymphoma has a broad differential diagnosis, including infiltration, infection, inflammation, compression, and medication effects. Confirming the underlying etiology in a timely manner is crucial as, while infiltration carries a poor prognosis, treatment modalities can have serious consequences themselves.

Methods

A review of the literature was conducted for cases of isolated optic neuropathy in the context of leukemia or lymphoma, in which the underlying etiology remained unclear following initial clinical examination and neuroimaging. Clinical, radiological, and pathological characteristics of the cases are summarized.

Results

Ninety-two cases meeting inclusion criteria were identified. Leukemic or lymphomatous infiltration was the presumed diagnosis in 72% of the reports, indicating this is the most likely etiology in such cases. The remaining reports were attributed to inflammation, infection, or drug toxicity. For illustrative purposes, the previously unpublished case of an 11-year-old girl with remitted T lymphoblastic lymphoma is presented. She suffered recurrence in the form of isolated left optic nerve infiltration that required transconjunctival biopsy to confirm diagnosis.

Conclusions

Optic nerve infiltration by leukemia or lymphoma requires both diagnostic certainty and urgent management. Recommendations are made for a step-wise, yet rapid investigative approach that may ultimately require biopsy of the optic nerve.