Regression of taxane-related cystoid macular edema after topical dorzolamide treatment: two case reports

Abstract

Background: Cystoid macular edema is a rare, vision-threatening side effect of the taxane family of anticancer agents. There is no established treatment or standard treatment protocol for taxane-related cystoid macular edema. Here, we report two cases of taxane-related cystoid macular edema that were treated with topical dorzolamide.

Case presentation: In case 1, a 72-year-old Japanese woman with bilateral geographic choroiditis reported for a follow-up visit with a complaint of blurred vision in both eyes for 2 months after starting nanoparticle albumin-bound paclitaxel chemotherapy for multiple metastases of her breast cancer. Her best-corrected visual acuity had dropped from 1.2 to 0.9 in the right eye and from 1.0 to 0.4 in the left eye. Fundus examination showed no newly active geographic choroiditis lesion, but optical coherence tomography exhibited cystoid macular edema. We suspected taxane-related cystoid macular edema and terminated nanoparticle albumin-bound paclitaxel, and started topical dorzolamide treatment. Cystoid macular edema nearly resolved within 6 weeks in the right eye and within 10 weeks in the left eye after starting topical dorzolamide treatment. The resolution of cystoid macular edema without leaving a chorioretinal scar after discontinuation of paclitaxel confirmed our initial diagnosis of taxane-related cystoid macular edema. A few inconspicuous cystoid spaces persisted at the parafovea for a year after dorzolamide treatment ended, but regressed after restarting dorzolamide treatment without any side effects. Best-corrected visual acuity improved to 1.2 in the right eye and 1.0 in the left eye. In case 2, a 70-year-old Japanese man, who received nanoparticle albumin-bound paclitaxel for pancreatic cancer with multiple metastases, developed bilateral cystoid macular edema. Best-corrected visual acuity was 0.3 bilaterally. Cystoid macular edema resolved within 5 weeks after stopping nanoparticle albumin-bound paclitaxel and starting topical dorzolamide treatment confirming the diagnosis of taxane-related cystoid macular edema. Nine weeks later, best-corrected visual acuity improved to 0.8 in the right eye and 1.0 in the left eye.

Conclusions: Cystoid macular edema in each case resolved within a few months without any side effects using topical dorzolamide and terminating taxane-based chemotherapy. Topical dorzolamide appears to be a safe and effective treatment option for patients with taxane-related cystoid macular edema whose quality of life is threatened by visual disturbances.

Keywords: Cystoid macular edema; Dorzolamide; Nab-paclitaxel; Optical coherence tomography; Taxane.

Fig. 1.

Fundus photographs and optical coherence tomography (OCT) images of case 1 before and after starting nanoparticle albumin-bound paclitaxel (nab-PTX) treatment. A, B Upper images are fundus photographs. Lower images are 8-mm B scan OCT (RTVue XR Avanti, Optovue, Fremont, CA) images. White arrows in the fundus photographs indicate scanning lines of the OCT shown below those. A Images of the right and left eye prior to starting nab-PTX treatment. Fundus photographs show chorioretinal scars from geographic choroiditis. OCT images show scars in the outer retina and choroid. No obvious cystoid macular edema (CME) is observed. B Images following three cycles of nab-PTX treatment, 2 weeks after the last treatment. Fundus photographs show no obvious change as compared with pretreatment photographs in (A). OCT images show bilateral CME with cystoid spaces located in the inner and outer nuclear layers

Fig. 2.

Clinical course of case 1. A Changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT) are shown, in addition to the administration period of nanoparticle albumin-bound paclitaxel (nab-PTX) and topical dorzolamide. The numbers on the horizontal line show weeks since topical dorzolamide first started. Time points of each OCT images taken are indicated by arrows. B–D Optical coherence tomography (OCT) images before and after topical dorzolamide treatment. A 6-mm horizontal sectional OCT scan (A: DRI OCT Triton, Topcon, Tokyo, Japan; B and C: RTVue XR Avanti, Optovue, Fremont, CA). Upper images are of the right eye and lower images are of the left eye. B OCT image when dorzolamide treatment was started, 3 weeks after the first visit for blurred vision and 5 weeks after the last nab-PTX treatment. Cystoid macular edema (CME) is observed bilaterally. C Six weeks after topical dorzolamide treatment was started. While CME is almost resolved and the foveal depression is restored in the right eye, CME is still observed in the left eye. D Ten weeks after topical dorzolamide was started. Foveal depression is restored bilaterally, and few cystoid spaces are observed

Fig. 3.

Optical coherence tomography (OCT) images of the left eye in case 1, before and after restarting topical dorzolamide. A, B, and C Upper images are 3 × 3 mm deep layer en face OCT scans. Middle images are 3-mm horizontal sectional scans with segmentation lines for the upper en face OCT images. Lower images are 8-mm horizontal sectional scans across the fovea (RTVue XR Avanti, Optovue, Fremont, CA). White arrows indicate cystoid spaces in the retina. A Four months after topical dorzolamide treatment ended. While en face OCT reveals cystoid spaces in the retina, few cystoid spaces can be observed with the B-scan across the fovea. B One year after topical dorzolamide ended. Persistent cystoid spaces are observed in the en face OCT. Small cystoid spaces are also observed in the B-scan across the fovea. C Three months after topical dorzolamide was resumed. Regression of cystoid spaces is observed with en face OCT and B-scan

Fig. 4.

Fundus photographs in case 2, 3 weeks after the last dose of nanoparticle albumin-bound paclitaxel. No findings suggestive of vascular diseases or uveitis are observed in either fundus

Fig. 5.

Optical coherence tomography (OCT) images in case 2 before and after topical dorzolamide treatment. A A 6-mm and B 9-mm horizontal sectional scan OCT (DRI OCT Triton, Topcon, Tokyo, Japan). A Three weeks after the last dose of nanoparticle albumin-bound paclitaxel treatment. OCT shows prominent cystoid macular edema (CME) in both eyes. Focal choroidal excavation is observed at the left fovea. B Five weeks after topical dorzolamide treatment was started. No CME is observed