Foveal cone loss in tamoxifen maculopathy: a case report

BACKGROUND

Tamoxifen is used in low dose concentrations (20-40 mg per day) as a therapy for breast cancer but is known to have ocular side effects. In this case report, the foveal cone integrity in a tamoxifen-treated patient who complained of a small central scotoma in the left eye while reading was examined using high resolution adaptive optics imaging.

CASE PRESENTATION

Both eyes of a 54-year-old Caucasian, non-hispanic female who had been treated with tamoxifen for 1.5 years were examined using various imaging modalities including fundus photography, fundus autofluorescence, fluorescein angiography, spectral-domain optical coherence tomography, and adaptive optics scanning laser ophthalmoscopy. Clinical spectral-domain optical coherence tomography showed a very small disruption to the photoreceptor layer at the fovea in the left eye only. However, adaptive optics scanning laser ophthalmoscopy imaging revealed foveal cone loss in both eyes, but to a lesser extent in the right eye. Inner retinal changes were not observed in either eye.

CONCLUSION

The area of cone loss was similar in size to a single newsprint letter when projected onto the retina, matching the patient's description of a scotoma in the left eye. Given the isolated loss of foveal cone photoreceptors with the absence of previously reported inner retinal and vascular changes, our results may indicate the earliest retinal changes associated with tamoxifen retinopathy.

Tamoxifen induced maculopathy presenting like macular telangiectasia type 2 in a patient with breast cancer

INTRODUCTION

Drug-induced crystalline maculopathy has been reported secondary to tamoxifen use for breast cancer treatment. It could be misdiagnosed as macular telangiectasia type 2 (MacTel type 2).

CASE REPORT

A 56-year-old woman with a history of diabetes mellitus and breast cancer was referred to our clinic with painless, bilateral, gradual onset of central vision loss for several months. The fundus examination showed the macular pigmentary change in both eyes and a few refractile crystalline deposits in the parafoveal area in the left eye. However, the rest of the retina was normal in both eyes.

MANAGEMENT AND OUTCOME

With the diagnosis of tamoxifen-induced maculopathy, the drug was discontinued and supplementary treatment was started.

DISCUSSION

In this report, patient medical and drug history was an important and powerful measure. Due to the side effects of long-term use of tamoxifen, we need further studies on the need for retinal screening in these patients.

Tamoxifen maculopathy: The importance of screening and long follow-up

We report a case of a patient treated with tamoxifen 20mg daily as hormone therapy for breast cancer. On regular ophthalmological follow-up, tamoxifen maculopathy was detected on SD-OCT (Spectral Domain Optic Coherence Tomography, Carl Zeiss Meditec®), so the medication was discontinued. Despite discontinuation of the medication, the maculopathy progressed over time. We have been following our patient for seven years. Tamoxifen may produce a toxic maculopathy which may progress despite discontinuation of the medication. We consider our case interesting, given the lengthy follow-up of the patient with sequential SD-OCT images. To the best of our knowledge, our case represents the longest follow-up period for a patient with tamoxifen maculopathy. Moreover, we would like to stress the importance of screening in asymptomatic patients on this medication, in order to detect early pathological signs.