[Orbital mantle cell lymphoma succesfully treated by Bcl-2 inhibitor: Report of a case]

Lymphoma is the most common orbital malignancy in adults. Among the types of lymphoma, mantle cell lymphoma is a particularly aggressive form, often discovered through systemic involvement, with a dismal prognosis due to frequent recurrences. It is secondary to a t (11 ; 14) (q13; q32) chromosomal translocation resulting in an anti-apoptotic signal via overexpression of Bcl-2. Treatment is based on R-CHOP poly-chemotherapy. We describe the case of a patient with an orbital recurrence of mantle cell lymphoma successfully treated with oral Bcl-2 inhibitor monotherapy. A 58-year-old man who was treated with R-CHOP 8 years ago for mantle cell lymphoma, in remission for 5 years, presented with progressive decreased visual acuity in the left eye, along with binocular diplopia. Clinical examination revealed a decrease in visual acuity in the left eye to 1/20 Parinaud 20 and a relative afferent pupillary defect on the left. External examination revealed a left cranial nerve VI palsy, 2mm of painless proptosis, and hypesthesia of the left V1 territory, leading to a diagnosis of left orbital apex syndrome. The disc and macular OCT were normal. The visual field showed enlargement of the left blind spot. An emergency CT scan and MRI revealed an apical extraconal tissue mass infiltrating the medial rectus muscle, extending to the superior orbital fissure, optic canal and left cavernous sinus, hyperintense on T2 weighted images and isointense on T1. The morphological appearance was strongly suggestive of an infiltrative lymphomatous process. An 18 FDG PET-scan identified the orbital lesion as well as enhancing lesions in the axilla and colon; given the clinical features and test results, the diagnosis of recurrent mantle cell lymphoma was made without biopsy. Treatment with Venetoclax (Bcl-2 inhibitor) was initiated. At one month of treatment, the orbital apex syndrome had entirely resolved, with visual acuity increased to 8/10 Parinaud 4 and a metabolic return to normal on PET scan. The PET scanner and clinical examination at 3 months were entirely normal. At the one-year follow-up visit, the patient was still on Venetoclax, the clinical examination was unchanged, and the PET-scan still showed a complete metabolic response.

[Rationale for a diagnostic approach in non-Graves' orbital inflammation--Report of 61 patients]

INTRODUCTION

Orbital inflammatory syndromes include a wide variety of inflammatory intraorbital processes which are very different in terms of clinical presentation and prognosis. We currently prefer to differentiate so-called "specific" inflammations, for which an etiology is able to be identified, from idiopathic orbital inflammatory syndromes (IOIS), for which the etiology remains unknown and the histology is nonspecific.

PURPOSE

To propose an efficient diagnostic approach for clinicians managing patients with non-Graves' orbital inflammations.

MATERIALS AND METHODS

This is a retrospective and prospective study concerning 61 patients managed by the medical team for non-Graves' orbital inflammations between May, 1999 and May, 2013 in the ophthalmology departments of Nice and Limoges university hospitals in France. Seventeen specific inflammations, 19 orbital lymphomas and 25 idiopathic orbital inflammatory syndromes were included. Patients were divided into two groups. Thirty-six patients (group 1) underwent primary biopsy, while for the other 25 (group 2), therapy was begun empirically without biopsy. We could therefore compare both approaches in terms of diagnostic efficiency and time until identification of a specific etiology.

RESULTS

Our statistical results show that an approach without primary biopsy leads to a number of specific diagnoses statistically much lower than that obtained by the approach with primary biopsy. Also, the risk of missing a specific inflammation (with as a consequence an inappropriate treatment and a risk of functional sequelae as well as a fatal risk of missing a lymphoproliferative pathology) is very clearly higher in the case of not performing primary biopsy. Finally, the average time elapsed between the initial consultation with the ophthalmologist and a specific diagnosis was one month in the case of the first approach, while this delay was almost three times higher with the second approach, with a mean of 2.91 months (P<0.01).

DISCUSSION

Our study shows that biopsy should be the mainstay of diagnostic management. A trial of empiric treatment is only performed first in myositis or in locations where biopsy could jeopardize functional prognosis. It should only be done after biopsy in all other cases. Of course, in all cases of relapse or recurrence after treatment, biopsy should be performed or repeated.

CONCLUSION

The diagnostic work-up of a patient with an orbital inflammatory process must of course include blood testing and orbital imaging, but also a systematic primary biopsy for histological examination in the vast majority of cases. It must be repeated at least in the case of any doubt about the diagnosis or in the case of any recurrence or resistance to treatment.