Tapioca melanomas of the iris: immunohistology and report on two cases

Case Report: Tapioca Iris Melanoma: An Uncommon Presentation of an Uncommon Tumor

SIGNIFICANCE

Iris tumors are rare conditions, and there is a relative paucity of recent published data on its broad clinical spectrum. Tapioca iris melanoma is a rarer yet devastating form with wide and challenging differential diagnoses because of its amelanotic nodular appearance.

PURPOSE

This study aimed to report the challenging presentation of an uncommon iris melanoma, describing the clinical and histological findings and comparing them with the existing published data.

CASE REPORT

An uncommon clinicopathological report on the tumor unusual localization, patient age, absence of elevated IOP and heterochromia, and negative S-100 stain that caused diagnostic uncertainty is presented. The patient remains free of metastatic disease 7 years after a complete tumor full-thickness excision.

CONCLUSIONS

Tapioca iris melanomas are uncommon tumors with a presentation/surgical management that differs from other malignant tumors. Ophthalmologists should consider it among the vast differential diagnoses when observing amelanotic lesions, even without the hallmark signs being evident.

Tapioca Melanoma of the Iris: A Case Report

Purpose

To report an extremely rare case of tapioca melanoma of the iris in an Iranian patient.

Case Report

A 50-year-old male patient presented with ocular pain and redness in the right eye for two weeks. The visual acuity was 7/10 and the intraocular pressure (IOP) was 30 mmHg. A lobulated amelanotic vascularized and nodular (tapioca-like) iris mass with a 180o extent was seen in the right eye. Incisional biopsy of the mass revealed atypical mixed type (epithelioid and spindle cell) melanoma. Brachytherapy with the ruthenium-106 plaque resulted in complete regression of the tumor.

Conclusion

Tapioca melanoma of the iris should be considered in the differential diagnosis of patients presenting with nodular vascularized amelanotic iris mass and elevated IOP. Brachytherapy with ruthenium-106 seems to be an effective treatment for tapioca melanoma of the iris.

Proton beam therapy for presumed and confirmed iris melanomas: a review of 36 cases

BACKGROUND

To report the clinical features and outcomes of iris melanomas treated by proton beam therapy.

MATERIALS AND METHODS

A retrospective study was conducted at the Croix-Rousse University Hospital of Lyon, Department of Ophthalmology, in 36 patients treated by proton beam therapy for presumed (n = 29) and confirmed (n = 7) iris melanomas between July 1997 and October 2010. Ciliary body melanomas with iris involvement were excluded. The patients' mean age was 54.4 years (range, 22-82 years). The average tumor diameter was 3.8 mm (range, 2.5-8.0). The iridocorneal angle was invaded by the tumor in 47% of cases (n = 17), the ciliary body in 17% of cases (n = 6), and the sclera in 3% (n = 1). Raised intraocular pressure was present before treatment in 11.1 % of cases (n = 4). Tumor biopsy was performed in 19% of cases (n = 7). Four patients had undergone an initial incomplete surgical excision of tumor before radiotherapy. Surgical preparation of the eye with tantalum ring positioning had been performed in all cases 3-4 weeks before irradiation. The prescribed dose was 60 Cobalt Gray Equivalent (CGE) of proton beam radiotherapy delivered in four fractions on four consecutive days.

RESULTS

The median follow-up was 50 months (mean 60.5, range 15-136). One patient (2.7%) was lost to follow-up. None of the patients showed tumor progression, local recurrence, or metastasis. None of the patients required secondary enucleation. Cataract was developed in 62% of patients, glaucoma in two cases (6%) after irradiation, and hyphema with the aggravation of pre-existing glaucoma in one patient. No patients developed neovascular glaucoma.

CONCLUSIONS

Proton beam therapy appears to be the treatment of choice for the conservative treatment of iris melanomas with excellent tumor control and an acceptable rate of complications. Longer follow-up studies on a larger series is necessary to consolidate these results.

Tapioca melanoma of the iris without iris heterochromia

PURPOSE

A case of a teenage girl with tapioca melanoma of the iris is presented. This case is unusual, as the patient did not have heterochromia and did not present with elevated intraocular pressure.

CASE REPORT

A 14-year-old female patient presented with an amelanotic, multinodular, multifocal lesion of the right iris. Pathology confirmed a diagnosis of tapioca melanoma using immunohistologic staining. The patient underwent enucleation of her right eye and has been free of metastatic disease 3 years later.

CONCLUSIONS

Tapioca melanoma of the iris must be included among the other differential diagnoses when examining patients with amelanotic iris lesions, even when iris heterochromia is not clearly evident.

En bloc excision of intraocular epithelial cystic downgrowth using syngeneic auricular cartilage

AIM

To describe the surgical management of epithelial cystic downgrowth by en bloc excision and use of syngeneic auricular cartilage in two children.

STUDY DESIGN

Retrospective interventional case series.

METHOD

The charts of two patients treated for epithelial cystic downgrowth with en bloc excision and auricular cartilage transplant were reviewed. Details of ocular history, preoperative and postoperative visual acuity, intraocular pressure, ocular examination findings, surgical procedure and subsequent management were noted.

RESULTS

Two children aged 4 and 6 years, with epithelial cysts who underwent en bloc excision were identified. The cysts had developed following penetrating eye injury. Surgery involved en bloc resection of the cyst and associated tissue, and replacement of the excised corneoscleral tissue with syngeneic auricular cartilage. One patient additionally required synechiolysis, discission of a secondary cataract and anterior vitrectomy. In both cases, the epithelial tissue was successfully removed and the auricular cartilage transplant was well-apposed. Visual acuity remained at the preoperative level in the first patient due to amblyopia; in the second patient visual acuity improved to 6/7.5 with mild astigmatic correction.

CONCLUSION

En bloc excision provides the most definitive surgical treatment of cystic epithelial downgrowth. Auricular cartilage may be used for sclerokeratoplasty when donor cornea or sclera is unavailable.

Tapioca melanoma of the iris mimicking a vascular tumour: a clinicopathological correlation

Although vascular iris processes are usually benign, they may be a clinical manifestation of iris melanoma, and this should be considered in the differential diagnosis. The case is reported of a 20-year-old man with a highly vascularized tapioca melanoma of the left iris without involvement of the anterior chamber angle or ciliary body, but with observed growth tendency. Sector iridectomy was performed 2 months after first examination. In addition, two separate floating tumour nodules were observed in the anterior chamber angle at 6 o'clock and were removed by aspiration. After 1 year follow up, no recurrence of melanoma cells was observed. In tapioca iris melanomas, diagnostic differentiation from congenital, inflammatory, vascular and neoplastic iris processes is required. Careful biomicroscopic examination of the iris in patients with vascular iris tumours may help the ophthalmologist to identify malignant iris melanomas (tapioca type) and plan appropriate surgical treatment.