[Local treatment of choroidal melanoma: possibilities and limitations]

[Predicting the effectiveness of organ-preserving treatment of choroidal melanoma using optical coherence tomography data]

Optical coherence tomography (OCT) is currently widely used for the diagnosis of choroidal melanoma (CM), but the problem of predicting the outcomes of planned CM treatment remains unsolved.

PURPOSE

This study was conducted to identify OCT signs that adversely affect the outcome of organ-preserving CM treatment.

MATERIAL AND METHODS

OCT scan images of 30 patients who underwent organ-preserving treatment and were under observation were selected for this study. Brachytherapy (BT) as monotherapy was performed in 27 patients (in 2 cases - twice, and in 1 case - three times), in one patient - in combination with the previous transpupillary thermotherapy (TTT). Multiple TTT (4 sessions within 4 months) as monotherapy were performed in 2 patients. In 9 cases, a single organ-preserving treatment (BT - 6 patients, TTT - 3 patients) was ineffective. In these cases, the effectiveness of the first stage of organ-preserving treatment was taken into account.

RESULTS

Seven signs of an unfavorable prognosis of the performed treatment were identified by analyzis of tomograms and statistical processing of the obtained data. These signs include: the presence of intraretinal edema, detachment of the neuroepithelium (NED) over the tumor, including with a break in the photoreceptors, accumulation of transudate over the tumor, the presence of large cysts, intraretinal cavities and NED near the tumor (secondary retinal detachment). A combination of three or more signs were observed in all cases of inefficiency of the first stage of treatment. Most often, intraretinal edema and NED over the tumor were combined with the accumulation of subretinal transudate and NED near the tumor. The presence of 6 or all 7 signs took place in cases of a negative therapeutic effect after local destruction.

CONCLUSION

When planning organ-preserving CM treatment, in addition to biometric parameters, it is necessary to pay special attention to the identification of such morphological signs as NED over and near the tumor, accumulation of transudate under the NED, the presence of intraretinal edema, large intraretinal cysts and cavities.

[Epigenetic markers of choroidal melanoma]

MicroRNAs (miRNAs) are short non-coding RNAs (18-25 nucleotides in length) that are important participants in the regulation of gene expression. In 2003, their active role in oncogenesis was demonstrated. In 2008, the first report on the isolation of miRNAs from uveal melanoma (UM) tissue was published. Four years later (2012), the presence of miRNAs in the plasma of patients with this category was shown. To date, changes in the expression level of 100 miRNAs in the plasma of cancer patients (with cancer of various localizations) out of the 2654 miRNAs described in mirbase.org have been proven. In the plasma of patients with UM, changes in the expression of only 13 miRNAs have been confirmed. As a rule, studies were conducted in patients at the stage of hematogenous metastasis of UM.

PURPOSE

This study analyzed the expression pattern of miRNA-223 and miRNA-126 in patients with localized choroidal melanoma (CM) taking into account biometric parameters in the absence of metastases.

MATERIAL AND METHODS

Blood plasma of 84 patients with M0N0 CM aged 35-86 years (mean age 63.4±1.2 years) was investigated. The basis for the diagnosis of CM was the results of ophthalmological examination, optical coherence tomography, and ultrasound scanning. In all cases, the absence of metastases was proven (using computed tomography or magnetic resonance imaging). Control - plasma of 28 volunteers (mean age 62.9±1.42 years, age range 45-78 years), who did not have tumoral, autoimmune, or chronic inflammatory processes. The expression levels of miRNAs circulating in blood plasma were determined by real-time polymerase chain reaction.

RESULTS

An increase in the expression levels of miRNA-223 and miRNA-126 in the plasma of all 84 patients with CM was confirmed compared to the control group. Features of the miRNA expression pattern that emerged with changes in the tumor's quantitative parameters were identified.

CONCLUSION

Evaluation of the levels of miRNA-223 and miRNA-126 in the blood plasma of patients with CM can be used in clinical practice to clarify the diagnosis of CM, as well as to predict the development of hematogenous metastases.

Stereotactic irradiation on linear accelerator - ultrasound versus MRI in choroidal melanoma volume calculation

Background

Stereotactic irradiation is one of the treatment modalities for intraocular uveal melanoma. The study’s purpose was to describe the background of stereotactic one-day session radiosurgery, how the comparison in the difference between the tumor volume measured values from the magnetic resonance imaging (MRI) method and the ultrasound method was related to it, and which method was more precise to be used for tumor regression after irradiation.

Methods

The group of 147 patients with choroidal melanoma was treated by stereotactic irradiation on the linear accelerator with a single dose of 35.0 Gy. During the standard treatment process the uveal melanoma volumes, needed for dose calculation, were obtained using MRI from the individual stereotactic planning scheme and by ultrasound from the ultrasound device. All volumes were statistically compared using the paired t-test, and for the visualization purpose, the Bland-Altman plot was used.

Results

In the group of patients, it was 70 (47.6%) males and 77 (52.4%) females. The tumor volume median was from MRI equal to 0.44 cm³ and from ultrasound equal to 0.53 cm³. The difference between the ultrasound and the MRI volume measured values was statistically significant. However, the Bland-Altman plot clearly documents that the two methods are in agreement and can be used interchangeably. In most of the cases, the measured values of the ultrasound-calculated volume achieved slightly higher measured values.

Conclusions

The calculation of the intraocular uveal tumor volume is a crucial part of the stereotactic irradiation treatment. The ultrasound volume measured values were in most of the cases higher than the measured values from the MRI. Although the methods are comparable and can be used interchangeably, we are recommending using the more precise MRI method not only during the treatment but also on later regular medical checks of tumor regression or progression.

Two 11-Years Periods Statistics and Trends of Enucleation and Evisceration

Purpose:

The indications for evisceration and enucleation are still evolving and controversial. The study aims to describe trends of enucleation versus evisceration in one center.

Methods:

In period 1998–2019 were 353 patients were included in the study. Statistical results and Chi-square test for pair-wise comparisons for the statistical significance in comparing two subgroups (years periods 1998–2008 and 2009–2019) per category have been evaluated.

Results:

The enucleation was performed in 306 patients, and the evisceration was performed in 47 patients. In 221 patients with the tumor exclusively enucleation was indicated. For the operation technique, the authors got a chi-square value of 0.027, and the associated P value is at 0.8695, then the number of evisceration and enucleation in subgroups have not confirmed independency. For the tumor presence, the authors got a chi-square value of 5.4, and the associated P value is at 0.02, then the number of validated/nonvalidated tumor presence in subgroups confirmed independency.

Conclusions:

The performed enucleations had 98% cases uveal melanoma, 1% of cases of another type of malignancy (lymphoma non-Hodgkin type), and 1% cases with benign tumor. Enucleation is also today most frequently due to malignant intraocular tumors, whereas evisceration if most frequently for the phthisis eye after a trauma or a previous intraocular surgery. In our study in 22 years interval also in the second period, there was an increased trend of enucleation due to intraocular malignancy. It can have many reasons, especially, that patients are sent to oncology centers late in the advanced stage of tumor.

Importance of PET/CT examination in patients with malignant uveal melanoma

INTRODUCTION

Diagnostic and therapeutic management of the patient with malignant uveal melanoma (MMU) is subject to ongoing efforts to innovate. PET/CT (Positron Emission Tomography / Computed Tomography) examination is important in both diagnosis and metastases.

MATERIAL AND METHODS

Evaluation of the importance of PET/CT examination in the group of patients diagnosed with MMU in the period 12.1.2016 to 6.12.2018. All patients with a diagnosis of secondary retinal detachment, suspected uveal melanoma, underwent standard examinations to detect possible metastases (liver ultrasound, chest X-ray). Patients for whom a stereotactic radiosurgery solution was planned due to the stage of the disease this examination was to exclude metastasis in the liver or lungs. PET/CT examination is part of the protocol within the exclusion criteria for treatment with stereotactic radiosurgery in one day session surgery.

RESULTS

In the group of 84 patients, 47 women (56 %) and 37 men (44 %) were aged between 26 and 90 years. Their average age was 61.4 years. The median group was 64 years, modus 65 years. Of 84 patients, 79 (94 % of cases) had a diagnosis of C69.3 (choroidal melanoma) and 5 patients (6 % of cases) had a diagnosis of C69.4 (ciliary body melanoma). Subsequent PET/CT examination in many patients did not reveal hypermetabolic manifestations that could involve various pathological processes, in others the radiopharmaceutical was captured in the primary tumor area of the uveal tract. Hypermetabolism in eye globe was only found in melanomas with a volume of more than 0.5 cm3. PET/CT examinations were 85, with one patient undergoing examination twice. However, in 25 patients (26 examinations), the radiopharmaceutical was taken up in places that subsequently required closer attention. The initial aim of the examination was to locate possible metastases of MMU. In the others, 3 incidents have been reported: increased metabolism in the lung and liver, thyroid and mediastinal lymph nodes. Of the 85 examinations, 26 (30.6 %) resulted in a hypermetabolic manifestation of accumulation, which was not located in the eye tract, resp. right in the eye. Two malignancies (prostatic carcinoma and rectosigmal carcinoma) have occurred in two patients. Very important was the discovery of MMU metastasis in the liver, which confirmed the important role of PET/CT examination in the management of MMU patients. The metastasis was discovered after repeated PET/CT examination.

CONCLUSION

PET/CT examination is a technically demanding examination and is one of the possibilities of imaging intraocular melanoma in tumors with volume more than 0.5 cm3. It is important in determining the grading and staging of the disease before radiosurgical treatment and also in detecting possible metastases after MMU treatment in cases where ultrasound or MRI examinations do not give a definite result. However, our study confirmed the significance of this examination for randomly detected 2 duplex malignancies (2.4%) and 3 incidentalomas (3.6%) in patients whose ophthalmologist diagnosed uveal melanoma and sent patients for full-body PET/CT examination.

Uveal melanoma

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. UMs are usually initiated by a mutation in GNAQ or GNA11, unlike cutaneous melanomas, which usually harbour a BRAF or NRAS mutation. The annual incidence in Europe and the USA is ~6 per million population per year. Risk factors include fair skin, light-coloured eyes, congenital ocular melanocytosis, ocular melanocytoma and the BAP1-tumour predisposition syndrome. Ocular treatment aims at preserving the eye and useful vision and, if possible, preventing metastases. Enucleation has largely been superseded by various forms of radiotherapy, phototherapy and local tumour resection, often administered in combination. Ocular outcomes are best with small tumours not extending close to the optic disc and/or fovea. Almost 50% of patients develop metastatic disease, which usually involves the liver, and is usually fatal within 1 year. Although UM metastases are less responsive than cutaneous melanoma to chemotherapy or immune checkpoint inhibitors, encouraging results have been reported with partial hepatectomy for solitary metastases, with percutaneous hepatic perfusion with melphalan or with tebentafusp. Better insight into tumour immunology and metabolism may lead to new treatments.