Clinicopathologic findings in choroidal melanomas after failed transpupillary thermotherapy

Long-term Outcomes of Small Pigmented Choroidal Melanoma Treated with Primary Photodynamic Therapy

PURPOSE

To report the long-term outcomes of patients with small, pigmented, posteriorly located choroidal melanoma undergoing primary treatment using photodynamic therapy (PDT) with verteporfin at the London Ocular Oncology Service.

DESIGN

Retrospective, interventional, consecutive case series.

PARTICIPANTS

All patients undergoing primary treatment using PDT with verteporfin from April 2014 to December 2015 and followed until December 2019.

METHODS

This is a long-term follow-up study of the same cohort of patients previously reported by our group in 2017 and 2018.

MAIN OUTCOME MEASURES

Local tumor control, visual outcomes, and metastasis-free survival.

RESULTS

Twenty-six patients were included with a mean (± standard deviation) age and tumor thickness of 62 ± 14 years and 1.3 ± 0.5 mm, respectively. Tumors were posteriorly located (mean distance to optic nerve and fovea = 2.0 ± 2.2 mm and 1.6 ± 1.5 mm, respectively), and the majority were fully pigmented (73%). Overall, patients were followed for a median (interquartile range [IQR], range) of 49.5 (15.3, 7.0-66.0) months from first PDT to last follow-up. Over the course of this study, 14 of 26 (54%) have developed a local recurrence at a median of 20.0 months (20.5, 4.7-60.9 months). The most common pattern of recurrence was an isolated increase in basal dimensions (9/14; 64%). Median (IQR) final logarithm of the minimum angle of resolution visual acuity of the whole cohort was 0.2 (0.5). The only statistically significant difference in baseline and outcome characteristics between treatment failures and nonfailures was the distance to the fovea (median [IQR], 0.5 [1.3] vs. 2.5 [2.8]; P = 0.002) and final logarithm of the minimum angle of resolution visual acuity (median [IQR], 0.50 [0.80] vs. 0.00 [0.14]; P = 0.002), respectively.

CONCLUSIONS

Although treatment of small pigmented posterior choroidal melanoma with PDT effectively preserves visual acuity, 5-year treatment-success calculated by Kaplan-Meier analysis was only 38.4%. Recurrences after PDT tend to occur along the tumor edges, often with minimal increase in thickness. Given the substantial risk of treatment failure, primary PDT with vertepofrin is recommended in exceptional cases of choroidal melanoma, for which other treatments with greater tumor control are not a feasible option.

Tumor Infiltrating Lymphocytes in Uveal Melanoma: A Link with Clinical Behavior?

Experimental and clinical evidence indicate that immunological mechanisms might be important in the clinical course of uveal malignant melanoma (UMM). We analyzed the amount and phenotype of tumor infiltrating lymphocytes (TIL) and the expression of the apoptosis-inducing molecule Fas and its ligand, FasL, on tumor cells and TIL in a selected series of UMM with the aim to establish if a correlation between their expression and the clinical behavior of UMM exists. TIL phenotype and Fas/FasL expression were evaluated by immunohistochemistry in 61 cases of formalin-fixed, paraffin-embedded UMM. Results were compared with the follow-up data of patients. Most of the UMM showed a prevalence of CD8+ CD3+ T lymphocytes, or CD4+ and CD8+ cells in equal amounts. UMM showed a variable expression of FasL, ranging from 0 to > 40% of neoplastic cells. Fas was always expressed in TIL, although with a variable extent. A subgroup of UMM showed in TIL a strongly reduced or even absent expression of TCR ζ-chain, involved in activation of T-lymphocytes. This subgroup was characterized by a worse outcome. We hypothesized that an impaired cytotoxic immune response due to the loss of the ζ-chain expression plays a primary role in the biological course of UMM. Our results indicate that the overcoming of the impairment of TCR function may represent a prerequisite for the development of new therapeutic strategies for managing UMM, suggesting that elimination of tumor cells may be possible by activation of cytotoxic cells present within ocular melanomas.

Options for management of intra ocular tumors

The management of intra ocular tumors has undergone a sea change from the era of enucleation or external beam radiation. With the advent of new chemotherapy protocols, globe and vision salvage have become possible in a majority of cases of retinoblastoma. This article is an overview of the various modalities available for the management of intra ocular tumors and their indications. Chemotherapy has been covered elsewhere in this series of articles on ocular oncology. Photocoagulation and cryopexy are easily administered modalities of treatment for small tumors and totally within the ophthalmologist's domain. Slightly larger tumors are treatable with brachytherapy. The susceptibility of the tumors to chemotherapy and radiation decide the choice of treatment and the dosage. Management of intra ocular tumors very often needs a multidisciplinary approach including ophthalmologist, oncologist, radiation physicist, and radiotherapist.

Primary transpupillary thermotherapy for choroidal indeterminate melanocytic lesions

OBJECTIVE

This study aimed to assess the ocular and metastatic outcomes of patients with choroidal indeterminate melanocytic lesions treated by primary transpupillary thermotherapy (TTT).

DESIGN

Retrospective case series.

PARTICIPANTS

Eight patients presenting choroidal indeterminate melanocytic lesions treated by primary TTT.

METHODS

A retrospective chart review was conducted for patients with a newly diagnosed choroidal indeterminate melanocytic lesion treated by at least 3 TTT sessions from 2002 to 2011. Best-corrected visual acuity and lesion dimensions were measured at baseline and during follow-up. Complications were recorded including lesion growth, metastasis, melanoma-related mortality, and treatment-related complications.

RESULTS

Mean initial thickness was 2.0 ± 0.8 mm. Patients had an average of 3.0 ± 0.9 risk factors for lesion growing. Three patients (38%) had lesion growth. Two patients (25%) had severe visual loss (>1.0 logMAR) directly related to TTT treatment. There were no fatalities due to metastasis.

CONCLUSIONS

Despite careful patient selection and systematic treatment with at least 3 TTT sessions, the use of primary TTT to treat patients with choroidal indeterminate melanocytic lesions with ≥ 1 risk factor for lesion growth yielded poor local lesion control and the possibility for severe ocular complications.

Primary transpupillary thermotherapy for choroidal melanoma in 391 cases: importance of risk factors in tumor control

PURPOSE

To report the long-term outcome of primary transpupillary thermotherapy (TTT) for choroidal melanoma.

DESIGN

Retrospective review of medical records.

PARTICIPANTS

We included 391 patients with choroidal melanoma treated between 1995 and 2012 at the Oncology Service, Wills Eye Hospital, Philadelphia.

METHODS

We delivered TTT with an infrared diode laser.

MAIN OUTCOME MEASURES

Local tumor recurrence, Snellen visual acuity after TTT, and distant metastasis.

RESULTS

Of 391 patients, 311 (80%) were treated from 1995 to 2000 and 80 (20%) from 2001 to 2012. Tumors in the 2001 to 2012 group were ultrasonographically thinner (2.2 vs. 2.7 mm), more distant from the optic disc (3.2 vs. 2.5 mm) and foveola (4.0 vs. 2.0 mm), were less often located in the macular area (14% vs. 40%), and had lower rates of acoustic hollowness on B-scan ultrasonography (63% vs. 84%), subretinal fluid (58% vs. 90%), and orange pigment (50% vs. 70%). Kaplan-Meier estimates for tumor recurrence in the 1995 to 2000 group were 29% at 5 years and 42% at 10 years, whereas estimates for tumor recurrence in the 2001-2012 group were 11% at 5 years and 15% at 10 years. Of 108 recurrent tumors 20 were controlled with additional TTT and 62 required plaque radiation (n=60) or proton beam radiation (n=2), with enucleation necessary in 26 patients. Tumor recurrence correlated with the number of high-risk tumor features: 10-year recurrence was 18% in those with 1 or 2 risk factors, 35% in those with 3 to 5 factors, and 55% in those with 6 or 7 factors. On multivariate analysis, features predictive of tumor recurrence were presence of symptoms (P<0.001), shorter distance between the tumor and the optic disc (P=0.026), subretinal fluid (P=0.035), thickness of residual tumor scar (P<0.001), and elevation of residual tumor scar (P<0.001). The only factor predictive of extraocular tumor extension was intraocular tumor recurrence after TTT treated with additional TTT (P=0.007). Presence of orange pigment before TTT (P=0.019), tumor recurrence (P=0.002), and extraocular tumor extension (P=0.017) were predictive of distant metastasis.

CONCLUSION

This study shows a direct correlation between a larger number of high-risk tumor features and higher rates of tumor recurrence after primary TTT of (small) choroidal melanoma. We advise that, when possible, small choroidal melanomas with multiple risk factors be treated with methods other than TTT.

Local treatment failure after globe-conserving therapy for choroidal melanoma

Local treatment failure after globe-conserving therapy for choroidal melanoma is a surgical complication with significant morbidity to the vision and eye. Few reports in the literature have addressed this complication exclusively. A review of the published literature with reference to local treatment failure in the management of choroidal melanoma was performed to make known the potential differences in failure rates between treatment modalities and methods. A search of the literature regarding local treatment failure was performed to identify relevant studies using combinations of the following keywords on PubMed: uveal melanoma, choroidal melanoma, local recurrence, local failure, endoresection, gamma knife, radiotherapy, helium, iodine, proton, palladium, ruthenium, trans-scleral resection, transpupillary thermotherapy. Further studies were found by searching the text and references of previously identified studies for articles reporting local treatment failure rates in choroidal melanoma. Among the 49 studies identified, the local treatment failure rate ranged from 0% to 55.6%, with follow-up ranging from 10 to 150 months. The two most widely used forms of radiation therapy, iodine-125 and ruthenium-106 brachytherapy, were both associated with a local recurrence rate of 9.6%. The weighted-average of treatment failure in all radiation therapies was 6.15% compared with 18.6% in surgical and 20.8% in laser therapies. Rates of local treatment failure for globe-conserving therapy of choroidal melanoma varied widely between modalities and between centres using similar modalities. Radiation therapy overall resulted in lower local treatment failures compared with surgical or transpupillary thermotherapy.

Ocular phototherapy

Phototherapy can be translated to mean 'light or radiant energy-induced treatment.' Lasers have become the exclusive source of light or radiant energy for all applications of phototherapy. Depending on the wavelength, intensity, and duration of exposure, tissues can either absorb the energy (photocoagulation, thermotherapy, and photodynamic therapy (PDT)) or undergo ionization (photodisruption). For phototherapy to be effective, the energy has to be absorbed by tissues or more specifically by naturally occurring pigment (xanthophyll, haemoglobin, and melanin) within them. In tissues or tumours that lack natural pigment, dyes (verteporphin, Visudyne) with narrow absorption spectrum can be injected intravenously that act as focal absorbent of laser energy after they have preferentially localized within the tumour. Ocular phototherapy has broad applications in treatment of ocular tumours. Laser photocoagulation, thermotherapy, and PDT can be delivered with low rates of complications and with ease in the outpatient setting. Review of the current literature suggests excellent results when these treatments are applied for benign tumours, particularly for vascular tumours such as circumscribed choroidal haemangioma. For primary malignant tumours, such as choroidal melanoma, thermotherapy, and PDT do not offer local tumour control rates that are equivalent or higher than those achieved with plaque or proton radiation therapy. However, for secondary malignant tumours (choroidal metastases), thermotherapy and PDT can be applied as a palliative treatment. Greater experience is necessary to fully comprehend risks, comparative benefits, and complication of ocular phototherapy of ocular tumours.

Clinical and histopathologic findings after photodynamic therapy of choroidal melanoma

BACKGROUND

Photodynamic therapy (PDT) has been used occasionally as an alternative treatment for uveal melanomas. The present study describes the clinical and histopathologic features of five choroidal melanomas after PDT.

METHODS

Three patients with pigmented choroidal melanomas were treated with PDT and intravitreal bevacizumab 1 week before undergoing biopsy and brachytherapy to minimize the risks of bleeding during the biopsy. Another two patients received PDT as a primary treatment for peripapillary amelanotic melanomas, one of them also in combination with bevacizumab.

RESULTS

The tumors treated with PDT and bevacizumab showed a marked reduction in tumor vascularity assessed by indocyanine angiography, and the biopsies were conducted without recognizable bleeding, showing viable tumor cells. The tumors receiving PDT as a primary treatment were followed by progressive tumor growth that led to enucleation years after. The histopathology revealed overlying fibrosis with invasion of sclera and optic nerve.

CONCLUSION

Photodynamic therapy and bevacizumab can induce closure of the superficial vasculature of a pigmented choroidal melanoma, but in none of our cases, there was evidence of tumor destruction from this treatment. Preoperative PDT may be useful to reduce the potential of bleeding at the time of tumor biopsy. Our cases do not support the use of a single session of PDT as a primary treatment for pigmented small choroidal melanomas.

Primary transpupillary thermotherapy of choroidal melanocytic lesions

Purpose:

To evaluate the role of primary transpupillary thermotherapy (TTT) in the treatment of choroidal melanocytic lesions.

Materials and Methods:

Retrospective chart review of 24 patients (24 eyes) with choroidal melanocytic lesions, including 20 choroidal melanoma and four choroidal nevus treated with primary TTT. Choroidal nevus cases treated with primary TTT either demonstrated risk factors for growth into an early melanoma or had overlying choroidal neovascularization.

Results:

The mean initial tumor basal diameter was 6.6 (3.0-10.0) mm and the mean initial tumor thickness was 3.0 (1.0-5.0) mm. The mean number of TTT sessions was 2.5 (1-6). The mean decrease in tumor thickness was 1.2 mm (from 3.0 to 1.8 mm) at a mean follow-up of 22.7 (range 3-90) months. On the LogMar scale, visual acuity was stable at 1.0. Complications occurred in 50% of eyes. The most frequent complications were vitreous hemorrhage [5 patients (20.8%)], focal cataract [5 patients (20.8%)], iris atrophy [4 patients (16.6%)] and posterior synechia [4 patients (16.6%)]. There was no significant difference in the complication rate with respect to tumor thickness >3 mm versus tumor thickness ≤3 mm and juxtapapillary versus nonjuxtapapillary location (Fisher’s exact test, P>0.05). Kaplan-Meier curves showed that 9% of eyes develop recurrence by 1 year and 27% develop recurrence by 5 years after primary TTT. Two eyes (8.3%) were enucleated because of neovascular glaucoma and one eye (4.1%) was exenterated because of extraocular tumor recurrence. Globe salvage was achieved in 21 patients (87.5%). One patient (4.1%) with extraocular tumor recurrence developed liver metastasis and expired.

Conclusions:

Although TTT may be useful in the treatment of small choroidal melanocytic lesions, the high complication and recurrence rates warrant close monitoring of patients after primary TTT even when a flat chorioretinal scar has been achieved.

Choroidal melanoma: natural history and management options

BACKGROUND

Choroidal melanoma is the most common primary malignancy of the eye. Enucleation has been the mainstay of treatment, but new and more effective options have recently been proposed as eye- and vision-sparing alternatives.

METHODS

We reviewed the medical literature for trials and case reports involving the evolution, current uses, and limitations of alternatives to enucleation for treating choroidal melanoma.

RESULTS

Options to treat choroidal melanomas depend on the location and size of the tumor and goals of therapy. Local control with plaque radiotherapy has provided overall survival comparable to enucleation. Transscleral resection may leave behind potentially viable melanoma cells following surgery; adjuvant brachytherapy is recommended to irradiate remaining tumor cells. Elevating tissue temperature potentiates the effect of ionizing radiation, thus reducing the dose of radiation needed to treat uveal melanoma. Transpupillary thermotherapy has been effective only in select circumstances, and long-term results have shown poorer local control rates and similar visual outcomes compared with other conservative treatment methods.

CONCLUSIONS

Treatment therapies for choroidal melanoma warrant further study. Currently, enucleation remains as effective as the eye- and vision-sparing approaches.

Primary transpupillary thermotherapy for 18 small posterior pole uveal melanomas

PURPOSE

To evaluate transpupillary thermotherapy (TTT) for the treatment of small uveal melanomas of the posterior pole.

DESIGN

Prospective, nonrandomized interventional case series.

METHODS

Eighteen patients underwent TTT for small uveal melanomas located in the posterior pole of the eyes. Tumors were between 2.5 and 4 mm in thickness. TTT was performed with a diode laser at 810 nm. Patients had between one and three TTT sessions, with an intensity adapted to the coloration of the fundus impact. Biomicroscopic examination, ultrasonographic measurements, and angiography were performed before and two months, four months, and six months after treatment, then regularly during follow-up.

RESULTS

Eight of the 18 tumors regressed and 10 recurred. The one- and two-year metastasis-free survival rates calculated by the Kaplan-Meier method were, respectively, 61.11% to 44.44% (95% confidence interval). Recurrences were managed with enucleation (three patients), proton beam therapy (six), or additional thermotherapy (one). After treatment, visual acuity was maintained or improved for the eight patients with nonrecurrent tumors. Pathologic analysis of the three enucleated eyes revealed scleral invasion.

CONCLUSIONS

Despite encouraging initial short-term results obtained with TTT for the management of small choroidal melanomas, the occurrence of severe complications, especially recurrences and insufficient local tumor control, should raise concern about indications for primary TTT given as isolated treatment for small melanomas of the posterior pole.

TRANSPUPILLARY THERMOTHERAPY

PURPOSE

To correlate changes in primate fundus after transpupillary thermotherapy (TTT) at two wavelengths.

METHODS

Twelve primate eyes were treated with TTT using a wavelength of 635 nm (n=7) or 810 nm (n=5). Laser parameters were as follows: 635 nm (spot size, 1 mm; duration, 30-8 seconds; and fluence [power over time], 20-91.4 J/cm) and 810 nm (spot size, 2 mm; duration, 60 seconds; and fluence, 96-436 J/cm). Fundus photography, fluorescein and indocyanine green angiography, and enucleation were performed at time 0 or 2 weeks after TTT for histologic analysis.

RESULTS

Threshold for fundus lesions (91.4 J/cm at 635 nm and 191 J/cm at 810 nm), acute and chronic retinal damage shown by histologic analysis (79.2 J/cm at 635 nm and 96 J/cm at 810 nm), and choroidal vessel occlusion (50 J/cm at 635 nm and 96 J/cm at 810 nm) were lower at 635 nm. Disorganization of the retina and retinal pigment epithelium was seen for both wavelengths at time 0 and 2 weeks after TTT. Occlusion of the choriocapillaris and choroidal stromal vessels was noted only in specimens obtained 2 weeks after TTT.

CONCLUSIONS

TTT resulted in acute and delayed damage to the neurosensory retina that persisted at 2 weeks. The 635-nm wavelength demonstrated a lower threshold fluence for visible fundus lesions, retinal damage, and choroidal vascular occlusion than the 810-nm laser.

Transscleral thermotherapy with laser-induced and conductive heating in hamster Greene melanoma

The purpose of this study was to investigate the cytotoxic effect of heat as induced by transscleral thermotherapy (TSTT), which may be of interest in the treatment of patients with choroidal melanoma. The aim of TSTT is to heat both the sclera and the tumor up to a cytotoxic temperature of about 60 degrees C. TSTT was performed in hamsters with subcutaneously implanted Greene melanoma covered by a specimen of human donor sclera of thickness 0.5, 0.7 or 0.9 mm. A newly developed applicator, which combines conductive episcleral heating at 60 degrees C with laser-induced heating, was used at laser powers ranging from 500 to 1500 mW delivered by an 810 nm diode laser, beam diameter 3 mm, and exposure time 1 min. Temperatures were measured at the scleral surface and at the sclera-tumor interface. The extent of tumor necrosis was examined by light microscopy and the sclera was examined by polarized light microscopy. Maximal depth of tumor necrosis without scleral damage was 4.4 (SD 1.5) mm. The temperature at the scleral surface after TSTT was 58.8 (SD 2.4) degrees C. The temperature at the sclera-tumor interface ranged from 56.4 (SD 3.7) degrees C at 500 mW to 65.3 (SD 4.4) degrees C at 1250 mW laser power. Structural changes to the scleral collagen started to develop at 1250 mW. TSTT with combined laser-induced and conductive heating caused cytotoxic temperatures in the tumor and the sclera, which were well tolerated by the scleral collagen.

Diagnosis and treatment of orbital invasion in uveal melanoma

The presence of extraocular extension of uveal melanoma is a known prognostic factor that significantly affects patient survival and the risk of orbital recurrence. Interest in this uncommon event in patients with uveal melanoma has been renewed owing to recent reports of extraocular growth after conservative treatment. Ultrasonography and magnetic resonance imaging seem to be the most sensitive imaging techniques to detect even small degrees of extraocular extension. However, some cases are identified at surgery during enucleation or brachytherapy. Although there is a lack of consensus as to the optimal therapeutic management of orbital invasion in uveal melanoma, the current treatment options include isolated resection and modified enucleation or exenteration combined with radiotherapy or other forms of adjuvant therapy.

Recent developments in the management of choroidal melanoma

PURPOSE OF REVIEW

To describe recent advances in the management of choroidal melanoma.

RECENT FINDINGS

During the past 10 years, there has been a trend in the management of choroidal melanoma from enucleation to conservative nonenucleation treatments such as thermotherapy, plaque radiotherapy, charged-particle radiotherapy, and local resection. Recently published information regarding conservative management has revealed that plaque radiotherapy combined with thermotherapy offers 97% tumor control, similar to charged-particle radiotherapy. Additionally, patient survival after treatment of medium-size melanoma is similar when comparing plaque radiotherapy versus enucleation. Risk factors identifying small choroidal melanoma include patient symptoms, tumor thickness more than 2 mm, presence of associated subretinal fluid, presence of orange pigment on the tumor surface, and location of the tumor margin at the optic disc. These factors assist in early detection of choroidal melanoma.

SUMMARY

The management of choroidal melanoma continues to improve with earlier detection of tumors and better treatment methods. Local tumor control is excellent with radiotherapeutic methods. Future studies should investigate control of subclinical metastasis.

Changing concepts in the management of choroidal melanoma

PURPOSE

To review emerging information related to changing concepts in the management of choroidal melanoma.

DESIGN AND METHODS

This perspective reviews and discusses selected studies from the past two decades that have influenced management strategies for large, medium, and small-size choroidal melanomas.

RESULTS

Large choroidal tumors continue to be managed primarily by enucleation. The large tumor trial of the Collaborative Ocular Melanoma Study (COMS) demonstrated neither a positive nor negative effect on 5- and 8-year mortality rates among more than 1000 patients whose eyes containing large choroidal melanomas were randomized to treatment between enucleation alone or enucleation preceded by external radiation. The medium-size tumor trial of the COMS randomized more than 1300 patients between iodine-125 brachytherapy and enucleation. Mortality rates following brachytherapy did not differ from mortality rates following enucleation for up to 12 years after treatment. Iodine-125 has become the most commonly used isotope for brachytherapy in North America. Ten-year follow-up of eyes treated with helium ion and 20 years of experience with proton beam confirm the relative safety and efficacy of these modalities for treatment of choroidal melanoma. Although there is a trend toward earlier treatment of small melanomas, controversy exists regarding the indications for treatment as well as the choice of specific therapy. Recurrences of melanoma after eye-sparing treatment appear to be associated with an increased rate of metastatic disease. Effective adjunctive therapy to prevent or treat melanoma metastasis is lacking.

CONCLUSIONS

Choroidal melanoma is a lethal tumor. Although evidence suggests that patients with untreated choroidal melanomas have a poorer prognosis than patients who receive treatment, our current treatments are unable to prevent tumor-related deaths for many patients. The use of preoperative external radiation as an adjunct to enucleation for large choroidal melanomas is unsupported by data from the COMS trial. The use of radiation with either brachytherapy or charged particles for the management of medium-size choroidal melanomas is well supported on the basis of long-term follow-up studies. There is a trend toward treatment of smaller choroidal melanomas. Treatment of melanomas should be directed toward minimizing the potential for recurrences as recurrent melanomas are associated with an increased rate of metastatic disease. Gains in our ability to manage choroidal melanoma will likely be modest at best until effective systemic therapies can be identified.