Laurence Desjardins

Genomic Profiling and Identification of High-Risk Uveal Melanoma by Array CGH Analysis of Primary Tumors and Liver Metastases

PURPOSE Incurable metastases develop in approximately 50% of patients with uveal melanoma (UM). The purpose of this study was to analyze genomic profiles in a large series of ocular tumors and liver metastases and design a genome-based classifier for metastatic risk assessment. METHODS A series of 86 UM tumors and 66 liver metastases were analyzed by using a BAC CGH (comparative genomic hybridization) microarray. A clustering was performed, and correlation with the metastatic status was sought among a subset of 71 patients with a minimum follow-up of 24 months. The status of chromosome 3 was further examined in the tumors, and metastases with disomy 3 were checked with an SNP microarray. A prognostic classifier was constructed using a log-linear model on minimal regions and leave-one-out cross-validation. RESULTS The clustering divides the groups of tumors with disomy 3 and monosomy 3 into two and three subgroups, respectively. Same subgroups are found in primary tumors and in metastases, but with different frequencies. Isolated monosomy 3 was present in 0% of metastatic ocular tumors and in 3% of metastases. The highest metastatic rate in ocular tumors was observed in a subgroup defined by the gain of 8q with a proximal breakpoint, and losses of 3, 8p, and 16q, also most represented in metastases. A prognostic classifier that included the status of these markers led to an 85.9% classification accuracy. CONCLUSIONS The analysis of the status of these specific chromosome regions by genome profiling on SNP microarrays should be a reliable tool for identifying high-risk patients in future adjuvant therapy protocols.

Relevance of CT and MRI in retinoblastoma for the diagnosis of postlaminar invasion with normal-size optic nerve: a retrospective study of 150 patients with histological comparison

Background Detection of optic nerve invasion is mandatory in children primarily enucleated for retinoblastoma to ensure a free resection margin.Objective To assess the accuracy of CT and MRI for the detection of postlaminar invasion in normal-size nerves.Materials and methods A total of 150 patients enucleated for retinoblastoma were included. Imaging data (119 CT and 46 MRI) were retrospectively reviewed and compared with histological findings. Abnormal contrast enhancement of the optic nerve was used as diagnostic criterion for invasion. The associations between postlaminar invasion and several indirect signs were also assessed. Statistical analysis was performed with the Kruskal-Wallis and Fisher exact tests.Results Postlaminar invasion on histology was observed in 8% (12/150). The sensitivity, specificity, accuracy and negative and positive predictive values were 60%, 95%, 91%, 95% and 60% for MRI, and 0%, 100%, 94% and 94% (PPV not assessable) for CT, respectively. Tumour diameter was the only indirect radiological sign significantly associated with postlaminar optic nerve invasion (P=0.002).Conclusion Our results suggest that MRI is more relevant than CT for preoperative detection of optic nerve invasion in patients with retinoblastoma. Tumour diameter is the only indirect sign significantly associated with postlaminar invasion.

High PTP4A3 Phosphatase Expression Correlates with Metastatic Risk in Uveal Melanoma Patients

A high percentage of uveal melanoma patients develop metastatic tumors predominantly in the liver. We studied the molecular profiles derived from gene expression microarrays and comparative genomic hybridization microarrays, to identify genes associated with metastasis in this aggressive cancer. We compared 28 uveal melanomas from patients who developed liver metastases within three years of enucleation with 35 tumors from patients without metastases or who developed metastases more than 3 years after enucleation. Protein tyrosine phosphatase type IV A member 3 (PTP4A3/PRL3), was identified as a strong predictor of metastasis occurrence. We demonstrated that the differential expression of this gene, which maps to 8q24.3, was not merely a consequence of 8q chromosome overrepresentation. PTP4A3 overexpression in uveal melanoma cell lines significantly increased cell migration and invasiveness in vivo, suggesting a direct role for this protein in metastasis. Our findings suggest that PTP4A3 or its cellular substrates could constitute attractive therapeutic targets to treat metastatic uveal melanomas.

Lacrimal gland malignant mixed tumors (carcinomas arising in benign mixed tumors): A clinico-pathologic study

Six cases of a rare entity, lacrimal gland malignant mixed tumor (MMT), or carcinoma arising in benign mixed tumor (BMT), are presented. Clinically, 2 patients had a long history of orbital protrusion, which recently had progressed more rapidly, In 2 other cases, the carcinomas evolved after recurrences of BMT. Two other patients experienced the recent onset of symptoms, without a known tumor previously having been present. Clinical clues suggesting a malignant neoplasm of a lacrimal gland include 1 recent rapid onset of symptoms (orbital protrusion, eyelid swelling 2 presence of pain; and 3) radiographic studies showing bone destruction. In each of our cases, histologic examination demonstrated a BMT as well as a carcinoma (undifferentiated or poorly differentiated adenocarcinoma; in 1 case, areas of adenoid cystic carcinoma were identified). Problems in histopathologic diagnosis are explored. (BMT, recurrent BMT, in situ carcinoma in BMT and MMT are differentiated.) The management of lacrimal gland tumors is discussed. For a suspected malignant neoplasm, a biopsy through the eye lid to establish the diagnosis is recommended. Radical orbital exenteration should be performed for malignant mixed tumors, which have a poor prognosis.

A deep intronic mutation in the RB1 gene leads to intronic sequence exonisation.

Familial forms of retinoblastoma, an embryonic neoplasm of retinal origin, are caused by constitutional mutations of the RB1 gene. In this paper, we describe a family with retinoblastoma affecting two brothers with no previous family history of cancer. Complete RB1 mutational screening including point mutation and large rearrangement screening failed to demonstrate any mutation. The whole coding sequence was therefore investigated at the cDNA level, demonstrating a 103 bp intronic insertion between exons 23 and 24, leading to subsequent frameshift and premature termination of translation. This intronic exonisation was caused by a deep intronic mutation in intron 23 generating a cryptic 3′ splice site. This is the first report of a deep intronic mutation in RB1 and is a proof of concept that some undetected RB1 mutations should be investigated at the cDNA level, particularly in hereditary forms of retinoblastoma.

Results of a Multicenter Prospective Study on the Postoperative Treatment of Unilateral Retinoblastoma After Primary Enucleation

PURPOSE The objective of this prospective study was to assess overall survival and event-free survival in patients with intraocular unilateral retinoblastoma (Reese-Ellsworth group V) treated by primary enucleation with or without adjuvant therapy depending on histopathologic risk factors. PATIENTS AND METHODS Patients (n = 123) were divided into three groups on the basis of risk factors for extraocular relapse and metastasis assessed on centralized histologic examination of enucleated eyes. Group 1 (n = 70) had minimal or no choroidal involvement and/or prelaminar or no optic nerve involvement and received no adjuvant therapy. Group 2 (n = 52) had massive choroidal involvement and/or intra- or retrolaminar optic nerve involvement and/or anterior segment involvement and received four courses of adjuvant chemotherapy. Group 3 (n = 1) had invasion of the surgical margin of the optic nerve and/or microscopic extrascleral involvement and received six courses of adjuvant chemotherapy with intrathecal thiotepa, consolidation chemotherapy, and autologous stem-cell rescue. Genetic testing was also performed. RESULTS Median follow-up for the 123 patients was 71 months. No disease progression, relapse, or distant metastasis occurred during follow-up. No second malignancies occurred. This requires confirmation with longer follow-up. Secondary bilateralization occurred in two patients with identified RB1 germline mutation. Adjuvant chemotherapy was well tolerated, with limited toxicity. Molecular testing found constitutional RB1 gene mutations in only nine of 100 evaluated patients. CONCLUSION The survival rate of 100% was excellent, including 57% of patients who received no adjuvant therapy, suggesting that chemotherapy could be de-escalated in some patients, especially those with massive choroidal involvement.

Treatment of Uveal Melanoma by Accelerated Proton Beam

Proton beam irradiation of uveal melanoma has great advantages compared to brachytherapy because of the homogenous dose delivered to the tumor and the possibility of sparing normal tissue close to the tumor. We describe the technique of proton beam therapy including the surgical technique of clip positioning, the radiotherapy delivery technique and the dose administered (60 Gy cobalt relative biological effectiveness in 4 fractions). Indications of proton beam are given and the follow-up procedure is described. An inactive residual tumor scar is observed after 2-3 years. Results are given comparing the most recent series of patients treated at the Institut Curie-Orsay proton therapy center with the data published in the literature. The metastasis rate at 10 years varies between 25 and 30%. Local control is excellent. The local recurrence rate at 10 years is usually around 5%. Secondary enucleation is performed in 10-15% of patients either due to complications or local recurrence. Complications such as retinal detachment, maculopathy, papillopathy, cataract, glaucoma, vitreous hemorrhage and dryness are described. The severest complication that usually leads to secondary enucleation is neovascular glaucoma and it is encountered after irradiation of large to extra-large tumors. The toxic tumor syndrome has recently been described. It is hypothesized that the residual tumor scar may produce proinflammatory cytokines and VEGF leading to intraocular inflammation and neovascular glaucoma. Additional treatments after proton beam such as transpupillary thermotherapy, endoresection of the tumor scar or intravitreal injections of anti-VEGF may reduce the rate of these complications.

Long-term results of low-dose proton beam therapy for circumscribed choroidal hemangiomas.

Purpose: To evaluate the long-term efficacy and outcome of low-dose proton beam irradiation in the treatment of symptomatic circumscribed choroidal hemangioma. Patients and Methods: Retrospective review of 71 patients with symptomatic circumscribed choroidal hemangiomas treated by proton beam irradiation between September 1994 and October 2002 using a total dose of 20 Cobalt Gray Equivalent. Results: The median follow-up was 52 months (8–133 months). Retinal reattachment was obtained in all cases. Tumor thickness decreased in all cases and a completely flat scar was obtained in 65 patients (91.5%). Visual acuity was improved by two lines or more in 37 of the 71 patients (52%), and in 30 of the 40 patients (75%) treated within 6 months after onset of the first symptoms. The main radiation complications detected during follow-up were cataract (28%) and radiation-induced maculopathy (8%). None of the 71 patients developed eyelid sequelae or neovascular glaucoma. Conclusion: Proton beam irradiation with a total dose of 20 Cobalt Gray Equivalent appears to be a valid treatment for circumscribed choroidal hemangiomas, inducing definitive retinal reattachment and decreasing tumor thickness. However, delayed radiation-induced maculopathy may occur. A successful functional outcome is dependent on a short interval between onset of the first symptoms and initiation of therapy.

Conjunctival low-grade non-Hodgkin's lymphoma: a large single-center study of initial characteristics, natural history and prognostic factors

To define the initial characteristics and prognostic factors of patients with conjunctival low-grade malignant lymphoma, all patients treated for low-grade lymphoma with initial conjunctival involvement were reviewed. Forty-nine cases were selected, including 45 cases with exclusive ophthalmologic conjunctival involvement. Pathologic review showed 55% of mucosa-associated lymphoid tissue type lymphoma, and 23% of lymphoplasmocytic lymphoma. Initial characteristics were median age of 62 years, nodal involvement in 17% of cases, and stage IV in 22% of patients with 10% of bone marrow involvement. With a median follow-up of 75 months, the 5-year disease-free survival (DFS) and overall survival were 65% and 83%, respectively. On multivariate analysis, nodal involvement was the only factor with a pejorative impact on DFS. Our patient cohort represents one of the largest published series defining the characteristics and prognostic factors of primary conjunctival low-grade malignant lymphoma.

Role of chemotherapy and molecularly targeted agents in the treatment of adenoid cystic carcinoma of the lacrimal gland

Adenoid cystic carcinoma (ACC) is the most common malignant epithelial cancer of the lacrimal gland. Despite a slow rate of growth, ACCs are ultimately associated with poor clinical outcome. Given the rarity of this disease, most recommendations regarding therapy are guided by expert opinion and retrospective data rather than level 1 evidence. Surgery and postoperative radiation therapy are commonly used as initial local treatment. In patients at high risk of recurrence, concomitant platinum-based chemotherapy may be added to postoperative radiotherapy in an attempt to enhance radio-sensitivity. While encouraging responses have been reported with intra-arterial neoadjuvant chemotherapy, this strategy is associated with substantial toxicity and should be considered investigational. For patients with metastatic disease not amenable to surgery or radiotherapy, chemotherapy may have a role based on its modest efficacy in non-lacrimal ACC. Similarly, molecular targeted agents may have a role, although the agents tested to date in non-lacrimal ACC have been disappointing. A better understanding of the biology of ACC will be crucial to the future success of developing targeted agents for this disease.