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.

Increased risk of systemic relapses associated with bone marrow micrometastasis and circulating tumor cells in localized ewing tumor.

PURPOSE: The presence of metastasis is a major prognostic factor in Ewing tumor (ET). The relapse pattern of patients with localized tumors has long indicated that cases with disseminated ET cells escape detection at diagnosis. ET cells are characterized by specific gene fusions that can be detected with high sensitivity and specificity by reverse transcriptase polymerase chain reaction (RT-PCR). PATIENTS AND METHODS: RT-PCR targeting EWS-FLI-1 or EWS-ERG transcripts was used to search for occult tumor cells in peripheral blood (PB) and bone marrow (BM) at diagnosis in 172 patients with ET, and the prognostic significance of this parameter was assessed. RESULTS: As we suggested previously in a smaller series of patients, RT-PCR positivity of the BM was correlated with a high risk of adverse outcome in the overall study population (P =.007). More interestingly, among patients with otherwise localized tumors, BM micrometastasis also predicted significantly poorer disease-free survival rates (P =.043). The presence of circulating tumor cells (CTC) was more frequently observed in patients with large tumors (P =.006). CTC were associated with a poor outcome among patients with clinically localized disease (P =.045). Patients with clinically localized disease and peripheral occult tumor cells as evidenced by BM and/or PB RT-PCR positivity had axial or proximal tumors and experienced relapses at a systemic rather than at a local level. CONCLUSION: Patients with localized ET and BM micrometastasis or CTC are comparable to patients with metastases in terms of the localization of the primary tumor, outcome, and relapse pattern.

Functional results after treatment of retinoblastoma.

PURPOSE: Because of the long-term complications associated with external beam radiation in retinoblastoma, alternative treatment methods have been investigated. We conducted a retrospective study to evaluate the functional results of new treatment modalities. METHODS: Thirty-seven eyes were treated without external beam irradiation in 31 patients. The median diameter of the largest tumor in each eye was 6 mm. Primary chemotherapy was used in 25 cases, chemothermotherapy was used in 32 cases, cryotherapy was used in 28 cases, iodine 125 Plaques were used in 15 cases, diode laser thermotherapy was used alone in 11 cases, and photocoagulation was performed in 5 cases. The median follow-up after diagnosis of retinoblastoma was 41 months. The visual results were evaluated at a median age of 54 months. RESULTS: The median visual acuity of the treated eyes was 20/33. Twenty-four eyes presented a visual acuity better than 20/40, 4 eyes had a visual acuity between 20/200 and 20/40, and 9 eyes had a visual acuity less than 20/200. Maculopathy was observed in 16 cases, associated with papillopathy in 1 case. A cataract was observed in 1 case and a vitreous hemorrhage was observed in another case. Twenty-one eyes did not develop any complications. No corneal dryness and very few lens changes were observed. CONCLUSION: The functional results after local treatments for retinoblastoma are very good. The most frequent complication is maculopathy, particularly when the tumor involves or is situated close to the macula.