Case report: Delayed retinoblastoma relapse in a lymph node after 9 years of complete remission

Retinoblastoma (RB) is the most common primary intraocular malignancy of childhood. Recurrence of RB often occurs within 6 months to 1 year after the end of treatment. Orbital tissue is the most common site of recurrence in children who have undergone enucleation; other sites include the central nervous system, bone, bone marrow, lymph nodes, and other organs. Here, we describe an adolescent girl who presented with RB recurrence and metastasis in a distant lymph node after 9 years of complete remission. The tumor was an incidental finding during a routine examination and was misdiagnosed as lymphadenitis. After histopathologic examination of an aspiration biopsy sample, the correct diagnosis of recurrent metastatic RB was made. Systemic chemotherapy and surgical excision were provided; the patient remained tumor-free during the 6-month follow-up period. RB often relapses within 1 year after treatment; orbital tissue is the most common site of recurrence. However, our patient's case was unique in terms of delayed relapse and the presence of a single metastatic site; these findings may provide new insights into the behavior of RB. Furthermore, this case report indicates the need for lifelong follow-up of children with RB. Oncologists should be vigilant when treating patients with a history of RB, because complete remission does not mean complete safety; long-term recurrence and metastasis may occur. Lifelong follow-up is necessary for children with RB. Complete remission might be achieved after active and standardized treatment.

Transformation of Grade II to Grade III Rhabdoid-Papillary Meningioma: Is Stereotactic Radiosurgery the Culprit? A Case Report and Literature Review

BACKGROUND

In the management of meningiomas, single-fraction stereotactic radiosurgery (SRS) is an established alternative treatment to surgical resection. However, its effects on tumorigenesis and malignant transformation are still uncertain.

CASE DESCRIPTION

We have described a grade II parafalcine meningioma that was initially surgically resected (Simpson 2 clearance) and then managed with a single dose of SRS on recurrence. The tumor recurred again 7 years later, with histological features of a grade III rhabdoid-papillary lesion, with local brain invasion.

CONCLUSION

To the best of our knowledge, this is the first report to describe malignant transformation of a grade II to grade III meningioma after SRS to date.

Radiation-Induced Meningiomas: An Exhaustive Review of the Literature

OBJECTIVE

Radiation-induced meningioma (RIM) is an uncommon late risk of cranial irradiation. We conducted an exhaustive review of individual patient data to characterize RIM.

METHODS

Using a systematic search of the PubMed database, we performed a comprehensive literature review to characterize and investigate RIM. Student t tests were used to evaluate differences between variables. A Kaplan-Meier analysis was used to assess survival. Statistical significance was assessed using a log-rank test.

RESULTS

Our analysis included 251 cases of RIM. The average age at onset for the primary lesion was 13.0 ± 13.5 years, and the average radiation dose delivered to this lesion was 38.8 ± 16.8 Gy. Secondary meningiomas could be divided into grades I (140), II (55), and III (10) tumors. Thirty patients (11.9%) had multiple lesions, and 46 (18.3%) had recurrent meningiomas. The latency period between radiotherapy for primary lesions and the onset of meningiomas was 22.9 ± 11.4 years. The latency period was shorter for patients with grade III meningioma and for those in the high-dose and intermediate-dose radiation groups who received systemic chemotherapy. Aggressive meningiomas and multiple meningiomas were more common in the high-dose and intermediate-dose groups than in the low-dose group. The 5-year and 10-year survival rates for all patients with meningioma were 77.7% and 66.1%, respectively.

CONCLUSIONS

For patients treated with cranial radiotherapy, the risk of secondary meningioma warrants a longer follow-up period beyond the standard time frame typically designated for determining the risk of primary tumor relapse.

Secondary malignancy following radiotherapy for thyroid eye disease

AIM

To describe the first case of a secondary meningioma in a patient after radiation treatment for thyroid eye disease (TED). Secondarily to identify any additional cases of secondary malignancy resulting from radiotherapy for thyroid eye disease from our institutional experience.

BACKGROUND

Thyroid eye disease (TED) is a self-limiting auto-immune disorder causing expansion of orbital soft tissue from deposition of glycosaminoglycans and collagen, leading to significant cosmetic and functional morbidity. Established management options for TED include: glucocorticosteroids, orbital radiotherapy, and surgical orbital decompression. Two large series on radiotherapy for TED have been reported without any cases of secondary malignancy.

MATERIALS AND METHODS

The case of a patient with visual failure, found to have a sphenoid wing meningioma after previous TED radiotherapy is described. We then reviewed 575 patients with at least 3-year follow-up receiving radiotherapy for TED at British Columbia Cancer Agency to identify other possible secondary malignancies.

RESULTS

The patient had postoperative improvement in her vision without any identified complications. Three additional cases of hematologic malignancy were identified. The calculated risk in our population of developing a radiation-induced meningioma after TED with at least 3 years of follow-up of is 0.17% (1/575); with hematopoetic malignancies the risk for secondary malignancy is 0.7% (4/575).

CONCLUSIONS

Our calculated risk for secondary malignancy (0.17%, 0.7%) is similar to the reported theoretical risk published in the literature (0.3-1.2%). There is real risk for the development of a secondary malignancy after radiotherapy treatment of TED and treatment options should include consideration for this potential.