The rare translocation t(14;21)(q11;q22) detected in a Moroccan patient with T-cell acute lymphoblastic leukemia

Cytogenetic studies of acute lymphoblastic leukemia have been at the forefront of research in the pathogenesis of cancer. The presence of recurring chromosomal abnormalities (either numeral or structural rearrangements) provides immediate clues to the genetic events leading to leukemia and many abnormalities have important prognostic significance. The rare translocation t(14,21)(q11.2;q22) has been described in pediatric T lineage ALL in only one case so far in 2000. The present study is a case report of an ALL case in which we found a t(14,21)(q11.2;q22) as a non random chromosomal abnormality among 70 analyzed pediatric ALL cases referred exclusively to BIOLAB Laboratory from the children hospital of Morocco.

[Thymic hyperplasia following treatment for nephroblastoma]

Thymic hyperplasia in response to stress is a well known phenomenon. Thymic hyperplasia has also been described after chemotherapeutic treatment for malignancies in children.

CASE REPORT

A three-year-old girl was followed up from the age of 18 months for a left kidney nephroblastoma treated by combination of chemotherapy (vincristin, actinomycin and adriamycin) and surgery. Assessment at the end of treatment was normal. Four months after the end of treatment, pulmonary radiography showed mediastinal enlargement, which was shown to originate in the thymus at thoracic CT scan. A recurrence of the disease was suspected. Biopsy showed thymic hyperplasia without evidence of tumor cells. Mediastinal enlargement then disappeared spontaneously 2 months later.

CONCLUSION

Thymic hyperplasia occurring during remission of a cancer treated by chemotherapy is a diagnostic dilemma as it suggests mediastinal reccurence of the disease. Needle aspiration cytology is an appropriate investigation in thymic hyperplasia. No steroid therapy should be used before histologic diagnosis of thymic hyperplasia.

Histiocytose langerhansienne à localisation orbitaire

PURPOSE

Langerhans' cell histiocytosis is a rare disease representing less than 1% of orbital tumors.

METHODS

We report a case of Langerhans cell histiocytosis with orbital involvement in a 9-year-old boy. He presented with an inflammatory swelling if the left lateral orbital wall. The computed tomographic scan revealed an orbital cellular mass with lytic bone lesion within the orbital roof and intracranial enlargement.

RESULTS

The cytological study after a biopsy showed infiltrates of histiocytes derived from Langerhans cells. Diagnosis was confirmed by immunohistochemistry, which identified positive staining with anti-S100 and anti-CD1a antibodies. The rapidly expanding orbital tumor, posing a threat of ocular compression as well as intracranial spreading, was treated by chemotherapy (Vinblastine) combined with a steroid.

CONCLUSION

A 2-year follow-up showed no evidence of recurrence or systemic involvement. According to this observation, the authors describe the clinicopathological and histological features of orbital involvement in Langerhans cell histiocytosis.

Sarcome rénal à cellules claires. À propos d'une série de 13 cas

Clear cell sarcoma of the kidney (CCSK) also called a "bone-metastasizing renal tumor of childhood" is the second common pediatric renal neoplasm. This tumor is associated with a higher rate of relapse and a wider distribution of metastases than Wilms' tumor.

PATIENTS AND METHODS

We have reviewed records of 13 cases of CCSK among 277 renal tumors (5%) diagnosed at the children's hospital of Rabat between 1990 and 2002.

RESULTS

The median age at diagnosis was 14 months (5 months-9 years). The male to female ratio was 5.5:1.00. Abdominal mass, usually the first physical finding, was associated with hematuria in four cases. No congenital malformation syndrome or familial Wilms' tumor were observed. Imaging studies found out seven right and six left intrarenal processes. Preoperative chemotherapy was given according to the SIOP9, SIOP93-01 and GFAOP 98 protocols. Twelve of 13 children underwent nephrectomy. Tumor measurements varied through 450-3450 g and 7-26 cm. The classic morphologic pattern was seen in nine cases (69%). The distribution local stage was I: three cases; II: three cases; III: six cases; IV: one case. Postoperative chemotherapy and radiotherapy (21 600-30 600 cGy) was done in 10 cases. With a median follow up of 44 months, four patients showed bone metastases (31%), four are alive in CR, four are lost for follow up and five died.

CONCLUSION

CCSK remains the pediatric renal tumor most frequently misdiagnosed. Its aggressiveness and its ability to give bone metastases need to recognize early this diagnosis for an adapted treatment.

[Non-Hodgkin's lymphoma with protein S deficiency]

Venous thrombosis is rare in children. It can be either acquired or of constitutional origin. Thrombosis during non-Hodgkin lymphoma remains exceptional and is usually locally associated to the tumoral process, raising the issue of its tumoral or cruoric nature. The treatment is based on anticoagulation concomitantly to chemotherapy. We report on a 4-year-old boy admitted for mediastinal non-Hodgkin lymphoma, who developed a thrombosis of the superior vena cava associated to protein S-deficiency. The mechanism of thrombosis may have been multifactorial: associated protein S-deficiency, vascular compression, tumoral process and chemotherapy.

[Intracerebral granulocytic sarcoma. A case report]

Granulocytic sarcoma is a tumor composed of proliferating myeloblastic cells, generally found in the orbit. A brain localization is rare. We report the case of a 11-year-old boy treated in our unit for acute myeloblastic leukemia (AML 4 Eo. FAB). After 21 months of complete remission, he developed headache and facial palsy. The CT scan visualized the presence of two frontal and occipital masses. The spinal tap revealed blastic cells in the CSF. The study of the bone morrow showed medullar relapse. A new medullar and cerebro-meningeal remission was obtained with chemotherapy and radiotherapy. CSF and the bone marrow studies can help avoid stereotaxic biopsy can be avoided in this type of tumor