[Pediatric non-Hodgkin lymphomas]

[An indolent and fluctuating subcutaneous mass of the skull in a 5-year-old patient: Diagnostic approach and difficulties]

A subcutaneous mass of the skull in children can have many different causes (infectious, tumoral, and inflammatory). We report on the case of a 5-year-old patient with a subcutaneous mass of the skull evolving over several months. The first pathological analysis concluded in Kimura disease. The progression and scarcity of this entity in children led to a second pathological analysis that showed lymphoblastic lymphoma B (LLB). This case reminds us that when there are discrepancies between pathological conclusions and clinical progression of a tumoral process, repeated analysis and immunochemistry are necessary.

Disease patterns of pediatric non-Hodgkin lymphoma: A study from a developing area in Egypt

Non-Hodgkin lymphoma (NHL) accounts for 8-10% of all childhood cancers. NHL collectively represents various lymphoid malignancies with diverse clinicopathological and biological characteristics. In this study, we aimed to describe the epidemiological and clinicopathological characteristics and treatment outcomes of pediatric NHL patients treated at the Pediatric Oncology Unit of Zagazig University Hospital and the Benha Specialized Pediatric Hospital. We conducted a cross-sectional retrospective study by reviewing the medical records of 142 patients admitted with a diagnosis of NHL over a period of 8 years (February, 2004 to February, 2012) in these two Oncology Units. The age at presentation ranged between 2 and 15 years, with a mean ± standard deviation (SD) of 6.1±2.8 years and a male:female ratio of 1.7:1. Abdominal involvement was the most common presentation (73.2%). Burkitt's lymphoma (BL) was the most common NHL subtype (69%), followed by lymphoblastic lymphoma, diffuse large B-cell lymphoma and anaplastic large-cell lymphoma, accounting for 18.3, 10.6 and 2.1% of the cases, respectively. The majority of the patients (88.7%) had been diagnosed with advanced disease (Murphy stage III/IV). Complete remission was achieved in 120 cases (84.5%). A total of 16 patients (11.3%) succumbed to the disease during the first few months and 6 patients (4.2%) remained alive following relapse. The mean follow-up duration ± SD was 34.6±25.1 months (range, 3-84 months). The 5-year overall survival (OS) and event-free survival (EFS) rates were 88.7 and 85.1%, respectively. None of the clinical, epidemiological or pathological variables exhibited a statistically significant association with the OS or EFS. In conclusion, NHL occurs at a younger age, with a higher incidence of BL and advanced-stage disease. The outcome of NHL in our two centers was satisfactory, approaching the international rates.

Head and neck presentations of B-NHL and B-AL in children/adolescents: experience of the LMB89 study

PURPOSE

Describe the epidemiology, clinical profiles and outcomes associated with head and neck (H&N) involvement in children/adolescents with B-cell non-Hodgkin lymphoma (B-NHL).

METHODS

Analysis of children/adolescents with H&N B-NHL prospectively enrolled in the SFOP LMB-89 trial (July 1989-June 1996).

RESULTS

One hundred and twelve of 561 patients (20%) had H&N involvement. The mean age of the patients was 8.4 years. Murphy staging differed between the H&N patients and the others (P < 0.0001): 9% versus 5% of the patients presented with stage I disease, 36% versus 11% presented with stage II disease, 12% versus 59% presented with stage III disease, 17% versus 10% with stage IV disease and 27% versus 16% with B-AL. Twenty-nine H&N patients (26%) had CNS involvement at diagnosis versus 8.5% in the group without H&N involvement (P < 0.0001). Patients were treated according to the LMB89 protocol: 3 H&N patients were allocated to group A, 70 to group B and 39 to group C. Ninety-seven percent of H&N patients achieved CR and event-free and overall survival at 4 years was 95.5% (5 deaths in patients with CNS disease). On multivariate analysis, EFS was significantly better in H&N patients than in non-H&N patients (P = 0.021), but not OS (P = 0.11).

CONCLUSION

The H&N site is the second most common location for B-NHL at diagnosis and is more frequently associated with disseminated disease and CNS involvement than other sites. However, outcomes are no worse for these patients than for the rest of the population.

[Pediatric lymphomas diagnosis after needle biopsy in Abidjan: value of cytology versus MYC translocation examination]

OBJECTIVES

In Africa, lymphomas are widely represented by pediatric Burkitt lymphomas. In Abidjan, cytology performed after needle biopsy may be an examination of choice for pediatric lymphomas because of its low cost. We evaluated the value of this cytological examination in comparison with MYC rearrangement assessment.

PATIENTS AND METHODS

A cytological examination was performed after needle biopsy of masses suspected for lymphoma. The reliability of this cytological examination was assessed versus a cytogenetic technique of fluorescence in situ hybridization with a probe targeting locus 8q24 (MYC) which is recurrently rearranged in Burkitt lymphomas.

RESULTS

Thirty-four patients were enrolled in this study. The median age was 8 years old. The main locations of the suspicious masses were maxillofacial and abdominal. Thirty cytological examinations identified cytological aspects of Burkitt lymphoma. Among these cases, the cytogenetic technique identified 24 cytogenetic rearrangements compatible with a translocation involving MYC as described in Burkitt lymphoma. Six cytological examinations identified cytological aspects of Burkitt lymphoma without MYC translocation. Two cytological examinations were not compatible with Burkitt lymphoma and a normal MYC status was observed. Two cytological examinations were technically not contributive.

CONCLUSIONS

The cytological examination showed good performance, notably with excellent sensitivity. The cytological examinations compatible with a Burkitt lymphoma without MYC translocation (6/30=20.0%) could be explained by the absence of translocation involving locus 8q24 (MYC) in some endemic Burkitt lymphomas.

F-18 FDG-PET imaging and correlation with CT in staging and follow-up of pediatric lymphomas

BACKGROUND

We hypothesized that F-18 FDG-PET could be a useful, functional imaging modality for assessing the initial staging, response to therapy and follow-up of children diagnosed with lymphoma.

OBJECTIVE

To assess the role of whole-body F-18 FDG-PET imaging in patients with lymphoma as an initial staging modality and to measure its predictive value for monitoring the response to therapy and disease recurrence compared to CT and clinical follow-up studies.

MATERIALS AND METHODS

As part of their routine clinical care, 24 patients with histologically proven lymphoma (18 Hodgkin disease and 6 non-Hodgkin lymphoma) underwent an F-18 FDG-PET and a CT scan. A total of 28 studies were performed and the entire set of scans retrospectively reviewed. Seven studies were performed for initial staging, 12 for monitoring therapy response and 9 for detecting recurrence. Initial diagnosis was confirmed by histopathology while the gold standard at follow-up was established by clinical follow-up, additional imaging modalities and/or biopsy. F-18 FDG-PET was visually compared to CT on a lesion-by-lesion basis. Fifteen anatomic regions (seven nodal and eight extranodal) were analyzed.

RESULTS

Of the 414 regions analyzed, PET and CT were concordant in 366 (positive in 16 and negative in 350). Discordance was found in 48 regions. Overall sensitivities, specificities, and positive and negative predictive values were 78%, 98%, 94% and 90% for F-18 FDG-PET and 79%, 88%, 90% and 46% for CT, respectively.

CONCLUSION

F-18 FDG-PET imaging is a useful technique for the staging and follow-up of pediatric patients with lymphoma.