Langerhans cell histiocytosis: NACHO update on progress, chaos, and opportunity on the path to rational cures.

Langerhans cell histiocytosis (LCH) is a myeloid neoplastic disorder characterized by lesions with CD1a-positive/Langerin (CD207)-positive histiocytes and inflammatory infiltrate that can cause local tissue damage and systemic inflammation. Clinical presentations range from single lesions with minimal impact to life-threatening disseminated disease. Therapy for systemic LCH has been established through serial trials empirically testing different chemotherapy agents and durations of therapy. However, fewer than 50% of patients who have disseminated disease are cured with the current standard-of-care vinblastine/prednisone/(mercaptopurine), and treatment failure is associated with long-term morbidity, including the risk of LCH-associated neurodegeneration. Historically, the nature of LCH-whether a reactive condition versus a neoplastic/malignant condition-was uncertain. Over the past 15 years, seminal discoveries have broadly defined LCH pathogenesis; specifically, activating mitogen-activated protein kinase pathway mutations (most frequently, BRAFV600E) in myeloid precursors drive lesion formation. LCH therefore is a clonal neoplastic disorder, although secondary inflammatory features contribute to the disease. These paradigm-changing insights offer a promise of rational cures for patients based on individual mutations, clonal reservoirs, and extent of disease. However, the pace of clinical trial development behind lags the kinetics of translational discovery. In this review, the authors discuss the current understanding of LCH biology, clinical characteristics, therapeutic strategies, and opportunities to improve outcomes for every patient through coordinated agent prioritization and clinical trial efforts.

A multi-institutional feasibility study of intra-arterial chemotherapy in children with retinoblastoma. A Children's Oncology Group study (COG ARET12P1).

BACKGROUND: Intra-arterial chemotherapy (IA) as a treatment to salvage the eye with advanced retinoblastoma is increasingly utilized based on successes reported by institutions around the world mainly through retrospective studies. OBJECTIVE: To study the feasibility of delivering melphalan directly into the ophthalmic artery in a multi-institutional prospective study in children with newly diagnosed unilateral group D retinoblastoma. METHODS: The Children's Oncology Group (COG) initiated study ARET12P1 in 2014 and was open to nine institutions. Eligible patients older than six months of age were enrolled. The feasibility of delivering three injections of melphalan into the ophthalmic artery every 28 days was assessed. RESULTS: Nine institutions participated in this trial. Fourteen patients were enrolled, two of whom were unevaluable for feasibility. Four patients experienced a feasibility failure. In two patients, the ophthalmic artery could not be accessed for the second IA injection, in one the artery could not be accessed for the first injection, and one patient experienced grade 4 hypotension during the procedure. CONCLUSION: Delivery of prescribed therapy within the context of this study did not meet the feasibility goals of the study with only a 67% feasibility success rate. These results should caution centers that plan to initiate this treatment and suggest investment in training to achieve technical expertise or referral to centers with expertise.

High-risk Pathologic Features Based on Presenting Findings in Advanced Intraocular Retinoblastoma: A Multicenter, International Data-Sharing American Joint Committee on Cancer Study.

PURPOSE: To determine the value of clinical features for advanced intraocular retinoblastoma as defined by the eighth edition of the American Joint Committee on Cancer (AJCC) cT3 category and AJCC Ophthalmic Oncology Task Force (OOTF) Size Groups to predict the high-risk pathologic features. DESIGN: International, multicenter, registry-based retrospective case series. PARTICIPANTS: Eighteen ophthalmic oncology centers from 13 countries over 6 continents shared evaluations of 942 eyes enucleated as primary treatment for AJCC cT3 and, for comparison, cT2 retinoblastoma. METHODS: International, multicenter, registry-based data were pooled from patients enrolled between 2001 and 2013. High-risk pathologic features were defined as AJCC categories pT3 and pT4. In addition, AJCC OOTF Size Groups were defined as follows: (1) less than half, (2) more than half but less than two thirds, (3) more than two thirds of globe volume involved, and (4) diffuse infiltrating retinoblastoma. MAIN OUTCOME MEASURES: Statistical risk of high-risk pathologic features corresponding to AJCC cT3 subcategories and AJCC OOTF Size Groups. RESULTS: Of 942 retinoblastoma eyes treated by primary enucleation, 282 (30%) showed high-risk pathologic features. Both cT subcategories and AJCC OOTF Size Groups (P < 0.001 for both) were associated with high-risk pathologic features. On logistic regression analysis, cT3c (iris neovascularization with glaucoma), cT3d (intraocular hemorrhage), and cT3e (aseptic orbital cellulitis) were predictive factors for high-risk pathologic features when compared with cT2a with an odds ratio of 2.3 (P = 0.002), 2.5 (P = 0.002), and 3.3 (P = 0.019), respectively. Size Group 3 (more than two-thirds globe volume) and 4 (diffuse infiltrative retinoblastoma) were the best predictive factors with an odds ratio of 3.3 and 4.1 (P < 0.001 for both), respectively, for high-risk pathologic features when compared with Size Groups 1 (i.e., < 50% of globe volume). CONCLUSIONS: The AJCC retinoblastoma staging clinical cT3c-e subcategories (glaucoma, intraocular hemorrhage, and aseptic orbital cellulitis, respectively) as well as the AJCC OOTF Size Groups 3 (tumor more than two thirds of globe volume) and 4 (diffuse infiltrative retinoblastoma) both allowed stratification of clinical risk factors that can be used to predict the presence of high-risk pathologic features and thus facilitate treatment decisions.

Metastatic Death Based on Presenting Features and Treatment for Advanced Intraocular Retinoblastoma: A Multicenter Registry-Based Study.

PURPOSE: To evaluate presenting features, tumor size, and treatment methods for risk of metastatic death due to advanced intraocular retinoblastoma (RB). DESIGN: International, multicenter, registry-based retrospective case series. PARTICIPANTS: A total of 1841 patients with advanced RB. METHODS: Advanced RB was defined by 8th edition American Joint Committee on Cancer (AJCC) categories cT2 and cT3 and new AJCC-Ophthalmic Oncology Task Force (OOTF) Size Groups (1: < 50% of globe volume, 2: > 50% but < 2/3, 3: > 2/3, and 4: diffuse infiltrating RB). Treatments were primary enucleation, systemic chemotherapy with secondary enucleation, and systemic chemotherapy with eye salvage. MAIN OUTCOME MEASURES: Metastatic death. RESULTS: The 5-year Kaplan-Meier cumulative survival estimates by patient-level AJCC clinical subcategories were 98% for cT2a, 96% for cT2b, 88% for cT3a, 95% for cT3b, 92% for cT3c, 84% for cT3d, and 75% for cT3e RB. Survival estimates by treatment modality were 96% for primary enucleation, 89% for systemic chemotherapy and secondary enucleation, and 90% for systemic chemotherapy with eye salvage. Risk of metastatic mortality increased with increasing cT subcategory (P < 0.001). Cox proportional hazards regression analysis confirmed a higher risk of metastatic mortality in categories cT3c (glaucoma, hazard ratio [HR], 4.9; P = 0.011), cT3d (intraocular hemorrhage, HR, 14.0; P < 0.001), and cT3e (orbital cellulitis, HR, 19.6; P < 0.001) than in category cT2a and with systemic chemotherapy with secondary enucleation (HR, 3.3; P < 0.001) and eye salvage (HR, 4.9; P < 0.001) than with primary enucleation. The 5-year Kaplan-Meier cumulative survival estimates by AJCC-OOTF Size Groups 1 to 4 were 99%, 96%, 94%, and 83%, respectively. Mortality from metastatic RB increased with increasing Size Group (P < 0.001). Cox proportional hazards regression analysis revealed that patients with Size Group 3 (HR, 10.0; P = 0.002) and 4 (HR, 41.1; P < 0.001) had a greater risk of metastatic mortality than Size Group 1. CONCLUSIONS: The AJCC-RB cT2 and cT3 subcategories and size-based AJCC-OOTF Groups 3 (> 2/3 globe volume) and 4 (diffuse infiltrating RB) provided a robust stratification of clinical risk for metastatic death in advanced intraocular RB. Primary enucleation offered the highest survival rates for patients with advanced intraocular RB.

Response criteria for intraocular retinoblastoma: RB-RECIST.

Standardized guidelines for assessing tumor response to therapy are essential for designing and conducting clinical trials. The Response Evaluation Criteria In Solid Tumors (RECIST) provide radiological standards for assessment of solid tumors. However, no such guidelines exist for the evaluation of intraocular cancer, and ocular oncology clinical trials have largely relied on indirect measures of therapeutic response-such as progression-free survival-to evaluate the efficacy of treatment agents. Herein, we propose specific criteria for evaluating treatment response of retinoblastoma, the most common pediatric intraocular cancer, and emphasize a multimodal imaging approach for comprehensive assessment of retinoblastoma tumors in clinical trials.

Variability in retinoblastoma genome stability is driven by age and not heritability.

Retinoblastoma (RB) is a childhood intraocular cancer initiated by biallelic inactivation of the RB tumor suppressor gene (RB1-/- ). RB can be hereditary (germline RB1 pathogenic allele is present) or non-hereditary. Somatic copy number alterations (SCNAs) contribute to subsequent tumorigenesis. Previous studies of only enucleated RB eyes have reported associations between heritability status and the prevalence of SCNAs. Herein, we use an aqueous humor (AH) liquid biopsy to investigate RB genomic profiles in the context of germline RB1 status, age, and International Intraocular Retinoblastoma Classification (IIRC) clinical grouping for both enucleated and salvaged eyes. Between 2014 and 2019, AH was sampled from a total of 54 eyes of 50 patients. Germline RB1 status was determined from clinical blood testing, and cell-free DNA from AH was analyzed for SCNAs. Of the 50 patients, 23 (46.0%; 27 eyes) had hereditary RB, and 27 (54.0%, 27 eyes) had non-hereditary RB. Median age at diagnosis was comparable between hereditary (13 ± 10 months) and non-hereditary (13 ± 8 months) eyes (P = 0.818). There was no significant difference in the prevalence or number of SCNAs based on (1) hereditary status (P > 0.56) or (2) IIRC grouping (P > 0.47). There was, however, a significant correlation between patient age at diagnosis, and (1) number of total SCNAs (r[52] = 0.672, P < 0.00001) and (2) number of highly-recurrent RB SCNAs (r[52] = 0.616, P < 0.00001). This evidence does not support the theory that specific molecular or genomic subtypes exist between hereditary and non-hereditary RB; rather, the prevalence of genomic alterations in RB eyes is strongly related to patient age at diagnosis.

A single-arm study of systemic and sub-Tenon chemotherapy for Groups C and D intraocular retinoblastoma: A Children's Oncology Group study (ARET 0231).

BACKGROUND: Eyes with Group D intraocular retinoblastoma have low salvage rates. A pilot study showed safety and efficacy of sub-Tenon's fascia carboplatin with systemic chemotherapy supporting further study. METHODS: Children with newly diagnosed bilateral intraocular retinoblastoma with at least one remaining Group C or D eye were treated with six courses of carboplatin/etoposide/vincristine (CEV) with sub-Tenon's fascia carboplatin for Group C/D eyes during courses 2-4. Local ophthalmic therapy started at course 3. The primary study objective was to determine the 1-year failure rate of Group D eyes. RESULTS: The study closed prematurely due to poor accrual and 22 of 30 patients were evaluable for failure rate, contributing 25 Group D and four Group C eyes. Among the 25 Group D eyes, there were 13 failures within the first year of study enrollment including eight needing external beam radiotherapy (EBR) and five needing enucleation, resulting in 1-year failure rate of 52%. The failure rate was significantly lower than the historical rate of 70% (P = .039). The 1-year eye preservation rate for Group D eyes was 80% (20/25). One-year failure rate for Group C eyes was 25% (1/4); 1-year preservation rate was 100% without need for EBR. Systemic toxicity included Grade 3 hearing loss in two subjects, infections, neutropenia, and thrombocytopenia. Ocular toxicities included periorbital fat atrophy (13/29 = 45% eyes), optic nerve atrophy (1/29 = 3% eyes), and restrictive fibrosis (1/29 = 3% eyes). CONCLUSIONS: Sub-Tenon's fascia carboplatin plus CEV was partially effective in Group D intraocular retinoblastoma but had unacceptable ocular toxicities.

Loss of fundus view as an indication for secondary enucleation in retinoblastoma.

In this retrospective study, we evaluated loss of fundus view as an indication for secondary enucleation and associated histopathologic findings. Of 64 secondarily enucleated eyes, 24 were enucleated for loss of fundus view. Average time from loss of fundus view to enucleation was 4.7 months. Of these eyes, 22 had viable tumor cells on histopathology, but none had high-risk features. Loss of fundus view was a common indication for secondary enucleation after chemoreduction. Given the high prevalence of viable histopathologic tumor cells, enucleation for loss of fundus view should not be significantly delayed to decrease risk of high-risk tumor progression.

Not All Seeds Are Created Equal: Seed Classification Is Predictive of Outcomes in Retinoblastoma.

OBJECTIVE: Intravitreal chemotherapy has emerged as an important modality for treating vitreous seeding in retinoblastoma. A classification system has been described as predictive of response to intravitreal melphalan (IVM) in patients treated predominantly with primary intra-arterial chemotherapy. The objective of this study is to evaluate the outcomes of retinoblastoma treated with intravenous chemotherapy and IVM as salvage for vitreous seeding, and further to determine whether vitreous seed classification (dust, spheres, cloud) is predictive of the total number and dose of IVM injections required for treatment in this cohort. DESIGN: A nonrandomized retrospective review. PARTICIPANTS: Retinoblastoma patients treated at a single center with intravenous chemotherapy and IVM. METHODS: Retrospective review of patients with vitreous seeding from retinoblastoma treated with intravenous chemotherapy and IVM from 2012 to 2016. MAIN OUTCOME MEASURES: Primary outcome measure was eradication of seeds and globe salvage. Secondary measures included IVM-associated toxicity and complications. RESULTS: Overall, 28 eyes of 25 patients were included, with a total of 110 IVM injections. By seed classification, eyes with dust (n = 15) required a median of 3 injections, spheres (n = 8) required 4 injections, and clouds (n = 5) required 6 injections. Spherical seeds were only seen in recurrent vitreous seeding. Of the 28 treated eyes, 9 were enucleated, 6 for recurrent retinal disease, resulting in an overall globe salvage rate of 68%. The salvage rate secondary to active retinoblastoma was 79%. Dust classification was the most prevalent seeding type of the 9 enucleated eyes. There was 100% regression of vitreous seeds after intravitreal injection and no eye was treated with radiation or enucleated for seeding. Twelve eyes demonstrated grade 3 or greater IVM-associated retinal or anterior segment toxicity post injection. Mean follow-up was 33 months (range, 9-51 months). CONCLUSIONS: IVM is an effective treatment for vitreous seeding after intravenous chemotherapy for retinoblastoma. As with eyes treated with intra-arterial chemotherapy, seed classification is predictive of the total number and dose of IVM injections in eyes treated with intravenous chemotherapy. Eyes with clouds required significantly more injections than eyes with dust or spheres.

Long-term outcomes of Group D retinoblastoma eyes during the intravitreal melphalan era.

BACKGROUND: To evaluate outcomes of Group D retinoblastoma (Rb) eyes during the intravitreal melphalan era. PROCEDURE: Retrospective chart review of patients diagnosed with Group D Rb from 2011 to 2016 was done. Overall, 76 Group D eyes of 68 patients were included; salvage therapy included systemic chemoreduction with vincristine, etoposide, and carboplatin with local consolidation, followed by intravitreal injection of melphalan for recurrent or persistent seeding. External beam radiation was not used as a treatment modality. Primary outcome measurement was globe salvage. RESULTS: Of 76 Group D eyes, 24 were enucleated primarily and 52 were treated with intent to salvage the globe. Systemic chemoreduction salvaged 25 of 52 eyes (48%). Tumor recurrences were diagnosed in 27 eyes (52%); five with massive retinal recurrences underwent enucleation and 22 were treated with intravitreal melphalan injection. Of the 22 injected eyes, 14 (64%) were salvaged and eight required enucleation primarily for retinal recurrences. Success in eradicating vitreous seeds was 100%. The Kaplan-Meier 3-year survival estimate for treated eyes is 76.5% (95% CI: 61.4-86.3). Median follow-up for the group of 76 Group D eyes was 29.5 months (SD 17.9 months). CONCLUSION: During a 6-year period that included the initiation of intravitreal melphalan at our institution, the salvage rate of treated Group D eyes was 75% (39/52 eyes). Intravitreal melphalan was utilized for ocular salvage in 42% (22/52 eyes). Systemic chemoreduction combined with intravitreal melphalan for seeding demonstrated a high overall salvage rate for Group D eyes in this cohort.

Risk of metastasis and orbital recurrence in advanced retinoblastoma eyes treated with systemic chemoreduction versus primary enucleation.

BACKGROUND: The purpose of this study was to evaluate the risk of metastatic disease and orbital recurrence in advanced retinoblastoma treated with systemic chemoreduction versus primary enucleation. METHODS: A retrospective review of patients with Group D/E retinoblastoma was conducted with data collection from 1995 to 2015. Overall, 345 eyes (294 patients) were included (165 Group D and 180 Group E). Primary outcome measures were orbital recurrence and metastatic disease. RESULTS: Of the 345 eyes, 139 were treated with systemic chemoreduction (102 Group D, 37 Group E) and 206 with primary enucleation (63 Group D, 143 Group E). In the chemoreduction group, one patient developed metastasis (0.7%) and one an orbital recurrence (0.7%). In the primary enucleation group, two patients developed metastases (0.9%) and one an orbital recurrence (0.5%). After systemic chemoreduction, 58 of the 139 eyes (30 Group D, 28 Group E) were secondarily enucleated for treatment failure (41.7%). The median time to secondary enucleation from diagnosis was 8.1 months. None of the eyes in the systemic chemoreduction group had high-risk pathologic features. In the primary enucleation group, 56 eyes had high-risk pathology. CONCLUSION: Over a 20-year period, 345 eyes were treated for advanced retinoblastoma at Children's Hospital Los Angeles. Incidence of orbital recurrence and metastatic disease was <1% and did not vary by treatment modality or group classification. None of the eyes enucleated for treatment failure had high-risk pathology, and none of these patients developed metastatic disease. Globe salvage therapy with systemic chemoreduction and subsequent enucleation for poor response does not increase the risk of metastatic disease or orbital recurrence.

Measuring pediatric hematology-oncology fellows' skills in humanism and professionalism: A novel assessment instrument.

BACKGROUND: Educators in pediatric hematology-oncology lack rigorously developed instruments to assess fellows' skills in humanism and professionalism. PROCEDURE: We developed a novel 15-item self-assessment instrument to address this gap in fellowship training. Fellows (N = 122) were asked to assess their skills in five domains: balancing competing demands of fellowship, caring for the dying patient, confronting depression and burnout, responding to challenging relationships with patients, and practicing humanistic medicine. An expert focus group predefined threshold scores on the instrument that could be used as a cutoff to identify fellows who need support. Reliability and feasibility were assessed and concurrent validity was measured using three established instruments: Maslach Burnout Inventory (MBI), Flourishing Scale (FS), and Jefferson Scale of Physician Empathy (JSPE). RESULTS: For 90 participating fellows (74%), the self-assessment proved feasible to administer and had high internal consistency reliability (Cronbach's α = 0.81). It was moderately correlated with the FS and MBI (Pearson's r = 0.41 and 0.4, respectively) and weakly correlated with the JSPE (Pearson's r = 0.15). Twenty-eight fellows (31%) were identified as needing support. The self-assessment had a sensitivity of 50% (95% confidence interval [CI]: 31-69) and a specificity of 77% (95% CI: 65-87) for identifying fellows who scored poorly on at least one of the three established scales. CONCLUSIONS: We developed a novel assessment instrument for use in pediatric fellowship training. The new scale proved feasible and demonstrated internal consistency reliability. Its moderate correlation with other established instruments shows that the novel assessment instrument provides unique, nonredundant information as compared to existing scales.

Systemic neoadjuvant chemotherapy for Group B intraocular retinoblastoma (ARET0331): A report from the Children's Oncology Group.

PURPOSE: To evaluate a chemoreduction regimen using systemic vincristine and carboplatin (VC) and local ophthalmic therapies to avoid external-beam radiotherapy (EBRT) or enucleation in patients with Group B intraocular retinoblastoma. PATIENTS AND METHODS: Twenty-one patients (25 eyes) were treated with six cycles of VC, accompanied by local ophthalmic therapies after cycle 1. The primary study objective was to determine the 2-year event-free survival (EFS) where an event was defined as the use of systemic chemotherapy in addition to vincristine or carboplatin, EBRT, and/or enucleation. RESULTS: All patients had tumor regression after the first cycle of VC and only two patients had progression during therapy. There were seven treatment failures within 2 years of study enrollment, resulting in 2-year EFS of 65% and early study closure in accordance with the statistical design. The 2-year cumulative incidence of enucleation was 15%; for external beam radiation therapy, it was 10%; and for chemotherapy to control progressive disease, it was 10%. All patients sustaining a treatment failure were salvaged with additional therapy. CONCLUSIONS: For the majority of patients with Group B intraocular retinoblastoma, chemoreduction with VC, without etoposide, in conjunction with local therapy provides excellent opportunity for ocular salvage. Local therapy given with every chemotherapy cycle and incorporation of etoposide may provide improved ocular salvage rates. Central review of group at diagnosis is critical in assigning appropriate therapies.

Management and Outcome of Patients With Langerhans Cell Histiocytosis and Single-Bone CNS-Risk Lesions: A Multi-Institutional Retrospective Study.

BACKGROUND: Children with Langerhans cell histiocytosis (LCH) and single-bone CNS-risk lesions have been reported to be at increased risk of diabetes insipidus (DI), central nervous system neurodegeneration (CNS-ND), and recurrence of disease. However, it is unknown whether the addition of chemotherapy or radiotherapy changes outcomes in these patients. METHODS: Ten pediatric institutions across North America and Europe contributed data of their patients with LCH and single-bone CNS-risk lesions. Clinical information on age, sex, specific craniofacial site involvement, and intracranial extension at diagnosis, therapy, and disease course was collected for all eligible patients. RESULTS: The final analysis included 93 eligible children who were either treated with systemic therapy (chemotherapy, chemo-radiotherapy, or radiotherapy) or local therapy (biopsy, curettage, and/or intralesional steroids). Fifty-nine patients had systemic and 34 had local therapy. The 5-year event-free survival (EFS) and overall survival (OS) were 80 ± 5% and 98 ± 2% in the systemic therapy group versus 85 ± 6% and 95 ± 5% in the local therapy group. There was no statistically significant difference between either group with regard to EFS (P = 0.26) and OS (P = 0.78). On multivariable analysis, there was no significant difference among the two treatment groups after adjusting for site and intracranial soft tissue extension, nor any trend favoring systemic therapy (HR = 2.26, 95% CI = 0.77-6.70; P = 0.14). CONCLUSION: Systemic therapy may not reduce the risk of recurrence or late sequelae in children with LCH and single-bone CNS-risk lesions as compared to local treatment.

Oxaliplatin and Doxorubicin for relapsed or refractory high-risk neuroblastoma.

Patients with relapsed or refractory neuroblastoma have poor long-term survival. New therapeutic regimens are needed. Doxorubicin and cisplatin are commonly used in the treatment of high-risk neuroblastoma. Oxaliplatin, a platinum compound with a 1,2-diaminocyclohexan carrier ligand, is more potent than cisplatin with less nephrotoxicity and ototoxicity. We treated seven relapsed/refractory neuroblastoma patients using oxaliplatin (105-130 mg/m(2)) and doxorubicin (60-75 mg/m(2)) together with dexrazoxane (10 mg/mg of doxorubicin) administered intravenously every three weeks. Prolonged thrombocytopenia causing treatment delay was observed when oxaliplatin was administered at 130 mg/m(2). A reduced dose of oxaliplatin 105 mg/m(2) on day 1 with doxorubicin at 20 mg/m(2)/dose on days 1-3 was well tolerated. Sensory neuropathies were mild and transient. No cardiotoxicity was noted despite all patients having a history of prior anthracycline exposure. Best responses included 1 complete response, 1 partial response, 1 mixed response, 3 stable diseases. In our cohort of heavily pretreated relapsed and refractory neuroblastoma patients, the combination of oxaliplatin and doxorubicin demonstrated anti-tumor activity and merits further investigation.

Outcomes of children younger than 24 months with langerhans cell histiocytosis and bone involvement: a report from a single institution.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare disorder that ranges from single-system to disseminated multisystem disease. Patients younger than 24 months of age more commonly present with risk organ (liver, spleen, hematopoietic system, or lung) involvement at diagnosis and have a poor prognosis. Treatment approaches have changed over the last 25 years. Our goal was to describe the course and outcomes of patients younger than 24 months of age at diagnosis and identify the role of bone involvement in outcomes. METHODS: We conducted a retrospective chart review of patients diagnosed with LCH at Children's Hospital Los Angeles from 1984 to 2010, focusing on 71 patients younger than 24 months of age at diagnosis. RESULTS: Ten patients had single bone lesions at diagnosis and did well irrespective of therapy. The majority of patients (40/71 or 56%) had multiple bone lesions. Of the 37 patients with multisystem disease, 27 children (73%) had risk organ involvement. Fourteen patients with risk organ involvement received ≤ 6 months of initial chemotherapy with prednisone and vinblastine. Six of these patients had reactivation of the disease, and bone was the most frequent site of reactivation. Seven patients with risk organ involvement were treated with at least 12 months of chemotherapy. Only one of these patients had reactivation of the disease, and none died. The majority (7/10) of patients with risk organ involvement who progressed on therapy died despite multiple treatment regimens. CONCLUSIONS: Patients younger than 24 months of age at diagnosis are more likely to have multiple bone lesions than older patients, supporting that a radiographic skeletal survey at the time of LCH diagnosis is important to evaluate the extent of bone involvement. Bones were the most common site for reactivation for all patients. As expected, subjects with risk organ involvement had better outcomes when treated with systemic chemotherapy for at least 1 year. LEVEL OF EVIDENCE: As a retrospective review of all cases at our institution over a 26-year period, this article represents level IV evidence.

Simultaneous colonic adenocarcinoma and medulloblastoma in a 12-year-old with biallelic deletions in PMS2.

We describe a 12-year-old girl, simultaneously presenting with colonic adenocarcinoma and medulloblastoma from bialleic deletions in the mismatch repair gene PMS2. Her distinctive physical and clinical findings are characteristic of constitutional mismatch repair deficiency syndrome. Earlier recognition of such findings may permit better screening and more effective treatment.

Long-term outcomes of Group D eyes in bilateral retinoblastoma patients treated with chemoreduction and low-dose IMRT salvage.

BACKGROUND: To evaluate outcomes of Group D eyes of bilateral retinoblastoma patients treated with primary chemoreduction and external beam radiation as salvage. PROCEDURE: Retrospective chart review of patients diagnosed with bilateral retinoblastoma and designated Group D in at least one eye from January 1, 2000 to December 31, 2009. Overall, 62 Group D eyes of 49 patients were included; 13 had bilateral Group D disease. Primary chemoreduction with vincristine, etoposide, and carboplatin with local consolidation was administered, followed by external beam radiation in the form of intensity-modulated radiation therapy (IMRT) as salvage for recurrent tumor. Primary outcome measure was globe salvage. RESULTS: Of 62 Group D eyes, 7 were enucleated primarily; 55 were treated with systemic chemoreduction, and local therapy. Chemoreduction cured 26 of 55 eyes (47%). Recurrences were found in 29 eyes; 5 underwent enucleation and 24 were treated with IMRT at a dose of 24 Gy (2 eyes) or 36 Gy (22 eyes). Of the 24 irradiated eyes, 19 (79%) were salvaged and 5 required enucleation. Final visual acuity ranged from 20/20 to light perception with 10 eyes having 20/80 or better visual acuity. Average follow-up was 54.2 months. CONCLUSION: Kaplan-Meier estimates of eye survival of Group D eyes in bilateral patients at 12 months is 82% (95% confidence interval [CI] 70.1-89.7%); at 60 months eye survival is estimated to be 68% (95% confidence interval [CI] 55.4-82.8%). Systemic treatment for retinoblastoma demonstrated a high rate of globe preservation with acceptable complications and many eyes retaining functional vision.

Langerhans cell histiocytosis (LCH): guidelines for diagnosis, clinical work-up, and treatment for patients till the age of 18 years.

These guidelines for the management of patients up to 18 years with Langerhans cell histiocytosis (LCH) have been set up by a group of experts involved in the Euro Histio Net project who participated in national or international studies and in peer reviewed publications. Existing guidelines were reviewed and changed where new evidence was available in the literature up to 2012. Data and publications have been ranked according to evidence based medicine and when there was a lack of published data, consensus between experts was sought. Guidelines for diagnosis, initial clinical work-up, and treatment and long-term follow-up of LCH patients are presented.