Ans. b. Neuroblastoma (Ref: Schwartz 9/e p1449-1450; Sabiston 19/e p1859-1861; Bailey 25/e p814-815; Harrison 19/e 10 e-2t, 101e-3, 18/e p836; Ghai 7/e p590-591)A 4 years old girl presented with abdominal lump. Bone scan is needed in Neuroblastoma as metastasis is present in 60- 70% of patients at the time of diagnosisQ and MC site of metastasis in older children are bonesQ.Neuroblastoma:MC presentation: Fixed, lobular mass extending from the flank toward the midlineQ of the abdomen.Most (80%) cases present before 4 years and peak incidence is 2 yearsQ of age.Metastasis is present in 60-70% of patients at the time of diagnosisQMC site of metastasis in older children are bonesQ (long bones > facial bones, skull particularly sphenoid), bone marrow and LN. NeuroblastomaArise from neural crestQ and may originate anywhere along the distribution of sympathetic chainMC tumor diagnosed in infants <1 year of ageQMC intra-abdominal malignancy in childrenQSporadic in majority of casesMC site: Adrenal (30%)Q >Paravertebral reteroperitoneumQ (28%) > Posterior mediastinumQ (15%) >PeIvis (5%) >Cervical areaQAssociated with neurofibromatosis, Hirschprung's disease, heterochromia, fetal hydantoin, fetal alcohol syndrome and Freidreich's ataxiaSpontaneous regression is unique behaviour especially in stage 4SQ.Pathology:Classic neuroblastomas: Small, primitive-appearing cells with dark nuclei, scant cytoplasmMitotic activity, nuclear breakdown ('karyorrhexis')Q, and pleomorphism maybe prominent.Homer-Wright pseudo-rosettesQ can be foundImmunochemical detection of neuron-specific enolaseQClinical Features:MC presentation: Fixed, lobular mass extending from the flank toward the midlineQ of the abdomen.Most (80%) cases present before 4 years and peak incidence is 2 yearsQ of age.Metastasis is present in 60-70% of patients at the time of diagnosisQMC site of metastasis in older children are bonesQ (long bones >facial bones, skull particularly sphenoid), bone marrow and LN.In infants metastasis is confined to liver or subcutaneous tissueQ.Lung metastasis are rareQ in neuroblastomaOrbital metastasis commonly present with peri-orbital ecchymoses and proptosis called as Raccoon eyesQ.Infants with stage 4S may display cutaneous metastasis called as blueberry muffin lesionsQ.Chronic watery diarrheaQ (due to secretion of VIP) and opsoclonus-myoclonusQ (Dancing eyes, dancing feetQ) are unusual paraneoplstic manifestations.Diagnosis:Anemia, thrombocytopenia or thrombocytosis (more common)Increased LDH, ferritin, urinary catecholamines and neuron specific enolaseX-ray or CT: Stippled calcificationQ (MC abdominal tumor to demonstrate calcification prior to chemotherapy)Drooping Lily sign: Neuroblastoma displaces kidney inferolaterallyQMRIQ is superior to CT in assessing vessel encasement, vessel patency, spinal cord compression and bone marrow involvement.MIBG scan or SRS are used in the diagnosis of primary, residual and metastatic neuroblastoma.MIBG is one of the single best studies to document the presence of metastaticQ disease.Appearance of neuroblastoma in bone marrow may simulate the appearance of ALLQ, differentiation can be done by monoclonal antibody phenotypeQ.Treatment:Localized neuroblastoma: ExcisionQUnresectable tumor: Biopsy, initially treated by chemotherapy and radiotherapy followed by surgical resection of residual tumorQDisseminated disease: ChemotherapyQ (Cyclophosphamide, vincristine, dacarbazine, doxorubicin, Cisplatin)Prognosis:Shimada classificationQ describes prognosis based on the degree of differentiation, mitosis-karyorrhexis index, presence or absence of schwannian stromaQ.Prognostic Factors in NeuroblastomasVariableFavorableUnfavorableStageStage 1, 2A, 2B, 4SQStage 3, 4QAge<18Q months>18 monthsEvidence of schwannian stroma and gangliocytic differentiationPresentQAbsentMitosis-karyorrhexis index<200/5000 cells>200/5000 cellsDNA ploidyHyperdiploid or near-triploidQNear-diploidN-MYCNot amplifiedAmplifiedQChromosome 17q gainAbsentPresentQChromosome 1p lossAbsentPresentQChromosome 11q lossAbsentPresentQTRKA expressionPresentQAbsentTRKB expressionAbsentPresentQTelomerase expressionLow or absentHighly expressedQDevita 9/e p1766-1769; Nelson 18/e p2140; Smith 17/e p339-343; Campbell 10/e p3714-3722; Bailey 25/e p1308Wilm's TumorWilm's tumor: MC primary renal tumor of childhood (2-5 years)Q.Wilm's tumor: 2nd MC malignant abdominal tumor in children (MC is neuroblastoma).Arise from kidney, composed of three elements- blastema, epithelium and stromaQ.MC presenting feature is asymptomatic abdominal mass or swellingQ.Mostly unilateral.Characterized by triad of abdominal mass, fever and microscopic hematuriaQ.Fever typically resolve after tumor resectionMC site of metastasis: LungsAssociated malformationsWAGR SyndromeQ: It consists of aniridia, genital anomalies and mental retardation. The risk of Wilm's tumor is increased by 33% in this syndromeQ.Denys-Drash SyndromeQ: It consists of gonadal dysgenesis (Male pseudohermaphroditism), nephropathy leading to renal failure. Majority of patients with this syndrome have renal failure.Beckwith-Wiedmann SyndromeQ: It consists of enlargement of body organs, hemi-hypertrophy, renal medullary cysts and abnormal large cells in adrenal cortex, macroglossia, omphalocele.Diagnosis:USG (most important investigation)Q or CT abdomen for staging.MRI is superior to other imaging modalities in delineating nephroblastomatosis elements.Calcification tends to be more crescent shaped, discrete and peripheralQ in comparison of finely stippled calcification of neuroblastoma.Treatment:Surgical excision is treatment of choice.Routine exploration of contralateral kidney is not necessary if imaging is satisfactory and does not suggest bilateral process.In unfavorable histology, Radiation therapy should be started within 10 daysQ after nephrectomy, chemotherapy should be started 5 days after surgeryQ.Chemotherapy: VCD (Vincristine + Cyclophosphamide + Doxorubicin or dactinomycin)Whole lung irradiation is recommended for pulmonary metastasis.Preoperative treatment should be consideredSolitary kidneyQBilateralQ renal tumorsTumor in horse shoe kidneyQTumor thrombus in IVC above the level of hepatic veinsQRespiratory distress due to metastaticQ diseasePrognosis:The histologyQ of Wilm's tumor and tumor stage is identified as most important determinant of prognosisQ (Histology >Stage).Pediatric Tumors* MC malignant tumor of infancy* MC extracranial solid tumor in children* MC abdominal malignancy in childrenNeuroblastoma* MC primary malignant renal tumor of childhoodWilm's tumor* MC renal tumor of infancyCongenital mesoblastic nephroma* MC soft tissue tumor in infants and childrenRhabdomyosarcoma* MC solid tumor of childhoodBrain tumor* MC cancer of childhoodLeukemia (30%) >Brain tumors (22%)