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TUMORS

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TUMORS

A. Wilms Tumor




This is the most common solid intra-abdominal tumor (malignant) in children. It affects 450-500 children annually in the USA. Neuroblastoma is most common, but they are not all confined to the abdomen. It has a peak incidence at 3-5 years of age. Present as abdominal or flank mass with abdominal pain, asymptomatic hematuria, and occasionally fever. Other presentations: malaise, weight loss, anemia, left varicocele (obstructed left renal vein), hypertension. Abnormalities associated with Wilms tumor include hemihypertrophy, pseudohermaphroditism, aniridia, Beckwith-Wiedemann syndrome, trisomy 18 and other genitourinary anomalies.

The initial evaluation consists of: abdominal films, ultrasound, IVP, urinalysis, and chest-X-rays and tomography. The presence of a solid, intrarenal mass causing intrinsic distortion of the calyceal collecting system is virtually diagnostic of Wilms tumor. Sonography can be of help to evaluate the IVC and renal veins (venous extension of the tumor). Metastasis most common in the lung and occasionally the liver.

Operation is for both treatment and staging to determine further therapy. The abdomen is explored by a large transverse incision and both kidneys are visualized. Nodes are biopsied to determine extent of disease.

Staging by National Wilms Tumor Study Group:

Group I- tumor limited to kidney and completely resected.

Group II- tumor extends beyond the kidney but is completely excised.

Group III- residual non-hematogenous tumor confined to the abdomen.

Group IV- hematogenous metastasis.

Group V- bilateral tumors.

Further treatment with chemotherapy or radiotherapy depends on staging and histology (favorable vs non-favorable) of tumor. Non-favorable histologic characteristics are: anaplasia (enlarged nucleus 3X, hyperchromatism, mitosis), sarcomatous or rhabdoid degeneration.

Disease-free survival is 95% for Stage I and approximately 77% for all patients. Poor prognosis for those with lymph nodes, lung and liver metastasis.

Congenial Mesoblastic Nephroma presents in infants under 30 days of age (< 6 months), is commonly benign and invasive locally. Operative removal is curative, ruptured of tumor increases recurrences. Chemo, radiotx not indicated. 

B. Neuroblastoma

Neuroblastoma is the most common solid tumor of infancy and childhood. Most appear during the first five years of life; over half occur in children under 2 years of age. Two-thirds of children over 2 years of age have disseminated disease at presentation.

Neuroblastomas can occur at any site where neural crest tissue is found in the embryo and are derived from primordial neural crest cells and neuroblasts migrating from the mantle layer of the developing spinal cord into the sympathetic ganglion chain and the adrenal medulla. The etiology is unknown. About three-fourths of neuroblastomas arise in the abdomen; half of these originate in the adrenal gland. About 20% occur in the posterior mediastinum. Other uncommon sites include the pelvis (4%), and the neck (4%). It's a solid, highly vascular tumor with a friable pseudocapsule.

Staging:

Stage I- tumor limited to organ of origin.

Stage II- regional spread that does not cross the midline.

Stage III- tumor extending across the midline.

Stage IV- distant metastasis.

Stage IV-S patients with a small primary and metastases limited to liver, skin, or bone marrow without radiographic evidence of bone metastases.

The clinical presentation is an abdominal mass (50-75%), hypertension (25%), weight loss, diarrhea, fever, bone pain. Rare: 'opso-myoclonus' (dancing eye syndrome), Horner's syndrome, Panda's eyes, VIP syndromes.

Diagnostic work-up includes: IVP, ultrasound, chest films, KUB (fine stipple calcifications 50%), skull x-rays, urinalysis, CBC, Urine VMA, HVA, and bone marrow aspirate. Other markers: cystathione, homoserine, neuron-specific enolase and ferritin.

The surgical goal is complete removal of the tumor when possible. Unfortunately, metastases are present in 60-90% of patients at diagnosis. Even in these patients attempts to reduce the bulk of tumor is important. Further treatment with radiation and chemotherapy depends on stage and extent of metastases.

There is a 100% survival for stage I, although this stage is extremely rare. Survival for stage II is 75%, stage III is 35%, stage IV 10-20%, and stage IV-S is about 80%. Age is an important prognostic factor, with 75% survival in children less than one year; 50% in children 1-2 years of age; 25% in children 2-3 years of age, and 15% in children over 3 years. Other prognostic factors are related to stage, nutritional status, site of primary, maturity state of tumor, VIP tumor (+), positive lymph nodes (-), high ferritin, NSE, and Diploid DNA levels(-).

Routine use of prenatal sonography will increase the incidental diagnosis of fetal neuroblastoma. Most are detected during the third trimester of pregnancy as cystic/solid suprarenal mass. The tumor does not cross the placenta but can metastasize in utero to the fetal liver or placenta. After birth 50% of babies have elevated HMA/VMA levels. Most enjoy improved survival due to: lower stage of disease, cystic variety (in‑situ), and higher stage IV-S (which has been associated with spontaneous immuno-regression. Adverse biologic features are: diploid tumor karyotype (cytometry) and amplify N-myc oncogene. They can be very difficult to differentiate from neonatal adrenal hemorrhage; T2 of MRI can be of help. Are they neuroblastoma in-situ, and will they regress spontaneously without treatments are question waiting answer in the near future.

Opsoclonus-myoclonus-ataxia (OMA) syndrome is a rare paraneoplastic or paraviral neurologic syndrome commonly associated with neuroblastoma. Less than 3% of children with neuroblastoma develop OMA syndrome. Clinically the child with OMA syndrome develops an acute onset of rapid chaotic eye movements, myoclonic jerking of the limbs and extremity and ataxia. OMA is believed to be an immune-mediated disorder due to the detection of antineural, antineurofilament and anti-Hu antibodies. The child with OMA syndrome caused by neuroblastoma has a favorable staged disease due to rapid work-up and findings that the patient’s immune response to the tumor limits the metastatic and growth potential of the tumor. Rarely do these tumors shows n-MYC gene amplification, a poor prognostic finding. Children with neuroblastoma and OMA have an excellent survival. There is no correlation with duration of symptoms and late neurologic outcome. Most children respond to treatment of acute symptoms with steroids or ACTH. Late neurologic sequelae (delay in motor function, speech and cognition) of OMA children can be drastic and affect quality of life. Children with advanced stage disease require more intensive chemotherapy and have better outcomes with regard to late neurological sequelae.  The higher the immune response limits the spread of disease but increases the neurologic sequelae.



C. Rhabdomyosarcoma

Most common soft tissue sarcoma in infants and children and represents about 5-15% of all solid malignant lesions. It has a peak incidence at age 2-5 years. Second surge between 10-15 years of age. Tumors of the pelvic organs and head and neck are more prevalent in infancy and early childhood, while the paratesticular rhabdomyosarcomas are largely a disease of adolescents and young adults.

Although classically described as occurring in striated muscle, rhabdomyosarcomas arise from a primitive cell type and occur in mesenchymal tissue at almost any body site (possibly excluding the brain), including many organs that normally do not have striated muscle. The predominant histologic type in infants and small children is embryonal. The botryoid rhabdomyosarcoma is a subtype of the embryonal variety, which ordinarily extends into body cavities such as the bladder, nasopharynx, vagina, or bile duct. The alveolar cell type, named for a superficial resemblance to the pulmonary alveoli, is the most common form found on the muscle masses of the trunk and extremities, and is seen more frequently as age advances.

The clinical findings, diagnostic evaluation and therapy employed are dependent upon the location of the primary tumor and is beyond the scope of this review. In brief, head and neck tumors are most common and occur in the orbit, nasopharynx, cheek, neck, middle ear, larynx and paranasal sinuses. Most are treated by simple biopsy followed by combined therapy or preoperative chemotherapy and radiation followed by conservative resection. Operations for extremity lesions include wide local excision to remove as much of the gross tumor as possible. Rhabdomyosarcomas can arise from the bladder, prostate, uterus, or vagina. The trend in treatment is more chemotherapy and conservative surgical management.

D. Liver Tumors

Hepatoblastoma and hepatocellular carcinoma are the most common malignant tumor of liver. These represent about 2% of all malignancies in childhood and 15% of malignant abdominal masses.

Hepatoblastoma (HB) is the most common primary malignant neoplasm of the liver in children mostly seen in males less than four year of age. Diagnostic work-up (US, Scintigraphy, CT-Scan) objective is predicting resectability and tumor extension. Diagnostic laparotomy will decide resectability. Markers associated to this tumor are: alpha-fetoprotein and gamma-glutamyltransferase II. Only reliable chances of cure is surgical excision although half are unresectable at dx. Unresectable tumors can be managed with preop chemotx. Disadvantages of preop chemotx are: progressive disease, increase morbidity, post-op complications, and toxicity. Advantages are: decrease in tumor size, covert three-fourth cases into resectable, although extent of surgery is not decreased. Tumor necrosis is more extensive in pt. receiving preop chemotx. Osteoid present in tumors after chemotx may represent an inherent ability of the tumor to maturate and differentiate. Diploid tumors on DNA flow cytometry show a better prognosis.

Hepatocellular carcinoma in childhood is histologically identical to hepatoma seen in the adult and is associated 50% of the time to a prior liver disorder (i.e. tyrosinemia, hepatitis type B, etc.).

Associated anomalies and conditions are: hemihypertrophy, osteoporosis, lipid storage disease, glycogen storage disease, virilization in males. Clinical presentation is asymptomatic abdominal mass, with abdominal pain and weight loss in 25% of patients.

Diagnostic work-up includes: alpha-fetoprotein, chest x-ray, abdominal films, IVP, ultrasound, liver-spleen scan, CAT scan, and occasionally arteriogram.

Hepatic resection has provided the only cures. In patients with initially unresectable tumor or in post-resection patients, chemotherapy is employed. Among those patients in whom the entire tumor can be resected, survival is 80% at two years. Unresectable tumors have a dismal prognosis. ADR (Adriamycin) is the principal chemotherapeutic agent.

E. Teratomas

Teratomas contains tissues derived from the three embryonic layers (endoderm, mesoderm, and ectoderm), found in a locus that does not normally harbor such tissues. It is not always possible to find tissue in each teratoma that is derived from all three embryonic layers.

Sacrococcygeal teratoma (SCT) is the most common extragonadal germ cell tumor in neonates with an incidence of one in 30-40,000 live births. Three-fourth are females. SCT present as a large, firm or more commonly cystic masses that arise from the anterior surface of the sacrum or coccyx, protruding and forming a large external mass. Histology consists of tissue from the three germ cell layers. SCT is classified as: mature, immature, or malignant (endodermal sinus) and produces alpha-feto protein (AFP). Prenatal sonographic diagnostic severity criteria are: tumor size greater than the biparietal diameter of the fetus, rapid tumor growth, development of placentomegaly, polyhydramnios and hydrops. Large tumors should benefit from cesarean section to avoid dystocia or tumor rupture. Management consist of total tumor resection with coccyx (recurrence is associated with leaving coccyx in place). Every recurrence of SCT should be regarded as potentially malignant. Malignant or immature SCT with elevated AFP after surgical resection will benefit from adjuvant chemotherapy. Survival is 95% for mature/immature tumors, but less than 80% for malignant cases. Follow-up should consist of (1) meticulous physical exam every 3-6 months for first three years, (2) serial AFP determination, (3) fecal/urodynamic functional studies. Long term F/U has found a 40% incidence of fecal and urinary impairment associated to either tumor compression of pelvic structures or surgical trauma.

Mediastinal teratomas are rare tumors that originate in the anterior mediastinum and comprise almost one-fifth of all mediastinal masses. Most grow to large size before causing symptoms. Mediastinal teratoma can appear in any age of the child. Primary symptom is respiratory distress caused by airway compression, followed by feeding problems related to dyspnea, coughing, wheezing and chest pain. Most mediastinal teratomas are mature and benign. Teratomas arise from pluripotent cells and are composed of a wide diversity of tissues originating from three germ layers ectoderm, mesoderm and endoderm. Besides an anterior mediastinal mass, plain chest films can show calcifications. CT Scan is the study of choice to demonstrate the extent of the tumor and its relationship with other structures. As with any other suspected teratoma preoperative alpha fetoprotein and human chorionic gonadotropin markers levels should be obtained. Teratomas are classified as mature, immature and malignant. Mature teratomas are predominantly cystic, while malignant teratomas are mainly solid lesions. Immature teratomas have immature tissue with mature elements. Surgical excision through a median sternotomy is the treatment of choice for mediastinal teratomas. Adjuvant chemotherapy is used in immature and malignant teratoma to increase survival.

F. Ovarian Tumors

Ovarian tumors are uncommon childhood malignancies (1%) characterized by recurrence and resistance to therapy. Aggressive surgery is limited to avoid compromising reproductive capacity and endocrine function. Low incidence and need of multinodal therapy encourages referral to centers dealing with effective cancer therapy. The most common histology is germ cell: dysgerminoma, teratoma, and endodermal sinus tumor. This is followed by the sex-cord stroma tumors with a low incidence of malignancy. They can cause feminization (granulosa-theca cell) and masculinization (androblastoma). Other types are: epithelial (older adolescent), lipid-cell, and gonadoblastoma. Ovarian tumors present with acute abdominal symptoms (pain) from impending rupture or torsion. They also cause painless abdominal enlargement, or hormonal changes. Preop work-up should include: human chorionic gonadotropin (HCG) and alpha-fetoprotein (AFP) levels. Imaging studies: Ultrasound and CT-Scan. The most important prognostic factor in malignant tumors is stage of disease at time of diagnosis. Objectives of surgery are: accurate staging (inspection of peritoneal surfaces and pelvic organs, lymph node evaluation), washing and cytology of peritoneal fluid, tumor removal, and contralateral ovarian biopsy if needed. Chemotherapy consists of: bleomycin, cis-platinum, and vinblastine. Radiotherapy is generally not effective, except in dysgerminoma. Elevation of tumor markers (AFP or HCG) after therapy signals recurrence.



Sertoli-Leydig cell ovarian tumors are rare androgen producing tumors causing masculinization in most girls. A few are nonfunctional tumors. Sertoli-Leydig cell tumors used to be called arrhenoblastoma or androblastomas. One-third of all Sertoli-Leydig cell tumors (SLCT) occur in children. Most SLCT are unilateral. Histologic diagnosis depends on the presence of heterologous endodermal and mesenchymal components. The androgenic effect of the tumor causes accelerated somatic growth and amenorrhea in prepubertal girls. Postpubertal girls develop irregular menstrual cycles, hirsutism and masculinization. Most affected children usually present with a pelvic mass. Testosterone and alpha-fetoprotein produced by the tumor are used as genetic tumor markers. Diagnosis is usually done by ultrasound or CT-Scan in association with the masculinizing clinical picture. Management consists of unilateral salpingo-oophorectomy. Poorly differentiated tumors might need adjuvant chemotherapy and radiotherapy. Prognosis correlates most meaningfully with the stage and degree of differentiation of the tumor. High-stage tumors are all clinically malignant.

G. Thyroid Nodules & Multinodular Goiter

In spite of presenting with advanced, multicentric and larger tumors children have a better survival than adults. Populations at risk: past radiation to head and neck, nuclear waste radiation, MEN II kindred. Clinical presentation is a solitary cervical mass or metastatic lymph node. Diagnostic work‑up should include: sonogram (cystic or solid), thyroid scan (cold or hot), Fine‑needle aspiration cytology (FNA), and Chest‑X‑Ray (lung metastasis 20% at dx). Pathology of tumors: papillary (majority, psammomas bodies), follicular (vascular or capsular invasion), medullary (arise from C‑cells, multicentric, locally invasive), anaplastic (rare, invasive and metastatic).

Management is surgical. Complications of surgery increase with decreasing age of patient: temporary hypoparathyroidism, recurrent nerve injury. Prognostic factors associated to higher mortality are: non‑diploid DNA, psammomas bodies, over 2 cm diameter nodule, and anaplastic histology. Follow‑up for recurrence with serum thyroglobulin level and radioisotope scans. Adjunctive therapy: thyroid suppression and radio‑iodine for lymph nodes and pulmonary metastasis.

Non-toxic multinodular goiter (MNG) refers to multinodular enlargement of the thyroid gland without overt hormone output. MNG is rare in children affecting primordially adolescent kids. The etiology of pediatric MNG appears multifactorial including autoimmune and familial factors (familial form has increased incidence of malignancy). Children presents with asymptomatic progressive nodular enlargement of both lobes of the thyroid gland. Work-up should include neck ultrasonography, thyroid scintigraphy, thyroid hormone levels, assessment of autoantibodies (antimicrosomal, antithyroid), aspiration cytology and histological examination. In populations with iodine deficiency, multinodular goiter is endemic. MNG follows an initial phase of hyperplastic goiter or results from the generation of several individual nodules. Alterations of the stromal and vascular tissues as well as the occurrence of somatic mutations are contributing factors. Histological examination of removed affected glands shows multiple adenomas with areas of epithelial hyperplasia, hemorrhage, and calcification. MNG has an 8% potential for malignant transformation in the form of papillary carcinoma, mostly increased in familial cases, those that have received cervical irradiation and presence of cervical adenopathies. Indications for surgery in non-toxic MNG includes compression symptoms such as painful or difficulty in swallowing, breathing discomfort, suspicion of carcinoma or cosmetic. Total thyroidectomy seems to be the most effective surgical procedure with lower morbidity than subtotal thyroidectomy.

H. Burkitt’s Lymphoma

Burkitt's lymphoma (BL) is a highly malignant tumor first described during the late 50's in African children (jaw), endemic in nature, and composed of undifferentiated lympho‑reticular cells with uniform appearance. The American BL variety is non‑endemic, mostly attacks children between 8‑12 years of age, predominantly (>75%) with abdominal disease such as unexplained mass, pain, or intussusception. The head and neck region follows. The tumor can appear as a localized, diffuse (multifocal, non‑resectable) or metastatic abdominal mass (bone marrow and CNS). It's considered the fastest growing tumor in humans with a doubling time around 12‑24 hrs. Chemotherapy is the primary treatment modality due to its effectiveness in rapidly proliferating cells. The role of surgery is to establish the diagnosis (using open biopsy), stage the tumor, remove localized disease, relieve intestinal obstruction and provide vascular access. Complete resection whenever possible offers the patient improved survival. Is more readily accomplished in patients with localized bowel involvement operated on an emergency basis due to acute abdominal symptoms. The only predictor of event free survival is extent of abdominal disease at diagnosis. Debulking (cytoreductive) procedures increases morbidity and delays initiation of chemotherapy worsening prognosis. Extensive tumors should be managed with minimal procedure and immediate chemotherapy (a/o radiotherapy). Bone marrow and CNS involvement are ominous prognostic signs.

I. Gastrointestinal Stromal Tumor

Gastrointestinal stromal tumor (GIST), previously known as gastric leiomyoblastoma, is an uncommon nonepithelial mesenchymal kit-positive (CD117 antigen) tumor of the gastrointestinal tract. GIST are the most common mesenchymal tumors of the gastrointestinal tract. Cell of origin is the interstitial cell of Cajal. The frequency of malignant GIST is 20-30% of the frequencies of all soft-tissue sarcomas, but small benign tumors often found incidentally during unrelated surgery or autopsy are more common. GIST occurs in children, young adults or on a familial basis. Most involved children are girls with symptoms of abdominal pain and anemia. CT-Scan or MRI suggests the diagnosis. Most GIST appears in the stomach (submucosal mass), followed by the intestine and rarely the colon. Metastasis occurs to the liver. Large tumors (> 5 cm) with high mitotic activity are associated with bad prognosis. Management consists of complete surgical resection with prophylactic omentectomy to reduce the recurrence of GIST. GIST have lower survival rate and more resistance to chemotherapy.

J. Osteochondromas

Osteochondroma is the most common benign bone exostosis found in children. Osteochondroma most frequently arise sporadically and as a solitary lesion, but may also arise associated with hereditary multiple exostosis. Hereditary multiple exostosis is an autosomal dominant disorder in which the clinical hallmark is the growth of bony protuberances from long bones causing a variety of orthopedic deformities. In hereditary multiple osteochondromas the prevalence is one in 50,000 individuals. Ten percent of affected children have no family history of multiple exostosis. Median age at the time of diagnosis is three years. Most cases present with an obvious deformity of the forearm, followed by an inequality in the lengths of the limbs, an angular deformity of the knee, or a deformity of the ankle. Symptomatics complications of osteochondroma consists of pain,  fracture, osseous deformity limiting range of motion, vascular injury, neurological compromise, bursa formation and malignant transformation (chondrosarcoma). MRI is the ideal imaging modality in the diagnostic evaluation of symptomatic complications of osteochondromas and often avoids the need for further imaging. Spontaneous resolution of a solitary osteochondroma is rare. Management of symptomatic osteochondromas is surgical excision. Surgical complications associated with excision consist of peroneal neurapraxias, arterial laceration, compartment syndrome and fibular fracture. The surgical risk for the management of osteochondromas is low.

K. Juvenile Secretory Carcinoma

Carcinoma of the breast in a child is a rare pathologic entity, constitutes less than 1% of all breast lesions in this age group. Juvenile secretory carcinoma is an uncommon malignant tumor that can develop in the breasts of both sexes with a mean age of occurrence at 10 years. It's a slow growing tumor that can recur locally and metastasize to the ipsilateral axillary lymph nodes. Juvenile secretory carcinoma component are devoid of estrogen and progesterone receptors. The child develops a painless mass often near the areola in the breast early in life. The lesion is well demarcated and unencapsulated invading the adjacent tissue. Immunohistochemical staining for alpha lactalbumin is present. When in doubt fine needle aspiration biopsy (cytology) can provide a preoperative diagnosis of the lesion. In all cases, the samples are cellular and feature diffuse, prominent, intracytoplasmic vacuoles and secretion in malignant cells with occasional signet-ring like forms. Management consists of simple mastectomy (wide local excision) with sentinel axillary lymph node biopsy, especially in males cases were metastasis to the axilla are more common. Biological behavior seems to be similarly favorable in both sexes.



L. Vascular Access

Central venous access in children is a necessity for drawing blood, administering blood products and chemotherapeutic agents, and providing parenteral nutrition. Access through the various sites such as the internal and external jugular veins, subclavian and saphenous vein can be plague of complications. Immediate complications at the time of the procedure includes failure to achieve successful access, pleural laceration with pneumothorax development, laceration of the vein with hemothorax, shock, and extravascular placement of the catheter leading to infection, airway compression and pericardial tamponade. Unless you do the procedure fluoroscopically, it is imperative to obtain a chest film immediately after central venous access to confirm adequate position of the catheter and check for the above mentioned complications. Complications associated with long term vascular access include infection (local or systemic bacteremia), occlusion of the catheter, and chronic erosion of the catheter through the wall of the vessel with extravasation. Deep venous thrombosis can occur due to nidus deposition of fibrin. Catheter breakage with embolization is another complication of long standing access.

Implantable central venous catheters constitute a necessity for the management of long term intravenous nutrition and chemotherapy. Implantable central venous access devices placed via the subclavian vein may become obstructed by thrombosis, impingement against a vein wall, or compressed between the clavicle and first rib. Compression of the catheter between the clavicle and first rib is known as pinch-off syndrome (POS). Beside obstruction, pinch-off syndrome can cause fragmentation, fracture or rupture of the catheter causing embolization of the released fragment of tubing. Mechanical friction against the catheter has been well established as the mechanism for most fractures. POS is characterized by intermittent catheter malfunction in conjunction with radiologic evidence of catheter compression. Warning signs of POS include difficulty withdrawing blood samples and resistance to infusion of IV fluids. Catheter transection with migration of the catheter into the heart or pulmonary artery may be accompanied by the sudden onset of chest pain, palpitations, and arrhythmias. Electron microscopic scanning tends to prove that the catheter's rupture is caused by a fatigue process. Treatment of POS is removal of the catheter. If the tip of the catheter has embolized, it can usually be retrieved percutaneously with a transvenous snare. POS can be prevented by using the internal jugular vein for access rather than the subclavian vein.

Hemoports catheters play a vital role in providing continuous central venous access for such therapy as parenteral alimentation, long-term antibiotics and cancer chemotherapy in children and adults. The tip of the hemoport catheter should lie within the superior vena cava or right atrial junction during placement. Placement can be done through the external or internal jugular vein or using the subclavian vein with the port usually lying infraclavicularly in the anterior chest area. Very rarely fragmentation with embolization of the port catheter can occur specially during removal of the port. Incidence of catheter fractures is 0.1%. Fracture is suspected if the catheter offers resistance to removal and/or the length removed is too short. The fragmented retained catheter can cause endocarditis, thrombosis, pulmonary abscess, dysrhythmia or sudden death. Causes of fracture include manufacturing defect, mechanical trauma, excessive hydrostatic pressure when flushing or infusing, material degradation, stress due to constant motion, deposition of fibrin, clot or calcium within the catheter, or pinching between the clavicle and the first rib. The fragmented catheter should be differentiated from a calcified “ghost” cast by CT-Scan. The fragmented catheter can stay within the vascular vessel, or embolized into the right heart or pulmonary arteries. Management should consist of percutaneous endovascular retrieval by an invasive cardiologist or radiologist. 

M. Diaphragmatic Tumors

Tumors arising from the muscle or elements of the diaphragm are very rare in occurrence. The small published series has shown that the incidence is similar between boys and girls along with left or right involvement. Most primary tumors arising from the diaphragm are malignant, with rhabdomyosarcoma the most commonly encountered followed by sarcomas, yolk sac tumors and extraosseous Ewing sarcoma. Lymphangiomas and hemangiomas are the most common benign tumors found in the diaphragm. The clinical presentation in children varies, with predominantly chest symptoms (chest pain, shortness of breath, cough, chest asymmetry or hemothorax). Identifying the site of origin of the tumor to the diaphragm is difficult even after using CT, MRI and ultrasound. Exploratory laparotomy with biopsy is the best tool to assign location to the tumor. Management of primary diaphragmatic tumors encompasses wide local resection with reconstruction, chemotherapy and radiotherapy. To obtain cure, a tumor free resection margin must be obtain initially or after chemotherapy shrinkage of the tumor. Reconstruction of the diaphragm at the time of resection can be accomplished with a muscle flap or prosthetic graft (PTFE or Gore-Tex).

N. Gonadoblastoma

Gonadoblastoma is a sex cord gonadal tumor that contains both germ cell and sex cord stromal elements. It occurs almost exclusively in sexually abnormally individuals with gonadal dysgenesis and Y-containing cells, while other cases occur in children with mixed gonadal dysgenesis (mosaic 45XO/46XY). The combination of the Y chromosome with a dysgenetic gonad is all that is needed for a gonadoblastoma or dysgerminoma to develop. The tumor is usually quite small and calcifications are common. Almost 40% of all gonadoblastomas are bilateral. The germ cell component may outgrow the stromal elements and result in the formation of a dysgerminoma. Most cases will appear in young female adults with history of primary amenorrhea during teenage years and virilization. Management of gonadoblastoma consists of removal of both dysgenetic gonads irrespective of the bilaterality of the lesion. Because these tumors occur in up to 50% of patients with gonadal dysgenesis early bilateral prophylactic gonadectomy should be performed. Gonadoblastomas can exhibit either benign or malignant features, though most cases are benign tumors that have a good prognosis after excision. Gonadectomy can either be done open or laparoscopically. With the presence of malignant germ cell elements, chemotherapy will be needed. Other children at risk to develop gonadoblastoma later in life include those with Turners and androgen insensitivity syndrome.

O. Pancreatic Carcinoma & Frantz Tumor

Tumors of the pancreas can arise from exocrine or endocrine cells. Adenocarcinoma of the pancreas is an extremely rare tumor found during the pediatric age. Most adenocarcinomas of the pancreas are non‑islet cell lesions of ductal origin with more than 70% located in the head of the pancreas. Others are acinar cell carcinomas and nonfunctional islet cell carcinomas. More than half the cases are females with a mean age of nine years (range three months to 18 years). As in adults this is a very aggressive malignant neoplasm with early metastatic spread to lymph nodes and liver. While the majority of pancreatic tumors are exocrine lesions of ductal origin, acinar cell tumors are more commonly observed in children and associated with a better prognosis. Children with pancreatic ductal carcinoma presents with abdominal and back pain, vomiting, obstructive jaundice, a palpable mass and weight loss. Diagnostic imaging should consist of ultrasound, CT‑Scan and MRI to look for chances of surgical resectability. Genetic markers such as CEA, C19‑9, and alpha fetoprotein should be obtained. Whenever feasible and in the event of no metastatic disease management should consist of surgical resection of the tumor. Body and tail tumors can be dealt with distal pancreatectomy, while head of pancreas tumors will need pancreaticoduodenectomy (Whipple procedure). The response rate with chemotherapy and/or radiotherapy is very poor. The prognosis with metastatic disease is dismal.

Papillary cystic tumor of the pancreas, also known as Frantz tumor (FT) since 1959, occurs predominantly in girls and young women (mean age 21 years). Abdominal pain and a slowly growing incidentally found epigastric mass is the most common complains, associated at times with weight loss, anorexia and vomiting. FT is well-encapsulated, shows solid and hemorrhagic patterns, contain PAS-positive cytoplasmic or prozymogen granules as seen in acinar cell tumors and behaves as a low-grade malignancy. CT scans suggest the diagnosis (thick capsule, calcifications, mixed solid and cystic patterns, grows toward the outside of the pancreas). Differential diagnosis includes traumatic pseudocysts, serous and mucinous cystadenomas of the pancreas. Immunohistochemically the tumor is positive for alpha-1-antitrypsin while negative for insulin and glucagon. Complete removal is the treatment of choice for tumor arising in any part of the pancreas. FT is frequently amenable to local resection and has a good long-term survival rate after excision. Metastasis (liver) or local recurrence occurs in 10% of cases. Older age at diagnosis or recurrence disease increases the malignant biological behavior of the tumor. Radiotherapy and, or chemotherapy are of no use for its treatment.






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