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Definition

Wilms tumor is the most common primary malignant renal tumor of childhood and is the paradigm for multimodal management of a pediatric malignant solid tumor.

Epidemiology

The incidence of Wilms tumor is 10 cases per million among white children younger than 15 years, and the male to female ratio is low. The incidence is approximately three times higher for blacks in the United States and Africa than for eastern Asians.

Clinical Manifestation

• Abdominal swelling or abdominal mass (most common complain).
• Abdominal mass
• Gross hematuria
• Fever
• Hypertension (about 25% of cases).

Differential Diagnosis

• Splenomegaly
• Neuroblastoma (often arises in the celiac axis or extends across the midline because of lymph node involvement).

Imaging Studies

• Ultrasonography
   The patency of the inferior vena cava.
• CT Scans of the abdomen with contrast
  To evaluate the nature and extent of the mass, may suggest apparent extension of the tumor into adjacent      structures, such as the liver, spleen, or colon.
• Plain chest radiographs, CT scans of chest
  To determine whether pulmonary metastasis is present.
• Brain CT scans or MRI
  For all children with clear cell sarcoma of the kidney or rhabdoid tumor of the kidney

Staging


Treatment

Surgery
• Surgical removal of the primary tumor remains the cornerstone of Wilms tumor therapy.
• Assessment of tumor spread at surgery is essential for accurate staging and for subsequent determination of the need for radiation therapy and administration of the appropriate chemotherapeutic regimen. Every effort must be made to remove the tumor without causing spread or spill.

Radiotherapy
• The National Wilms Tumor Studies have shown that patients with stage I and II tumors and favorable histologic findings who receive vincristine and actinomycin D do not need postoperative irradiation.

Chemotherapy
According to National Wilms Tumor Study Group findings, the chemotherapy regimens recommended for children with favorable histologic findings of Wilms tumor depend on tumor stage:
• Stage I or II, vincristine and actinomycin D for 18 weeks
• Stage III or IV, a combination of vincristine, actinomycin D, and doxorubicin for 21 weeks.

Prognosis

The most important determinant of prognosis :
• Tumor size
• Age of the patient
• Presence of lymph node metastasis
• Local features of the tumor, such as capsular or vascular invasion.

Definition

The term triage, derived from the French word meaning “to sort,” in its military application involves prioritizing victims into categories based on their severity of injury, likelihood of survival, and urgency of care.

The goal of civilian prehospital triage is to identify high-risk injured patients who would benefit from the resources available in a trauma center.

Goal

The ideal tool to accomplish these two divergent tasks does not exist. Assessment must be made quickly, often under difficult conditions with limited resources, and current schemes are of limited accuracy.

Although it is easy to identify patients with severe injuries based on abnormal physiology, a more difficult problem is identification of high-risk patients whose initial physiologic status is normal.

Perhaps the most useful currently available system is that advocated by the Committee on Trauma of the American College of Surgeons, which assesses four components simultaneously:

1. Physiologic response

2. Injury anatomy

3. Injury biomechanics

4. Comorbid factors.

The goal of a trauma system is to prevent unnecessary death, and thus a certain degree of over-triage is acceptable and even desirable.

Under-triage, however, is always to be avoided because the benefits of trauma center care are withheld from a patient who is thus misclassified. Many studies have tried to determine and adjust the optimal ratio of under- and over-triage. Conventional wisdom suggests that a 50% over-triage rate may be required to minimize under-triage.

Triage can take on differing forms as the situation demands. As medical care resources become limited, alternative triage schemes may be used so that the greatest number of patients may be treated.

Such schemes may be seen in situations of multiple or mass casualties. In these cases the “most good is applied to the greatest number of patients.” This is different from our present triage scheme, whereby the most seriously injured patient receives the majority of the medical care while the less seriously injured wait for care.

Classification

The military uses a triage scheme in which patients are classified for transport as immediate, delayed, or expectant.

The method of triage widely used by municipalities is the START triage scheme, which stands for simple triage and rapid treatment. This is accomplished by color tagging of patients.

· The color red is first priority and signifies a critical patient.

· Yellow (urgent) is second priority.

· Green (minor) is a third-priority patient.

· Black represents expectant or dead patients.

The initial triage assessment components include the ability of the patient to :

· Ambulate

· Respiratory function

· Systemic perfusion

· Level of consciousness.

Patients are classified into transport categories on the basis of these assessments.

Definition

Cysts within the breast are fluid-filled, epithelium-lined cavities that may vary in size from microscopic to large, palpable masses containing as much as 20 to 30 mL of fluid.

Clinical Manifestation

· A palpable cyst develops in at least 1 in every 14 women, and 50% of cysts are multiple or recurrent. The pathogenesis of cyst formation is not well understood. However, cysts appear to arise from destruction and dilation of lobules and terminal ductules.

· Cysts are influenced by ovarian hormones, a fact that explains their variation with the menstrual cycle. Most cysts occur in women older than 35. The incidence of cyst development steadily increases until menopause and sharply declines thereafter. New cyst formation in older women is generally associated with exogenous hormone replacement.

Laboratory Findings

· A palpable mass can be confirmed to be a cyst by aspiration or ultrasound. Cyst fluid can be straw colored, opaque, or dark green and may contain flecks of debris. Given the low risk for malignancy within a cyst, if the palpable mass disappears completely after aspiration and the cyst contents are not grossly bloody, the fluid need not be sent for cytologic analysis.

· If the cyst recurs multiple times (more than two times is a reasonable rule), cytology is justified.

· Microscopic studies have shown that fibrosis at or near the lobule, combined with continued secretion, results in unfolding of the lobule and expansion of an epithelium-lined cavity containing fluid.

Treatment

· Aspiration

· Surgery

Surgical removal of a cyst is usually indicated if the cytologic findings are suspicious or the cyst recurs multiple times.

Pathophysiology

Diagnosis
History

Physical Examination

• Patients with acute appendicitis typically look ill and are lying still in bed.

• Low-grade fever is common (∼38°C).

• The exact location of the tenderness is directly over the appendix, which is most commonly at McBurney's point (located one third of the distance along a line drawn from the anterior superior iliac spine to the umbilicus).

• Peritoneal irritation can be elicited on physical examination by the findings of voluntary and involuntary guarding, percussion, or rebound tenderness. Any movement, including coughing (Dunphy's sign), may cause increased pain.

• Other findings may include pain in the right lower quadrant during palpation of the left lower quadrant (Rovsing's sign), pain on internal rotation of the hip (obturator sign, suggesting a pelvic appendix), and pain on extension of the right hip (iliopsoas sign, typical of a retrocecal appendix).

• Rectal and pelvic examinations are most likely to be negative. However, if the appendix is located within the pelvis, tenderness on abdominal examination may be minimal, whereas anterior tenderness may be elicited during rectal examination as the pelvic peritoneum is manipulated. Pelvic examination with cervical motion may also produce tenderness in this setting.

• Abdominal pain becomes intense and more diffuse, and abdominal muscular spasm increases, producing rigidity.

• The heart rate rises, with an elevation of temperature above 39°C.

• The patient may appear ill and require a brief period of fluid resuscitation and antibiotics before the induction of anesthesia.

• Occasionally, pain may improve somewhat after rupture of the appendix, although a true pain-free interval is uncommon.

• The white blood cell count is elevated with more than 75% neutrophils in most patients. A completely normal leukocyte count and differential is found in about 10% of patients with acute appendicitis.

• A high white blood cell count (>20,000/mL) suggests complicated appendicitis with either gangrene or perforation. A

• Urinalysis can also be helpful in excluding pyelonephritis or nephrolithiasis.

• Other blood tests are generally not helpful and are not indicated in the patient with suspected appendicitis.

Radiography
Barium Enema

• Failure of the appendix to fill during a barium enema has been associated with appendicitis, but this finding lacks both sensitivity and specificity because up to 20% of normal appendices do not fill.

Ultrasonography

• Ultrasonography has a sensitivity of about 85% and a specificity of more than 90% for the diagnosis of acute appendicitis.
• Ultrasonography has the advantages of being a noninvasive modality requiring no patient preparation that also avoids exposure to ionizing radiation.

CT-Scan

• Computed tomography (CT) is commonly used in the evaluation of adult patients with suspected acute appendicitis. CT Scan has a sensitivity of about 90% and a specificity of 80% to 90% for the diagnosis of acute appendicitis among patients with abdominal pain.

• Classic findings include a distended appendix greater than 7 mm in diameter and circumferential wall thickening, which may give the appearance of a halo or target.

• As inflammation progresses, one may see periappendiceal fat stranding, edema, peritoneal fluid, phlegmon, or a periappendiceal abscess.

Differential Diagnoses

• Infants : pyloric stenosis.
• Preschool-aged children : Intussusception, Meckel's diverticulitis, and acute gastroenteritis.
• School-aged children : Gastroenteritis, inflammatory bowel disease, constipation
• Adults : pyelonephritis, colitis, and diverticulitis.
• Women : pelvic inflammatory disease (PID), tubo-ovarian abscess, ruptured ovarian cyst or ovarian torsion, and ectopic pregnancy.

Treatment
Most patients with acute appendicitis are managed by prompt surgical removal of the appendix. A brief period of resuscitation is usually sufficient to ensure the safe induction of general anesthesia. Preoperative antibiotics cover aerobic and anaerobic colonic flora. For patients with nonperforated appendicitis, a single preoperative dose of antibiotics reduces postoperative wound infections and intra-abdominal abscess formation. Postoperative oral antibiotics do not further reduce the incidence of infectious complications in these patients. For patients with perforated or gangrenous appendicitis, we continue postoperative intravenous antibiotics until the patient is afebrile.

Open appendectomy
Open appendectomy is usually easily performed through a transverse right lower quadrant incision (Davis-Rockey) or an oblique incision (McArthur-McBurney).

Laparoscopic appendectomy
Laparoscopic appendectomy offers the advantage of diagnostic laparoscopy combined with the potential for shorter recovery and incisions that are less conspicuous.