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Diagnosis may include a fluorescence in situ hybridization (FISH) test, computed tomography urography (CTU), magnetic resonance urography (MRU), intravenous pyelography (IVP) x-ray, ureteroscopy, or biopsy.
Diagnosis is established by transurethral biopsy. Types of urethral cancer include transitional cell carcinoma, squamous cell carcinoma, adenocarcinoma, and melanoma.
Intraductal papillary mucinous neoplasms can come to clinical attention in a variety of different ways. The most common symptoms include abdominal pain, nausea and vomiting. The most common signs patients have when they come to medical attention include jaundice (a yellowing of the skin and eyes caused by obstruction of the bile duct), weight loss, and acute pancreatitis. These signs and symptoms are not specific for an intraductal papillary mucinous neoplasm, making it more difficult to establish a diagnosis. Doctors will therefore often order additional tests.
Once a doctor has reason to believe that a patient may have an intraductal papillary mucinous neoplasm, he or she can confirm that suspicion using one of a number of imaging techniques. These include computerized tomography (CT), endoscopic ultrasound (EUS), and magnetic resonance cholangiopancreatography (MRCP). These tests will reveal dilatation of the pancreatic duct or one of the branches of the pancreatic duct. In some cases a fine needle aspiration (FNA) biopsy can be obtained to confirm the diagnosis. Fine needle aspiration biopsy can be performed through an endoscope at the time of endoscopic ultrasound, or it can be performed through the skin using a needle guided by ultrasound or CT scanning.
IPMN forms cysts (small cavities or spaces) in the pancreas. These cysts are visible in CT scans (X-ray computed tomography). However, many pancreatic cysts are benign (see Pancreatic disease).
A growing number of patients are now being diagnosed before they develop symptoms (asymptomatic patients). In these cases, the lesion in the pancreas is discovered accidentally (by chance) when the patient is being scanned (i.e. undergoing an ultrasound, CT or MRI scan) for another reason. Up to 6% of patients undergoing pancreatic resection did so for treatment of incidental IPMNs.
In 2011, scientists at Johns Hopkins reported that they have developed a gene-based test that can be used to distinguish harmless from precancerous pancreatic cysts. The test may eventually help patients with harmless cysts avoid needless surgery. Bert Vogelstein and his colleagues discovered that almost all of the precancerous cysts (intraductal papillary mucinous neoplasms) of the pancreas have mutations in the KRAS and/or the GNAS gene. The researchers then tested a total of 132 intraductal papillary mucinous neoplasms for mutations in KRAS and GNAS. Nearly all (127) had mutations in GNAS, KRAS or both. Next, the investigators tested harmless cysts such as serous cystadenomas, and the harmless cysts did not have GNAS or KRAS mutations. Larger numbers of patients must be studied before the gene-based test can be widely offered.
Serous cystic neoplasms can come to clinical attention in a variety of ways. The most common symptoms are very non-specific and include abdominal pain, nausea and vomiting. In contrast to many of the other tumors of the pancreas, patients rarely develop jaundice (a yellowing of the skin and eyes caused by obstruction of the bile duct), or weight loss. These signs and symptoms are not specific for a serous cystic neoplasm, making it more difficult to establish a diagnosis. Doctors will therefore often order additional tests.
Once a doctor has reason to believe that a patient may have serous cystic neoplasm, he or she can confirm that suspicion using one of a number of imaging techniques. These include computerized tomography (CT), endoscopic ultrasound (EUS), and magnetic resonance cholangiopancreatography (MRCP). These tests will reveal a cystic mass within the pancreas. The cysts do not communicate with the larger pancreatic ducts. In some cases a fine needle aspiration (FNA) biopsy can be obtained to confirm the diagnosis. Fine needle aspiration biopsy can be performed through an endoscope at the time of endoscopic ultrasound, or it can be performed through the skin using a needle guided by ultrasound or CT scanning.
A growing number of patients are now being diagnosed before they develop symptoms (asymptomatic patients). In these cases, the lesion in the pancreas is discovered accidentally (by chance) when the patient is being scanned (x-rayed) for another reason.
Urethral diverticulum is often an incidental finding. It can be diagnosed using magnetic resonance imaging and/or micturating cystourethrography. Other studies that can be used to diagnose urethral diverticulum include intravenous urography, urethroscopy, and/or ultrasound. Conditions that should be distinguished from urethral diverticulum in a differential diagnosis include overactive bladder, Gartner's duct cyst, Gartner's duct abscess, ectopic caeco-ureterocele, interstitial cystitis, pelvic inflammatory disease, endometriosis, and cancer.
Treatment methods include surgery, chemotherapy, radiation therapy and medication.
Surgery is the most common treatment for cancer of the urethra. One of the following types of surgery may be done: Open excision, Electro-resection with flash, Laser surgery, Cystourethrectomy, Cystoprostatectomy, Anterior body cavity, or Incomplete or basic penectomy surgery.
Chemotherapy is sometimes used to destroy urethral cancer cells. It is a systemic urethral cancer treatment (i.e., destroys urethral cancer cells throughout the body) that is administered orally or intravenously. Medications are often used in combination to destroy urethral cancer that has metastasized. Commonly used drugs include cisplatin, vincristine, and methotrexate.
Side effects include anemia (causing fatigue, weakness), nausea and vomiting, loss of appetite, hair loss, mouth sores, increased risk for infection, shortness of breath, or excessive bleeding and bruising.
In boys, history and physical exam is adequate to make the diagnosis. In girls, VCUG (voiding cystourethrogram) is usually diagnostic. Other tests may include:
- Urine analysis
- Urine culture
- CBC, basic metabolic panel
- Renal and bladder ultrasound
The treatment of choice for main-duct IPMNs is resection due to approximately 50% chance of malignancy. Side-branch IPMNs are occasionally monitored with regular CT or MRIs, but most are eventually resected, with a 30% rate of malignancy in these resected tumors. Survival 5 years after resection of an IPMN without malignancy is approximately 80%, 85% with malignancy but no lymph node spread and 0% with malignancy spreading to lymph nodes. Surgery can include the removal of the head of the pancreas (a pancreaticoduodenectomy), removal of the body and tail of the pancreas (a distal pancreatectomy), or rarely removal of the entire pancreas (a total pancreatectomy). In selected cases the surgery can be performed using minimally invasive techniques such as laparoscopy or robotic surgery. A study using Surveillance, Epidemiology, and End Result Registry (SEER) data suggested that increased lymph node counts harvested during the surgery were associated with better survival in invasive IPMN patients.
The primary treatment for urethral diverticulum is surgical. The surgery is conducted transvaginally, usually when there is no acute inflammation to better aid dissection of the delicate tissues.
Following urethroplasty, patients should be monitored for a minimum of 1 year, since the vast majority of recurrences occur within 1 year.
Because of the high rate of recurrence following dilation and other endoscopic approaches, the provider must maintain a high index of suspicion for recurrence when the patient presents with obstructive voiding symptoms or urinary tract infection.
Urethroplasty refers to any open reconstruction of the urethra. Success rates range from 85% to 95% and depend on a variety of clinical factors, such as stricture as the cause, length, location, and caliber. Urethroplasty can be performed safely on men of all ages.
In the posterior urethra, anastomotic urethroplasty (with or without preservation of bulbar arteries) is typically performed after removing scar tissue.
In the bulbar urethra, the most common types of urethroplasty are anastomotic (with or without preservation of corpus spongiosum and bulbar arteries) and substitution with buccal mucosa graft, full-thickness skin graft, or split thickness skin graft. These are nearly always done in a single setting (or stage).
In the penile urethra, anastomotic urethroplasties are rare because they can lead to chordee (penile curvature due to a shortened urethra). Instead, most penile urethroplasties are substitution procedures utilizing buccal mucosa graft, full-thickness skin graft, or split thickness skin graft. These can be done in one or more setting, depending on stricture location, severity, cause and patient or surgeon preference.
These lesions rarely require surgery unless they are symptomatic or the diagnosis is in question. Since these lesions do not have malignant potential, long-term observation is unnecessary. Surgery can include the removal of the head of the pancreas (a pancreaticoduodenectomy), removal of the body and tail of the pancreas (a distal pancreatectomy), or rarely removal of the entire pancreas (a total pancreatectomy). In selected cases the surgery can be performed using minimally invasive techniques such as laparoscopy.
Abdominal ultrasound is of some benefit, but not diagnostic. Features that suggest posterior urethral valves are bilateral hydronephrosis, a thickened bladder wall with thickened smooth muscle trabeculations, and bladder diverticula.
Voiding cystourethrogram (VCUG) is more specific for the diagnosis. Normal "plicae circularis" are variable in appearance and often not seen on normal VCUGs. PUV on voiding cystourethrogram is characterized by an abrupt tapering of urethral caliber near the verumontanum, with the specific level depending on the developmental variant. Vesicoureteral reflux is also seen in over 50% of cases. Very often the posterior urethra maybe dilated thus making the abrupt narrowing more obvious. the bladder wall may show trabeculations or sacculations or even diverticuli.
Diagnosis can also be made by cystoscopy, where a small camera is inserted into the urethra for direct visualization of the posteriorly positioned valve. A limitation of this technique is that posterior valve tissue is translucent and can be pushed against the wall of the urethra by inflowing irrigation fluid, making it difficult to visualize. Cystoscopy may also demonstrate the bladder changes.
Centers in Europe and Japan have also had excellent results with cystosonography, although it has not been approved for use in the United States yet.
Penile color duplex doppler ultrasound can help with preoperative planning to minimize bulbar necrosis.
In females, meatal stenosis can usually be treated in the physician's office using local anesthesia to numb the area and dilating (widening) the urethral opening with special instruments.
In boys, it is treated by a second surgical procedure called meatotomy in which the meatus is crushed with a straight mosquito hemostat and then divided with fine-tipped scissors. Recently, home-dilatation has been shown to be a successful treatment for most boys.
Anterior urethral cancer is a disease in which malignant cancer cells are found in the part of the urethra that is closest to the outside of the body.
The definitive diagnosis is by histologic analysis, i.e. and examination under the microscope.
Under the microscope, OKCs vaguely resemble keratinized squamous epithelium; however, they lack rete ridges and often have an artifactual separation from their basement membrane.
On a CT scan, The radiodensity of a keratocystic odontogenic tumour is about 30 Hounsfield units, which is about the same as ameloblastomas. Yet, ameloblastomas show more bone expansion and seldom show high density areas.
A Gartner's duct cyst (sometimes incorrectly referred to as "vaginal inclusion cyst") is a benign vaginal cystic lesion that arises from the Gartner's duct, which is a vestigial remnant of the mesonephric duct (wolffian duct) in females. They are typically small asymptomatic cysts that occur along the lateral walls of the vagina, following the course of the duct. They can present in adolescence with painful menstruation (Dysmenorrhea) or difficulty inserting a tampon. They can also enlarge to substantial proportions and be mistaken for urethral diverticulum or other structures.
There is a small association between Gartner's duct cysts and metanephric urinary anomalies, such as ectopic ureter & ipsilateral renal hypoplasia. Because of this, imaging is recommended before excision.
Radiologically
- Odontogenic Myxoma
- Ameloblastoma
- Central Giant Cell Granuloma
- Adenomatoid odontogenic tumor
Histologically
- Orthokeratocyst
- Radicular cyst (particularly if the OKC is very inflamed)
- Unicystic ameloblastoma
Imaging studies, such as an intravenous urogram (IVU), renal ultrasonography, CT or MRI, are also important investigations in determining the presence and/ or cause of hydronephrosis. Whilst ultrasound allows for visualisation of the ureters and kidneys (and determine the presence of hydronephrosis and / or hydroureter), an IVU is useful for assessing the anatomical location of the obstruction. Antegrade or retrograde pyelography will show similar findings to an IVU but offer a therapeutic option as well. Real-time ultrasounds and Doppler ultrasound tests in association with vascular resistance testing helps determine how a given obstruction is effecting urinary functionality in hydronephrotic patients.
In determining the cause of hydronephrosis, it is important to rule out urinary obstruction. One way to do this is to test the kidney function. This can be done by, for instance, a diuretic intravenous pyelogram, in which the urinary system is observed radiographically after administration of a diuretic, such as 5% mannitol, and an intravenous iodine contrast. The location of obstruction can be determined with a Whittaker (or pressure perfusion) test, wherein the collecting system of the kidney is accessed percutaneously, and the liquid is introduced at high pressure and constant rate of 10ml/min while measuring the pressure within the renal pelvis. A rise in pressure above 22 cm HO suggests that the urinary collection system is obstructed. When arriving at this pressure measurement, bladder pressure is subtracted from the initial reading of internal pressure. (The test was first described by Whittaker in 1973 to test the hypothesis that patients' whose hydronephrosis persists after the posterior urethral valves have been ablated usually have ureters that are not obstructed, even though they may be dilated.)
Kay recommends that a neonate born with untreated in utero hydronephrosis receive a renal ultrasound within two days of birth. A renal pelvis greater than 12mm in a neonate is considered abnormal and suggests significant dilation and possible abnormalities such as obstruction or morphological abnormalities in the urinary tract.
The choice of imaging depends on the clinical presentation (history, symptoms and examination findings). In the case of renal colic (one sided loin pain usually accompanied by a trace of blood in the urine) the initial investigation is usually a spiral or helical CT scan. This has the advantage of showing whether there is any obstruction of flow of urine causing hydronephrosis as well as demonstrating the function of the other kidney. Many stones are not visible on plain X-ray or IVU but 99% of stones are visible on CT and therefore CT is becoming a common choice of initial investigation. CT is not used however, when there is a reason to avoid radiation exposure, e.g. in pregnancy.
For incidentally detected prenatal hydronephrosis, the first study to obtain is a postnatal renal ultrasound, since as noted, many cases of prenatal hydronephrosis resolve spontaneously. This is generally done within the first few days after birth, although there is some risk that obtaining an imaging study this early may miss some cases of mild hydronephrosis due to the relative oliguria of a newborn. Thus, some experts recommend obtaining a follow up ultrasound at 4–6 weeks to reduce the false-negative rate of the initial ultrasound. A voiding cystourethrogram (VCUG) is also typically obtained to exclude the possibility of vesicoureteral reflux or anatomical abnormalities such as posterior urethral valves. Finally, if hydronephrosis is significant and obstruction is suspected, such as a ureteropelvic junction (UPJ) or ureterovesical junction (UVJ) obstruction, a nuclear imaging study such as a MAG-3 scan is warranted.
The treatment is simple excision and exclusion of a malignant neoplasm.
In a small minority of cases of urethral syndrome, treatment with antibiotics is effective, which indicates that in some cases it may be caused by bacterial infection which does not show up in either urinalysis or urine culture. For chronic urethral syndrome, a long term, low-dose antibiotic treatment is given on a continuous basis or after intercourse each time if intercourse appears to trigger symptoms.
As low oestrogen may also be considered a source for urethral syndrome, hormone replacement therapy, and oral contraceptive pill (birth-control pills) containing oestrogen are also used to treat the symptoms of this condition in women.
Diagnosis is based on results of bladder catheterization, ultrasonography, CT scan, cystourethroscopy, or pyelography, depending on the level of obstruction.
If suspected antenatally, a consultation with a paediatric surgeon/ paediatric urologist maybe indicated to evaluate the risk and consider treatment options.
Treatment is by endoscopic valve ablation. Fetal surgery is a high risk procedure reserved for cases with severe oligohydramnios, to try to limit the associated lung underdevelopment, or pulmonary hypoplasia, that is seen at birth in these patients. The risks of fetal surgery are significant and include limb entrapment, abdominal injury, and fetal or maternal death. Specific procedures for "in utero" intervention include infusions of amniotic fluid, serial bladder aspiration, and creating a connection between the amniotic sac and the fetal bladder, or vesicoamniotic shunt.
There are three specific endoscopic treatments of posterior urethral valves:
- Vesicostomy followed by valve ablation - a stoma, or hole, is made in the urinary bladder, also known as "low diversion", after which the valve is ablated and the stoma is closed.
- Pyelostomy followed by valve ablation - stoma is made in the pelvis of the kidney as a slightly "high diversion", after which the valve is ablated and the stoma is closed
- Primary (transurethral) valve ablation - the valve is removed through the urethra without creation of a stoma
The standard treatment is primary (transurethral) ablation of the valves. Urinary diversion is used in selected cases, and its benefit is disputed.
Following surgery, the follow-up in patients with posterior urethral valve syndrome is long term, and often requires a multidisciplinary effort between paediatric surgeons/ paediatric urologists, pulmonologists, neonatologists, radiologists and the family of the patient. Care must be taken to promote proper bladder compliance and renal function, as well as to monitor and treat the significant lung underdevelopment that can accompany the disorder. Definitive treatment may also be indicated for the vesico-ureteral reflux.