Inverted papillomas are definitively diagnosed by histologic examination. However, Magnetic Resonanace Imaging (MRI) may show a characteristic feature described as a Convoluted Cerebriform Pattern (CCP). A retrospective study published in the American Journal of Neuroradiology concluded that identification of CCP by MRI in a patient with a nasal tumor made the diagnosis of Inverted papilloma quite likely. The study reported the sensitivity and specificity to be 100% and 87% respectively. CCP can be associated with other malignant tumors as well.

An inverted papilloma is a type of tumor in which surface epithelial cells grow downward into the underlying supportive tissue. It may occur in the nose and/or sinuses or in the urinary tract (bladder, renal pelvis, ureter, urethra). When it occurs in the nose or sinuses, it may cause symptoms similar to those caused by sinusitis, such as nasal congestion. When it occurs in the urinary tract, it may cause blood in the urine.

A urethral caruncle is a benign cutaneous condition characterized by distal urethral lesions that are most commonly found in post-menopausal women. They appear red, and can be various sizes. They can have the appearance of a tumor. These epidermal growths are found around the posterior portion of the urethral meatus. They can bleed and occasionally dysuria and dyspareunia. The caruncles can be removed by surgery, electric cauterization and then with suture repair. Pathologiy studies are necessary to distinguish carcinoma of the urethra from urethral caruncles. Caruncles can grow back in some instances. Urethral caruncles can accompany the skin changes related to lowered estrogen levels. They can become a source of chronic hematuria, infection, and urethritis.

A benign papillomatous tumor is derived from epithelium, with cauliflower-like projections that arise from the mucosal surface.

It may appear white or normal colored. It may be pedunculated or sessile. The average size is between 1–5 cm.

Neither sex is significantly more likely to develop them. The most common site is the palate-uvula area followed by tongue and lips. Durations range from weeks to 10 years.

A squamous cell papilloma is a generally benign papilloma that arises from the stratified squamous epithelium of the skin, lip, oral cavity, tongue, pharynx, larynx, esophagus, cervix, vagina or anal canal. Squamous cell papillomas are a result of infection with human papillomavirus (HPV).

Squamous cell papilloma of the mouth or throat is generally diagnosed in people between the ages of 30 and 50, and is normally found on the inside of the cheek, on the tongue, or inside of lips. Oral papillomas are usually painless, and not treated unless they interfere with eating or are causing pain. They do not generally mutate to cancerous growths, nor do they normally grow or spread. Oral papillomas are most usually a result of the infection with types HPV-6 and HPV-11.

A papilloma (plural papillomas or papillomata) ("" + "") is a benign epithelial tumor growing exophytically (outwardly projecting) in nipple-like and often finger-like fronds. In this context refers to the projection created by the tumor, not a tumor on an already existing papilla (such as the nipple).

When used without context, it frequently refers to infections (squamous cell papilloma) caused by human papillomavirus (HPV), such as warts. Human papillomavirus infection is a major cause of cervical cancer, although most HPV infections do not cause cancer. There are, however, a number of other conditions that cause papilloma, as well as many cases in which there is no known cause.

Symptoms vary between individuals and can be dependent upon the stage of growth of the carcinoma. Presence of the carcinoma can lead to be asymptomatic blood in the urine (hematuria), Hematuria can be visible or detected microscopically. Visible hematuria is when urine appears red or brown and can be seen with the naked eye. Other symptoms are not specific. Other inflammatory conditions that affect the bladder and kidney can create similar symptoms. Early detection facilitates curing the disease. Other symptoms can involve:

- pain or burning on urination

- the sensation of not being able to completely empty the bladder

- the sensation of needing to urinate more often or more frequently than normal

These symptoms are general and also indicate less serious problems.

Urethral diverticula are often asymptomatic and symptoms that are present tend to be nonspecific. They can co-occur with cancer, in approximately 6-9% of cases, most commonly adenocarcinoma, but also including squamous cell carcinoma and transitional cell carcinoma. Approximately 10% of cases co-occur with kidney stones.

There are 2 types of urethral diverticulums. Congenital and acquired. In infancy usually the urethral diverticulum is congenital but in rare instances acquired urethral diverticulum can be seen in infancy specially following traumatic catheterization.

Common symptoms of urethral diverticulum include incontinence, urinary frequency and urgency, pain during sex, and pain during urination. Other symptoms include pain localized to the urethra or pelvis and frequent urinary tract infection.

When urethral diverticulum becomes severe, a painful mass can sometimes be felt inside the introitus of the vagina, which can discharge pus. If the mass is hard or bleeds, complications like cancer or kidney stones may be present.

Nipple adenomas may be felt as a lump under the nipple or areola. They may come to attention because of nipple pain, ulceration, swelling or discharge.

Signs of the tumor resulting from increased intracranial pressure are present in 91% of patients, with vomiting, homonymous visual field defects and headache being the most common symptoms.

Other symptoms are ear ringing and dizziness.

Ectopic ureter (or ureteral ectopia) is a medical condition where the ureter, rather than terminating at the urinary bladder, terminates at a different site. In males this site is usually the urethra, in females this is usually the urethra or vagina. It can be associated with renal dysplasia, frequent urinary tract infections, and urinary incontinence (usually continuous drip incontinence). Ectopic ureters are found in 1 of every 2000–4000 patients, and can be difficult to diagnose, but are most often seen on CT scans.

Ectopic ureter is commonly a result of a duplicated renal collecting system, a duplex kidney with 2 ureters. In this case, usually one ureter drains correctly to the bladder, with the duplicated ureter presenting as ectopic.

Heck's disease (also known as focal or multifocal epithelial hyperplasia) is an asymptomatic, benign neoplastic condition characterized by multiple white to pinkish papules that occur diffusely in the oral cavity. Can present with slightly pale, smooth or roughened surface morphology. It is caused by the human papilloma virus types 13 and 32. It exhibits surface cells with vacuolated cytoplasm around irregular, pyknotic nuclei and occasional cells with mitosis-like changes within otherwise mature and well-differentiated epithelium. A distinguishing histologic feature is elongated rete ridges resembling Bronze Age axe with mitosoid bodies present. It was first identified in the Aboriginal population.

Over time, they will spontaneously regress without treatment. Possible treatment may be excisional biopsy for lesions of functional or aesthetic concern.

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.

Symptoms that may be caused by urethral cancer include:

Bleeding from the urethra or blood in the urine,

Weak or interrupted flow of urine,

Urination occurs often, painful urination, inability to pass urine,

A lump or thickness in the perineum or penis,

Discharge from the urethra,

Enlarged lymph nodes or pain in the groin or vaginal area.

Symptoms of polyps include nasal congestion, sinusitis, loss of smell, thick nasal discharge, facial pressure, nasal speech, and mouth breathing. Recurrent sinusitis can result from polyps. Long-term, nasal polyps can cause destruction of the nasal bones and widening of the nose.

As polyps grow larger, they eventually prolapse into the nasal cavity resulting in symptoms. The most prominent symptoms of nasal polyps result blockage of the nasal passage.

People with nasal polyps due to aspirin intolerance often have symptoms known as Samter's triad, which consists of asthma worse with aspirin, a skin rash caused by aspirin, and chronic nasal polyps.

Where a urethrocele causes difficulty in urinating, this can lead to cystitis.

There are often no symptoms associated with a urethrocele. When present, symptoms include stress incontinence, increased urinary frequency, and urinary retention (difficulty in emptying the bladder). Pain during sexual intercourse may also occur.

The hallmark sign of urethral stricture is a weak urinary stream. Other symptoms include:

- Splaying of the urinary stream

- Urinary frequency

- Urinary urgency

- Straining to urinate

- Pain during urination

- Urinary tract infection

- Prostatitis

- Inability to completely empty the bladder.

Some patients with severe urethral strictures are completely unable to urinate. This is referred to as acute urinary retention, and is a medical emergency. Hydronephrosis and renal failure may also occur.

Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns. A posterior urethral valve is an obstructing membrane in the posterior male urethra as a result of abnormal "in utero" development. It is the most common cause of bladder outlet obstruction in male newborns. The disorder varies in degree, with mild cases presenting late due to milder symptoms. More severe cases can have renal and respiratory failure from lung underdevelopment as result of low amniotic fluid volumes, requiring intensive care and close monitoring. It occurs in about one in 8000 babies.

A urethral diverticulum is a condition where the urethra or the periurethral glands push into the connective tissue layers (fascia) that surround it.

Bulbar urethral necrosis is a problem that can occur after a pelvic fracture associated urethral distraction defect (PFUDD).

Prenatally diagnosed hydronephrosis (fluid-filled kidneys) suggest post-natal follow-up examination.

The strongest neo-natal presentation is urinary tract infection. A hydronephrotic kidney may present as a palpable abdominal mass in the newborn, and may suggest an ectopic ureter or ureterocele.

In older children, ureteral duplication may present as:

- Urinary tract infection - most commonly due to vesicoureteral reflux (flow of urine from the bladder into the ureter, rather than vice versa).

- Urinary incontinence in females occurs in cases of ectopic ureter entering the vagina, urethra or vestibule.

Nipple adenomas most commonly occur in 30- to 40-year-old women, but can also occur in men. They can also occur at any age, including in the elderly, in adolescence, and in infants.

Urethral strictures most commonly result from injury, urethral instrumentation, infection, non-infectious inflammatory conditions of the urethra, and after prior hypospadias surgery. Less common causes include congenital urethral strictures and those resulting from malignancy.

Urethral strictures after blunt trauma can generally be divided into two sub-types;

- Pelvic fracture-associated urethral disruption occurs in as many as 15% of severe pelvic fractures. These injuries are typically managed with suprapubic tube placement and delayed urethroplasty 3 months later. Early endoscopic realignment may be used in select cases instead of a suprapubic tube, but these patients should be monitored closely as vast majority of them will require urethroplasty.

- Blunt trauma to the perineum compresses the bulbar urethra against the pubic symphysis, causing a "crush" injury. These patients are typically treated with suprapubic tube and delayed urethroplasty.

Other specific causes of urethral stricture include:

- Instrumentation (e.g., after transurethral resection of prostate, transurethral resection of bladder tumor, or endoscopic kidney surgery)

- Infection (typically with Gonorrhea)

- Lichen sclerosus

- Surgery to address hypospadias can result in a delayed urethral stricture, even decades after the original surgery.