Young Teenage Male with Macroscopic Hematuria

Specimen Type:

Bladder

History:

A 15-year-old boy with macroscopic hematuria underwent a cystoscopy with bladder biopsy. Visualization by endoscopy shows a solitary exophytic papillary lesion (fig 4.1). At gross description, the lesion is received as multiple portions, in aggregate 2 cm x 1.5 cm x 0.3 cm. Representative cross-sections were submitted.

Pathologic Features:

Sections revealed a complex papillary proliferation of urothelium. The urothelium presents normal thickness in some focal areas but in general is greater than 7 layers (fig 4.2). Superficial (umbrella) cells are absent (fig 4.3). Nuclei are uniform in shape and spacing; the chromatin texture is finely granular, without significant nucleolar enlargement (fig 4.4). Mitotic figures are rare.

Papilloma: The WHO criteria for papilloma include five strict features:

  • lesion less than 2 cm in greatest dimension; (2) solitary (3) papillae consist of delicate fibrovascular cores lined by less than 7 layers of urothelium; (4) without mitotic figures or any significant cytologic atypia. Mild nuclear atypia is occasionally present; intact superficial (umbrella) cell layer; and (5) patients are less than 50 years of age.
  • Papilloma is uncommon, representing less than 3 % of papillary urothelial tumors. Urothelial papilloma does not have the capacity to invade or metastasize. However, it is neoplastic, with a small but significant potential for recurrence.

Polypoid cystitis: Although classically described as being associated with indwelling catheters, this lesion may arise as a reaction to any inflammatory insult to the urinary mucosa. This lesion appears as either an area of friable mucosa irregularity, thin finger-like papillae (Papillary cystitis), or edematous and broad-based papillae (Polypoid cystitis). Abundant chronic inflammation is present within the stoma accompanied by prominent and often ectatic blood vessels.

Papillary urothelial hyperplasia: Flat or papillary urothelial hyperplasia consists of a markedly thickened mucosa with few or no significant cytological abnormalities.

Differential Diagnosis:

Considering patient’s age, papilloma enters the major differential diagnosis (fig 4.5).

  • Polypoid cystitis
  • Papillary urothelial hyperplasia

Diagnosis:

Non-Invasive Grade 1 (OF 3) Papillary Urothelial Carcinoma (Who 1973 Classification).

Key Features:

  • Age: Usually > 50 years*
  • Size: Usually > 2 cm
  • Sex ratio (Male:female): 3:1
  • Microscopic findings:
    • Well-formed papillae: Present
    • Thickness of urothelium: Usually > 7 layers
    • Superficial umbrella cells: Usually present, may be absent
    • Cytology
      • Nuclear enlargement: slight to modetrate
      • Nuclear hyperchromasia: Slight
      • Chromatin: Slighty coarse or granular
      • Nucleolar enlargement: May be present
    • Mitotic figures: Rare
    • Stromal invasion: Uncommon

* In the case presented here, the patient is 15- year-old. Based on histological findings (urothelium greater than 7 layers (despite normal thickness present in some areas) and absence of superficial umbrella cells)), the diagnosis of urothelial carcinoma is retained.

  • Transitional cell carcinoma of the bladder occurs rarely during the first two decades of life. The malignancy is usually low grade and noninvasive, with a law recurrence rate
  • Transurethral resection and fulguration is the treatment of choice, and the prognosis is excellent
  Papilloma Grade I Carcinoma
Age (y) Younger (usually <50) Older (usually >50)
Sex (Male:female) 2:1 3:1
Size Small, usually <2cm Larger
Microscopic findings    
-Well-formed papillae Present Present
-Thicknes of Urothelium < 7 layers Usually > 7 layers
-Superficial umbrella cells Present Usually present
Cytology    
-Nuclear enlargement Rare or none Slight to moderate
-Nuclear hyperchromasia Rare or none Slight
-Chromatin Fine granular Slight coarse or granular
-Chromatin Absent May be present
Mitotic figures None Rare
Stromal Invasion Absent Uncommon

References:

  1. Hoenig DM, McRae S, Chen SC, et al. Transitional cell carcinoma of the bladder in the pediatric patient. J Urol. 1996; 156(1):203-5.
  2. Bostwick DG, Ramnani D, Cheng L. Diagnosis and grading of bladder cancer and associated lesions. Urol Clin North Am. 1999; 26(3):493-507.
  3. Cheng L, Darson M, Cheville JC, et al. Urothelial papilloma of the bladder. Clinical and biologic implications. Cancer. 1999; 86(10):2098-101.
  4. Cheng L, Neumann RM, Bostwick DG. Papillary urothelial neoplasms of low malignant potential. Clinical and biologic implications. Cancer. 1999; 86(10):2102-8.
  5. Mc Kenney JK, Amin MB, Young RH. Urothelial (Transitionnal Cell) Papilloma of the urinary bladder: A clinicopathologic study of 26 cases. Mod Pathol. 2003; 16(7):623-9.