Testicular Mass in an Adult

Specimen Type:

Testis

History:

44-year-old man presented with a very firm spermatic cord mass that was present for a number of years. The mass has increased in size from 2 cm to 5 cm over the past 2-3 years. The tumor was excised along with a hydrocele sac. Grossly, a firm calcified mass is identified in the spermatic cord measuring 5 x 3.5 x 3.5 cm, which is in direct continuity with the spermatic cord.  Cross sectioning of the lesion reveals a white densely calicified lesion with focal areas of whorled or marbled pattern. No necrosis and hemorrhage are present.

Pathologic Features:

The lesion predominantly consists of dense fibrous tissue with abundant hyalinized collagen with focal calcificatioan and ossifification (Figs 1, 2, 3, 4, 5). Patchy chronic inflammation and stromal myxoid changes are also present (Figs 6, 7). No cytologic atypia is appreciated (Fig 8).

Differential Diagnosis:

  • Fibroma of the tunics

Fibroma of the tunics:  This is very rare lesion and less than 10 documented cases reported in the literature. The tumor can be located entirely in the testis, pedunculated, or unattached to the tunica albuginea as a circumscribed paratesticular mass. Cellular fibromas should be distinguished from exceptionally rare fibrosarcoma of the testis using the similar criteria as in the ovary. These lesions are distinguished from leiomyoma (exceptionally rare in the testis) based on the hisotological features; actin staining is not reliable as a differential stain, since it is consistently expressed in fibroma.

Diagnosis:

Fibrous pseudotumor (fibromatous periorchitis, nodular periorchitis) with calcification and ossification.

Key Features:

  • Paucicellular lesion composed of abundant hyalinized collagen and scattered fibroblasts
  • Presence of chronic inflammatory infiltrates and granulation tissue
  • Secondary changes may be present, such as calcification or ossification

Comment: Fibrous pseudotumors of the testicular tunics and paratesticular soft tissue are uncommon lesions. They typically arise as painless scrotal masses that may be associated with a hydrocele or history of trauma or infection. Although these lesions are clinically worrisome for a malignant neoplasm, they are thought to be reactive in nature. These lesions are composed of dense fibrous tissue with interspersed bland fibroblasts, myofibroblasts and mixed inflammatory cells. Excision usually is curative. Typically, these masses are multinodular, but in rare cases they are diffuse, bandlike myofibroblastic proliferations that encase the testis and referred to as fibromatous periorchitis (reference 1).

Fibrous pseudotumor is distinguished from the rare fibroma of the tunics by its paucicellular nature and presence of inflammation in earlier stages.

References:

  1. Seethala RR, Tirkes AT, Weinstein S, Tomaszewski JE, Malkowicz SB, Genega EM. Diffuse fibrous pseudotumor of the testicular tunics associated with an inflamed hydrocele. Arch Pathol Lab Med. 2003 Jun;127(6):742-4.
  2. Jones MA, Young RH, Scully RE. Benign fibromatous tumors of the testis and paratesticular region: a report of 9 cases with a proposed classification of fibromatous tumors and tumor-like lesions. Am J Surg Pathol. 1997 Mar; 21(3):296-305.