Penile osteosarcoma

Abstract

Introduction Extraskeletal osteosarcoma arising in the penis is exceedingly rare and its major differential diagnosis is sarcomatoid carcinoma. Case presentation A 19-year-old patient noticed a deep nodule in the dorsal side of the penis 2 years before this presentation. No skin lesions were noted until recent ulceration. In both biopsy and penectomy specimen, atypical mononuclear cells were diffusely positive for SATB2 (a marker of osteoblastic differentiation), CD99 and vimentin. These cells were negative for pan-keratin, SOX10, S100, EMA, GATA3 and CD68 was expressed only in multinucleated giant (osteoclast-like) cells. Few areas suggestive of osteoid production were noted. Conclusion In high-grade sarcomas, including in the penis, SATB2 staining may be useful to identify extraskeletal osteosarcoma.

Penile Osteosarcoma: A Rare Extraosseous Site

“…The above patient presented primarily because of pain in his phallus, which had been present for about two months. Primary osteosarcoma of the penis, a form of EOS, is an extremely rare cancer with only nine case reports in literature so far [1][2][3][4][5][6][7][8][9], accounting for only 1% of soft tissue sarcomas. Its risk factors are not well established.…”

“…Its risk factors are not well established. This most commonly affects men aged 45-65 [7,11]; however, it has recently been reported in as young as a 19-year-old boy [9]. Some suspected risk factors for EOS include trauma, radiation, and dermatomyositis [12].…”

“…EOS are mostly high-grade with malignant osteoid and have cartilaginous elements [6,7]. Athanazio et al reported atypical mononuclear cells with diffusely positive special adenine-and thymine (AT)-rich sequence-binding protein 2 (SATB2), a marker of osteoblastic differentiation, cluster of differentiation 99 (CD99), and vimentin, and they concluded that SATB2 staining may be useful for identifying EOS [9]. In the reported case, the SATB2 nuclear staining is positive; however, unfortunately, alkaline phosphatase staining was not specifically performed on this specimen.…”

“…Rarely, it has also been described in the lung, prostate, scalp, mammary gland, spermatic cord, pelvis, and orbit. Among these sites, primary penile EOS ranks as the most uncommon, with only nine cases reported in the literature [1][2][3][4][5][6][7][8][9], and the youngest reported patient is a 19-year-old boy [9]. EOS expands an already rare differential for masses of the genitalia.…”

“…The main differential for its presentation is the dreaded penile cancer. However, EOS, if diagnosed in time, can be managed successfully by surgical resection, which may entail complete or partial penectomy [1][2][3][4][5][6][7][8][9]. The five-year survival of these patients varies between 25 and 37% [8], mostly because of the metastasis rate of this tumor.…”