Osseous Metaplasia and Bone Marrow Elements in a Case of Renal Cell Carcinoma

Abstract

Renal cell carcinoma with osseous metaplasia and bone marrow elements is a relatively rare event in these tumors. We discuss pathological differential diagnosis for this tumor with a review of the literature on this unusual case.

Renal cell carcinoma with osseous metaplasia: A case report and literature review

“…Osseous metaplasia has also been reported in patients with renal diseases, including less than 20 cases of the major subtypes of RCC [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][23][24][25][26]. Table 1 summarizes clinicopathologic features of these cases, including the present case, reported in case studies of osseous metaplasia associated with RCC.…”

“…Sarcomatoid differentiation is also seen in a subset of RCCs and is generally associated with poor patient outcomes. By contrast, metaplastic bone formation with or without bone marrow elements in RCC is extremely rare yet has been reported predominantly in clear cell [2][3][4][5][6][7][8][9][10][11][12] and chromophobe [13][14][15][16] subtypes. We here present a case of papillary RCC with osseous metaplasia along with a review of the literature on this unusual condition.…”

Osseous Metaplasia in Mucinous Tubular and Spindle Cell Carcinoma of the Kidney: A Case of Massive, Bilateral Tumors

“…Surgical pathology was also able to identify heterotrophic bone formation. While calcified foci are well known and present in up to 10.3% of RCCs [ 3 ], ossification is extremely rare [ 10 , 11 ]. There is currently no clear mechanism of ossification identified; however, since RCCs are known to undergo hemorrhage, necrosis, fibrosis, and hyalinization, it is plausible that osseous metaplasia is secondary to these changes [ 12 ].…”

Renal Cell Carcinoma with Osseous Metaplasia

“…Calcification can be seen in both benign and malignant renal lesions. Differential diagnosis for calcified renal mass includes RCC, Wilms tumor, oncocytoma, metanephric adenoma [4], angiomyolipoma, intra renal aneurysms, cystic renal disease, renal abscess, echinococcal cysts, schistosomiasis, tuberculosis, xanthogranulomatous pyelonephritis, arteriovenous malformations and hematoma [5]. Osseous metaplasia opposed to calcification is a rare finding.…”