| Epidemiology | MTSCC occurs in patients with a wide age range. Affected patients range from 13 to 82 years old with a mean age of 53 and a male to female ratio of 1:4 (Srigley, 2004; Eble, 2003; Srigley and Delahunt, 2009). |
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| Figure 1. Mucinous tubular and spindle cell carcinoma of the kidney. The well circumscribed tumor is composed of areas tubular and spindle cells (A, B). Compact elongated tubules lined by low cuboidal cells and tumor-associated mucin are present (C, D). There are parallel tubular arrays and cords of cuboidal and spindle cells (E, F). |
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| Pathology | Macroscopically, MTSCCs are well circumscribed tumors located centrally or cortically. Tumors range from less than 1 cm to greater than 18 cm in diameter and most tumors measure 2 to 4 cm. Cross sections of the tumor display uniform light tan, yellow or gray tissues with minimal hemorrhage and/or necrosis.
Microscopically, the neoplasms consists of small elongated tubules embedded in a background of basophilic mucinous stroma. There are areas of neoplastic cells arranged in curvilinear architecture separated by mucin. Closely parallel and collapsed tubular arrays with a spindle-cell appearance are noted (Figure 1). Tumors with focal neuroendocrine differentiation or sarcomatoid change have been reported (Kuroda et al., 2004; Dhillon et al., 2009).
Figure 2 shows positive cytoplasmic staining of CD10, CK7, and AMACR in neoplastic cells arranged in compact solid tubules and parallel cords. |
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| Figure 2. Immunoprofile of mucinous tubular and spindle cell carcinoma of the kidney. The neoplastic cells in solid tubules and parallel cords are stained positive for CD10 (G), CK7 (H), and AMACR (I). |
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| Prognosis | In general, MTSCC possesses favorable prognosis. This tumor is considered as a low-grade carcinoma although one case with tumor metastasis has been reported (Dhillon et al., 2009). |
| Note | MTSCC exhibits +7 and +20 in our current case (Figure 3). It has been shown that multiple chromosomal alterations including losses of chromosome 1, 4, 6, 8, 9, 13, 14, 15, 18, and 22 are involved (Rakozy et al., 2002). In addition, gains of chromosomes 12q, 16q, 17, and 20q identified by CGH analyses have been reported (Billis, 2002). Apparent gains of chromosome 7, 11, 16, and 17 have been observed (Rakozy et al., 2002; Billis, 2002). |
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| Figure 3. Karyotype of mucinous tubular and spindle cell carcinoma. |
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| Phenotypic, molecular and ultrastructural studies of a novel low grade renal epithelial neoplasm possibly related to the loop of Henle. |
| Billis A. |
| Int Braz J Urol. 2002 Sep-Oct;28(5):477-8. |
| PMID 15748380 |
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| Low-grade tubular-mucinous renal neoplasms: morphologic, immunohistochemical, and genetic features. |
| Rakozy C, Schmahl GE, Bogner S, Storkel S. |
| Mod Pathol. 2002 Nov;15(11):1162-71. |
| PMID 12429795 |
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| Mucinous tubular and spindle cell carcinoma and post-neuroblastoma carcinoma: newly recognised entities in the renal cell carcinoma family. |
| Eble JN. |
| Pathology. 2003 Dec;35(6):499-504. (REVIEW) |
| PMID 14660100 |
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| Low-grade tubular-mucinous renal neoplasm with neuroendocrine differentiation: a histological, immunohistochemical and ultrastructural study. |
| Kuroda N, Nakamura S, Miyazaki E, Hayashi Y, Taguchi T, Hiroi M, Yamasaki Y, Shuin T, Enzan H. |
| Pathol Int. 2004 Mar;54(3):201-7. |
| PMID 14989744 |
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| Mucinous tubular and spindle cell carcinoma. |
| Srigley J. |
| World Health Organization Classification of Tumours. Pathology and Genetics of Tumours of the Urinary System and Male Genital Organs. In: Eble JN, Sauter G, Epstein JI, et al. (eds). IARC Press: Lyon, 2004. |
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| Mucinous tubular and spindle cell carcinoma of the kidney with sarcomatoid change. |
| Dhillon J, Amin MB, Selbs E, Turi GK, Paner GP, Reuter VE. |
| Am J Surg Pathol. 2009 Jan;33(1):44-9. |
| PMID 18941398 |
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| Uncommon and recently described renal carcinomas. |
| Srigley JR, Delahunt B. |
| Mod Pathol. 2009 Jun;22 Suppl 2:S2-S23. (REVIEW) |
| PMID 19494850 |
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