Sarcomatoid chordoma: chordoma with a massive malignant spindle-cell component

We report a case of chordoma containing a spindle cell sarcomatoid component with a gradual transition from conventional chordoma. Immunohistochemically, many tumor cells in both conventional chordoma and sarcomatoid components were positive for cytokeratins (AE1/AE3, CAM5.2) and epithelial membrane antigen as well as vimentin. This report provides a rare example of sarcomatoid chordoma. Familiarity with this type of bone tumor should help to avoid confusion with dedifferentiated chordoma and other spindle cell sarcomas or carcinomas. Received: 25 February 2000 Revision requested: 28 March 2000 Revision received: 30 May 2000 Accepted: 28 June 2000     

Late presentation of solitary contralateral adrenal metastasis of renal cell carcinoma

We report a case of renal cell carcinoma with solitary metachronous contralateral adrenal metastasis occurring 23 years after radical nephrectomy. The patient was treated with adrenalectomy. He is alive with no evidence of disease 1 year postoperatively. Solitary metachronous contralateral adrenal metastases from renal cell carcinoma are rare clinical conditions that may occur very late. Metastasectomy is advocated and is probably beneficial for limited metastatic renal cell cancer. Received 18 June 1996; Revision received 20 September 1996; Accepted 11 October 1996     

Chondromyxoid fibroma of the acromium with soft tissue extension

Chondromyxoid fibroma is an unusual, benign tumor of cartilaginous origin and represents less than 1% of all primary bone tumors. It usually involves the long bones around the knee joint or the flat bones of the pelvis or ribs. Soft tissue extension is also thought to be rare in these lesions. They are usually eccentrically located in the metaphyses of the long bones and centrally in the flat bones. The radiographic appearances are characteristically those of a single, lytic lesion with lobulated margins, septations, cortical expansion and a sclerotic rim. Histologically, they display a lobulated pattern with spindle-shaped cells lying within a myxoid matrix with areas of hyaline cartilage. The differential diagnosis includes giant cell tumor, chondroblastoma or enchondroma as well as chondrosarcoma. The rarity of these lesions may render the diagnosis difficult to make, especially when the lesion involves an unusual site such as the acromium. Received: 21 June 1999 Revision requested: 27 September 1999 Revision received: 27 October 1999 Accepted: 28 October 1999     

Sclerotic osseous metastases from renal cell carcinoma

This case series describes and illustrates three cases of sclerotic osseous metastases from untreated renal cell carcinoma (RCC). RCC is commonly metastatic to the skeleton but almost always produces lytic metastases, with only three prior reports of sclerotic metastases identified in the literature. Sclerotic metastasis causing low back pain was the initial disease presentation in two of the three patients in this case series and the first manifestation of metastatic disease in one. The most common metastatic sites of RCC, i.e., retroperitoneal lymph nodes, lung, and liver, were not identified in any of the cases, and skeletal involvement with epidural extension was the only site of metastasis in two. Pathologic specimens from all three cases revealed RCC of high nuclear grade.     

Foreign-body granuloma of the kidney: CT, MR and pathologic correlation

The differential diagnosis of renal masses containing fatty foci is limited to a small number of well-defined tumors, angiomyolipoma being the most frequent. In recent years clear cell carcinomas with intratumoral fatty foci have been reported, due to either entrapment of local fat or to regressive adipose metaplasia. Demonstration of focal calcifications is a valuable sign, being relatively common in carcinomas while rare in more benign lesions. We report a case of a foreign-body granuloma of the kidney, containing both calcifications and foci of fat. The value of this case, in our opinion, is that it demonstrates that detection of the previously mentioned features in a renal mass does not necessarily imply a presumptive diagnosis of renal cell carcinoma. Received: 11 June 1998; Revision received: 3 November 1998; Accepted: 23 November 1998     

Xanthogranulomatous pyelonephritis: MRI findings in the diffuse and the focal type

Two cases of xanthogranulomatous pyelonephritis (XGP) are presented with emphasis on MR appearances. One case is the diffuse type of XGP secondary to chronic obstruction caused by transitional cell carcinoma of the renal pelvis. The other case is the focal or “tumefactive” type of XGP which mimics renal cell carcinoma. Received: 15 February 1999; Revised: 14 June 1999; Accepted: 8 July 1999     

肉瘤样肾细胞癌临床病理分析

目的探讨肾细胞癌肉瘤样改变的病理特征及其临床意义。方法复习本院手术切除的肉瘤样肾细胞癌病例切片，观察肉瘤样成分的形态、数量及其对肿瘤分期和预后的影响。结果16例伴有肉瘤样改变的肾细胞癌中，9例为透明细胞癌，3例为乳头状肾细胞癌，2例为嫌色细胞癌，2例为集合管癌。肉瘤样成分大于50％者9例，少于50％者7例，大于50％病例中T2 1例，T3和T4共8例；而肉瘤样成分少于50％的病例中T2 4例，T3和T4共3例。肉瘤样区域类似纤维肉瘤或恶性纤维组织细胞瘤。患者平均存活期为19个月（8-154个月）。肉瘤样成分超过50％的病例平均存活期为14个月，而少于50％的病例存活期为27个月，两者有明显差别（P〈0．01）。结论肾细胞癌肉瘤样改变中透明细胞癌发生率最高，而且与肿瘤分期和预后密切相关，肉瘤样成分越多，预后越差。     

Sarcomatoid renal cell carcinoma: rapid dissemination detected on FDG PET-CT

We present the FDG PET-CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para-aortic nodes, a PET-CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET-CT findings in sarcomatoid renal cell carcinomas.     

Spontaneous regression of pulmonary and adrenal metastases following percutaneous radiofrequency ablation of a recurrent renal cell carcinoma

The spontaneous regression of metastatic lesions from renal cell carcinoma (RCC) is extremely rare, but may be encountered following cytoreductive treatments. We report a case of a recurrent RCC with multiple metastatic lesions which spontaneously regressed after undergoing radiofrequency ablation of the renal tumor.     

Malignant vascular lesions of bone: radiologic and pathologic features

The malignant vascular tumors of bone represent an uncommon diverse group of tumors with widely variable clinical and radiographic presentations. Although the radiographic imaging features of the lytic osseous lesions typically seen with this group of tumors are relatively nonspecific, the propensity to develop multifocal disease in an anatomic region is a feature that can be helpful in suggesting the diagnosis of a vascular tumor. The differential diagnosis varies according to the age of the patient and presence of solitary or multifocal disease. The histologic features are variable and range from tumors with vasoformative features to those that mimic mesenchymal neoplasm or metastatic carcinoma. Familiarity with the radiographic and pathologic spectrum of disease is essential for making an accurate diagnosis in this diverse group of neoplasms. This paper will provide a review of the nomenclature for the malignant vascular tumors of bone and discuss the radiographic and pathologic differential diagnosis. Received: 17 December 1999 Revision requested: 8 February 2000 Revision received: 19 May 2000 Accepted: 9 June 2000     

Sarcomatoid nephrocarcinoma. Correlation of radiological, histopathological and prognostic features

Fifteen patients with sarcomatoid renal cell carcinoma were studied from 1975 through 1987. For each case the radiological, sonographic (US), and histopathological features were reviewed. Neither ivp nor US detected any specific patterns, though demonstrating frequently-necrotic and infiltrating masses. Angiography and/or CT were more useful because they allowed the staging of the tumors and the evaluation of their vascularity. In particular, a frequent correlation was observed between the degree of vascularity and the percentage of sarcomatoid component at histopathology. Sarcomatoid renal cell carcinoma were hypo-avascular in 7 cases and hypervascular in 8. Six of the 7 hypo-avascular cases had a high percentage of sarcomatoid tissue (greater than 50%) and were highly malignant. Seven of the 8 hypervascular neoplasms had a low percentage of sarcomatoid component and presented radiological features similar to clear/granular cell tumors. The survival of the patients with sarcomatoid tumors was much shorter than that of the patients with other kidney carcinomas. Among sarcomatoid tumors, prognosis was worst for the patients with hypo-avascular neoplasms.     

Nasopharyngeal carcinoma: pattern of skeletal metastases

The records of 153 nasopharyngeal carcinoma patients with skeletal metastases were reviewed. The skeletal system was the most common site of distant metastases. The patients who developed skeletal metastases were significantly younger than those without skeletal metastases, although there was no difference between sexes. The pattern of skeletal involvement conforms to the general pattern, the spine and pelvis being the common sites. The first region of involvement was lumbar spine (28.4%), then dorsal spine (27.7%), sacrum and pelvis (16.3%), femur (9.9%), rib and sternum (7.8%), humerus (5.0%), cervical spine (3.5%) and skull vault (1.4%). Radiologically, the lesions were lytic in 66.0%, mixed lytic and sclerotic in 12.8% and sclerotic in 21.2%. The time to development of symptomatic skeletal metastases of mixed or sclerotic nature was significantly longer than lytic lesions, and patients with mixed or sclerotic metastases also had better survival.     

Cystic fibrous dysplasia mimicking giant cell tumor: MRI appearance

We report the case of a 43-year-old man who presented with an osteolytic and expansive lesion in the left distal femur mimicking a giant cell tumor. Magnetic resonance imaging (MRI) showed that most of the lesion was cystic, and histological examination revealed fibrous dysplasia with marked cystic degeneration. Radiographic findings of cystic fibrous dysplasia in the end of a long bone may be similar to those of a giant cell tumor, and a biopsy is essential for the final diagnosis. Received: 4 June 1999 Revision requested: 10 August 1999 Revision received: 13 September 1999 Accepted: 15 September 1999     

Hyperfunctioning parathyroid carcinoma

Primary hyperparathyroidism is rarely caused by carcinoma. We report a patient who manifested many of the clinical and radiographic features of the disease. When encountering symptomatic hypercalcemia with or without a palpable neck mass, carcinoma should be considered in the differential diagnosis. Patient survival depends on an aggressive surgical approach to the primary lesion and recurrent disease. Received: 27 May 1999 Revision requested: 28 June 1999 Revision received: 22 September 1999 Accepted: 27 September 1999     

Intramuscular spindle cell hemangioendothelioma

Spindle cell hemangioendothelioma occurring in skeletal muscle is extremely rare. No reported studies have performed an imaging evaluation of intramuscular spindle cell hemangioendothelioma. We report on such a tumor arising in an unusual site, the right extensor digiti minimi, in a 46-year-old woman. An en bloc resection was performed and the patient has been disease free for 8 years. Radiologic imaging in the present case showed similar findings to those described in intramuscular hemangioma. Received: 11 January 1999 Revision requested: 18 March 1999 Revision received: 22 April 1999 Accepted: 23 April 1999     

Chronic ulceration of the leg following extensive scarring due to a snake bite complicated by squamous cell carcinoma

Chronic ulcers of the leg are common in Brazil, perhaps more common than in the developed world. We report a case of a chronic ulcer of the leg following extensive scarring due to a bite by a venomous snake, which eventually led to a squamous cell carcinoma. Received: 16 August 1999 Revision requested: 8 October 1999 Revision received: 10 December 1999 Accepted: 15 December 1999     

Metastatic RCC arising in a transplant kidney

We report a case of metastatic renal cell carcinoma arising in a cadaver transplant kidney 6 years after transplantation. Due to molecular analysis of the tumor tissue we could prove that the carcinoma originated from the male donor. After tumor resection and interruption of immunotherapy, the concomitant bone and lymph node metastases resolved with alpha-interferon and interleukin-2-based immunotherapy. Received 28 August 1997; Revision received 23 December 1997; Accepted 29 December 1997     

Widespread metastases from sarcomatoid renal cell carcinoma detected by 18F-FDG positron emission tomography/computed tomography

We present a case of sarcomatoid renal cell carcinoma (RCC). Although preoperative computed tomography (CT) scans demonstrated small lung and pleural nodules and mediastinal lymphadenopathy, these findings were not conclusive for metastases. Whole-body fluorine-18 fluorodeoxyglucose positron emission tomography and CT (FDG-PET/CT) performed 15 days after right nephrectomy showed intense FDG uptake in the aforementioned lesions (lung and pleural nodules, mediastinal lymph nodes). Unexpectedly, focal increased FDG uptake was found in the right infraspinatus muscle. FDG-PET/CT was considered useful for evaluating distant metastases and thus portending the aggressive nature of sarcomatoid RCC.     

Solitary infantile myofibromatosis involving the clavicle

A rare case of solitary infantile myofibromatosis of bone is reported in the right clavicle of a 15-year-old boy. A radiograph demonstrated an osteolytic lesion with a sharp margin and a sclerotic rim. CT revealed a circumscribed lesion with slight expansion of the cortex. On MRI the lesion appeared isointense to muscle on T1-weighted images, bright on T2-weighted images, and showed marked gadolinium enhancement. The patient was well, without evidence of recurrence or metastasis, 4 years and 5 months following resection. Received: 11 August 1998 Revision requested: 5 October 1998, 18 March 1999 Revision received: 15 March 1999, 23 April 1999 Accepted: 28 April 1999