Primary Osteosarcoma of the Breast: Report of 2 Cases

Two distinct histologic variants of primary breast osteosarcoma in 2 elderly women are described. The first patient was an 88-year-old woman with a long-standing, slow-growing, 18-cm mass in her right breast. The second patient was a 96-year-old woman with a recently self-detected, painless, 7.5-cm lump in her left breast. Clinically, there was no evidence of metastasis, and both women underwent simple mastectomy. Histologic features of both specimens were those of high-grade primary breast osteosarcoma. The first patient's tumor was classified as a chondroblastic variant, and the second as an osteoblastic variant of osteosarcoma. The patients were alive without evidence of local recurrence or hematogenous spread at a 16- and 4-month follow-up, respectively. Primary mammary osteosarcoma should be distinguished from metaplastic/ sarcomatoid carcinoma with heterologous osseous/cartilaginous differentiation or malignant phyllodes tumor because it has a different biological behavior and requires a different treatment approach.

Concurrent angiomyolipoma and two oncocytomas in the same kidney

We report on a rare case of synchronous angiomyolipoma (AML) and 2 oncocytomas (OCs) in the same kidney of a 73-year-old woman. During the course of a follow-up for a long-standing staghorn calculus in the left kidney, a 4-cm right suprarenal mass and a small solid nodule adjacent to a cyst in the midportion of the right kidney were radiographically discovered. A radical nephrectomy was performed. The suprarenal tumor was found to be an AML, and the small nodule was an OC (1.5 cm). An additional OC (0.8 cm) elsewhere in the right kidney was also identified. The coexistence of AML and other renal tumors is uncommon. Among reported cases, conventional renal cell carcinoma, possibly reflecting its higher incidence, has been the most common concurrent tumor with AML. Although only rare cases of simultaneous AML and OC have been reported in the literature, it appears that the proportion of OC among concurrent renal tumors with AML is higher than expected based on its frequency among all surgically resected renal neoplasms. Whether there is a pathogenetic association between AML and OC needs to be further investigated.

Mucinous tubular and spindle cell carcinoma of kidney is probably a variant of papillary renal cell carcinoma with spindle cell features

Mucinous tubular and spindle cell carcinoma is a rare and newly described type of renal cell carcinoma (RCC) with a relatively indolent behavior. However, its histogenetic origin or line of differentiation remains unclear. Twelve cases of mucinous tubular and spindle cell carcinoma were identified and retrieved from the files of 3 institutions. Detailed morphological features, as well as their immunohistochemical profile established with markers of proximal renal tubules (RCC marker antigen, CD15, and alpha-methylacyl-CoA racemase) and of distal renal tubules (kidney-specific cadherin and cytokeratin 7), were studied. The age range of the patients was 35 to 73 years with a median of 56 years. The male to female ratio was 1:3. All of the patients were alive with follow-up between 4 and 38 months. All the tumors were confined to the kidney with a mean tumor size of 6.9 cm (range, 1.8-17 cm). The tumors were composed of variable proportions of tubular and spindle cell areas with focal to prominent mucinous or myxoid stroma. Foamy macrophages were seen in 10 cases and were prominent in 4 cases. A focal compressed tubulopapillary growth pattern was seen in 10 cases. The tumor cells were uniformly cuboidal with ovoid to round nuclei and inconspicuous nucleoli (Furhman nuclear grade 3 in 6 cases). Focal necrosis was seen in 3 cases. Immunostains showed that tumors were positive for RCC marker antigen (11/12), alpha-methylacyl-CoA racemase (11/12), CD15 (8/12), CD10 (2/12), kidney-specific cadherin (1/12), and cytokeratin 7 (11/12). Its morphological features as well as a strong preferential expression of proximal tubule markers suggest that this tumor is a type of RCC with proximal tubular differentiation, which appears closely related to or represents a morphological variant of papillary RCC.

Juxtaglomerular cell tumor of kidney with CD34 and CD117 immunoreactivity: report of 5 cases

CONTEXT

Juxtaglomerular cell tumor is a rare renal neoplasm. Renin immunohistochemistry and electron microscopic documentation of rhomboid crystals are the primary methods of diagnosing this benign tumor.

OBJECTIVES

In this retrospective study, we evaluated the morphologic, immunohistochemical, and ultrastructural features of 5 cases of juxtaglomerular cell tumor to determine the effectiveness of CD34 and CD117 immunohistochemistry for the diagnosis of this tumor.

DESIGN

We reviewed 5 cases with clinical, histologic, immunohistochemical, and ultrastructural aspects.

RESULTS

Three women and 2 men with a mean age of 37.8 years (range, 16-60 years) were included in this study. All patients presented with severe hypertension. All tumors were well circumscribed and ranged from 1.5 cm to 8.5 cm (mean, 4.4 cm). On light microscopic examination, we found solid sheets and nests of tumor cells with oval-to-round nuclei and eosinophilic cytoplasm. Low-power microscopic examination disclosed a hemangiopericytic vascular pattern. Immunohistochemistry results were as follows: vimentin (positive), renin (weakly positive), smooth muscle actin (focal immunoreactivity), and cytokeratin (negative). All 5 tumors were immunoreactive for CD34 and CD117. Electron microscopy revealed rhomboid crystals in the cytoplasm. Postoperatively, 4 patients were normotensive and 1 patient experienced persistent mild hypertension.

CONCLUSIONS

Our findings indicate that immunohistochemistry for CD34 and CD117 are effective at diagnosing juxtaglomerular cell tumor. Juxtaglomerular cell tumor should be considered in the diagnosis of any renal tumors with epithelioid cells and negative initial cytokeratin immunohistochemistry.

Thyroid follicular carcinoma-like tumor of kidney: a case report with morphologic, immunohistochemical, and genetic analysis

We present an unusual renal tumor, which has not been classified under a known subtype of renal cell carcinoma (RCC) and characteristically shows similar histology to thyroid follicular carcinoma. The patient was a 32-year-old asymptomatic woman who was found to have a kidney mass during her annual physical examination. She had no lesions in the thyroid during physical and ultrasound examinations, and there was no abnormal thyroid function test. Neither mediastinal nor ovarian abnormalities were observed. The resected kidney showed a well-defined nodular tumor measuring 11.8x8.0x8.0 cm. The mass was protruding into the pelvic cavity with areas of yellowish geographic necrosis. Histologically, the tumor showed follicular architectures with inspissated colloid-like material in their lumina. No conventional (clear cell) RCC or any other known subtypes of RCC component was observed. Immunohistochemically, the tumor cells showed intensive staining for cytokeratin (CK) cocktail AE1/AE3 and CD10 and were not reactive to thyroid transcription factor-1 and thyroglobulin. The staining of CK35betaH11 and vimentin revealed focal cytoplasmic reaction. The tumor cells were completely negative for CK7, CK19, CK20, CK34betaE12, carcinoembryonic antigen, epithelial membrane antigen, and CD15. Chromosomal gains of 7q36, 8q24, 12, 16, 17p11-q11, 17q24, 19q, 20q13, 21q22.3, and Xp and losses of 1p36, 3, and 9q21-33 were detected by comparative genomic hybridization. These findings are dissimilar to previously classified renal neoplasm. Only a report that included three cases of primary thyroid-like renal tumor has been described in the abstract form. However, there is no fully documented case on this unusual form of RCC, which morphologically resembles that of thyroid follicular carcinoma. Herein, we present a new case of thyroid follicular carcinoma-like tumor of the kidney with a chromosomal study and review of the literature.

Characterization of the myxoid variant of hibernoma

Hibernomas are rare benign neoplasms composed of brown adipose tissue. Although they were first mentioned in the literature almost a century ago, relatively few reports have documented their range of pathological features. Multivacuolated fat cells with small, central nuclei are typical features of hibernomas. Based on the nature of the stroma and the appearance of the multivacuolated cells, 4 categories of hibernomas are described: typical, lipoma-like, myxoid, and spindle cell. The myxoid variant is very rare. In this report, we present and characterize the spectrum of morphological features of the myxoid variant of hibernoma by describing the case of a 45-year-old white man who was referred to our hospital for treatment of an ovoid mass in the posterior segment of the right deltoid region. Histopathologic examination of the resected specimen revealed a multilobulated, tan-yellow, variegated tumor with a rubbery consistency that was separated by thick fibrous septa with interspersed collections of foamy histiocytes. The mass was initially diagnosed as schwannoma with degenerative changes, but workup revealed a myxoid variant of hibernoma. This report highlights recent advances that may help confirm the diagnosis and explain the differential diagnosis of this rare tumor. This is one of only a few cases of a myxoid variant of hibernoma reported in the literature.

Mucinous tubular and spindle cell carcinoma of the kidney with neuroendocrine differentiation: report of two cases

We encountered 2 cases of mucinous tubular and spindle cell carcinoma (MTSCC) during a short time. In a 61-year-old man who had macroscopic hematuria for 1 month, the 14.5 x 14.0 x 12.0-cm resected tumor involved the right middle aspect of the renal parenchyma and compressed the renal pelvis. In an asymptomatic 47-year-old man, a renal tumor was found during an annual physical examination. The 3.5 x 3.0 x 2.0-cm tumor was located at the upper pole of the right kidney. The histologic findings in both cases were similar Tumors consisted of tightly packed, small, elongated tubules separated by pale mucinous stroma. The tumor cells were cuboidal to spindled with eosinophilic cytoplasm and low nuclear grade. Mitoses were few or nonexistent and without abnormal figures. Both tumors were immunoreactive for cytokeratin (CK) cocktail (AE1/AE3), high-molecular-weight CK (34betaE12), low-molecular-weight CK (35betaH11), CK7, epithelial membrane antigen, E-cadherin, and vimentin. The tumor cells also were reactive for neuron-specific enolase, chromogranin, and synaptophysin. The ultrastructure of the tumor cells contained abundant mitochondria, junctional complex, and dense-core neurosecretory granules. We present 2 additional cases of MTSCC showing typical morphologic features with neuroendocrine differentiation.

Fine needle aspiration cytology of a low grade myxoid renal epithelial neoplasm: a case report

BACKGROUND

Recently, several case reports have described a rare but distinct subtype of renal tumor, referred to as a "low grade renal epithelial neoplasm," that appears to have a better prognosis than conventional renal cell carcinoma does. This report describes the cytologic features of this tumor as determined by fine needle aspiration (FNA) biopsy.

CASE

A 53-year-old woman with a history of lymphoma had a renal mass incidentally discovered on an abdominal computed tomographic scan performed for lymphoma restaging. Results of an FNA biopsy showed relatively uniform, medium-sized tumor cells with moderate amounts of finely vacuolated or wispy cytoplasm and indistinct cell borders. The nuclei were primarily round with coarse chromatin and had prominent nucleoli. In the cell block preparation, the tumor cells showed a tubular architecture and an abundant myxoid matrix. The patient underwent a partial nephrectomy. The tumor was classified as a low grade myxoid renal epithelial tumor.

CONCLUSION

This unusual kidney tumor appears to have distinctive cytomorphologic features, including a uniform population of epithelial cells with round nuclei, an abundant myxoid matrix and tubular architecture.

Adenomatoid tumor of the adrenal gland: a clinicopathologic study of 3 cases

Adenomatoid tumors are relatively uncommon benign neoplasms of mesothelial origin, usually occurring in the male and female genital tracts. Rare extragenital adenomatoid tumors have been identified in the adrenal glands, heart, mesentery, pleura, and lymph nodes. In the adrenal gland, adenomatoid tumors may pose a diagnostic challenge. The differential diagnosis includes adrenocortical carcinoma and metastatic carcinoma, especially signet ring cell carcinoma. Because of its glandular pattern, an adenomatoid tumor may be confused with an adenocarcinoma. We present 3 cases of adrenal adenomatoid tumors, including one with a concurrent large hemorrhagic vascular adrenal cyst. The adenomatoid tumors were unilateral, appeared solid and white, and varied from 1.7 to 4.2 cm in diameter. They occurred in 3 male patients aged 33, 33, and 46 years. One patient presented with abdominal pain due to the presence of a concurrent large adrenal cyst. The tumor was an incidental radiological finding in another case and was discovered during the course of a workup for hypertension in the third case. The light microscopic appearances were consistent with those of typical adenomatoid tumors. Immunohistochemical stains for calretinin and cytokeratin 5/6 were positive, confirming the tumors' mesothelial origin. Ultrastructural studies performed in 2 cases revealed microvilli and desmosomes. Follow-up showed no evidence of recurrence or metastasis. In our experience, the key to the diagnosis of this rare benign tumor is to consider adenomatoid tumor in the differential diagnosis of any glandular tumor occurring in the adrenal gland.

Small cell carcinoma of the bladder: a contemporary clinicopathological study of 51 cases

AIMS

We present 51 cases of primary small cell carcinoma of the bladder in a clinicopathological study with emphasis on features that aid in the initial recognition and diagnosis of small cell carcinoma of the bladder.

METHODS AND RESULTS

The patients were 40 men and 11 women between the ages of 39 and 87 years (mean age 67 years). Clinical data were available in 41 cases. The most common symptomatology was haematuria in 63% of the patients while dysuria was present in 12%. Thirty-eight patients were caucasians; seven patients were Hispanics; two patients were Asian; one patient was African-American; in the three additional patients no racial information was obtained. Biopsy material was obtained in all of the patients. Cystectomy was performed in 20 patients. At diagnosis, clinical stage was as follows: stage I in two (5%), stage II in 18 (44%), stage III in 10 (24%), and stage IV in 11 (27%). Histologically, urothelial carcinoma was present in 70% of the cases, adenocarcinoma in 8%, and squamous cell carcinoma in 10% of the cases. Small cell carcinoma was the only histology present in only 12% of the cases studied. Immunohistochemical studies using chromogranin, synaptophysin and chromogranin were positive in 30-70% of the cases.

CONCLUSIONS

The present study highlights the unusual phenomenon of pure small cell carcinoma of the bladder and its association with other non-small cell carcinomas in that anatomical location. In addition, the study highlights the different modalities employed to treat patients in whom there is a component of small cell carcinoma of the bladder.

Ewing sarcoma/peripheral primitive neuroectodermal tumor: adult abdominal tumors with an Ewing sarcoma gene rearrangement demonstrated by fluorescence in situ hybridization in paraffin sections

The differential diagnosis of small round cell tumors is exhaustive and requires ancillary studies. Relatively recently, fluorescence in situ hybridization (FISH) using probes for specific gene rearrangements has gained wide acceptance. This technique is particularly useful in the differential diagnosis of Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) and desmoplastic small round-cell tumor (DSRCT). In ES/PNET, the EWS gene is juxtaposed to the FLI-1 gene in 85% of cases and to the ERG gene in another 7% of cases; the EWS gene is juxtaposed to the WTI gene in DSRCT. Documentation of the EWS gene rearrangements in EWS/PNET has previously been demonstrated in frozen tissue. We report 2 unusual cases of EWS/PNET diagnosed in abdominal tumors in adults. Although the immunohistochemical results supported a diagnosis of ES/PNET, 1 case morphologically resembled DSRCT. The diagnosis in these 2 cases was confirmed by the FISH demonstration of EWS/FLI-1 gene fusion in paraffin-embedded tissue. Thus, the usefulness of FISH demonstration of an EWS gene rearrangement with these specific probes in such unusual cases is supported and is demonstrated in paraffin-embedded tissue.

Lymphoepithelioma-like carcinoma of the breast: Report of a case mimicking lymphoma

Only 10 cases of lymphoepithelioma-like carcinoma of the breast have been reported in the literature. This report adds one more case to the published literature. A 62-year-old woman presented with a mass in her left breast on physical examination. The mammographic images showed a 3.0 cm, poorly defined mass in the upper outer quadrant. A biopsy was recommended. The gross specimen consisted of a 5 cm portion of breast parenchyma with no discrete tumor. On microscopic examination, the tumor was composed of sheets of epithelioid cells arranged as single cells or in cords partially obscured by a dense lymphocytic infiltrate. The epitheliod cells extensively expressed cytokeratin stain, but did not express E-cadherin. The lymphoid cells expressed L26 stain in the germinal centers, and CD3 stain in the T lymphocytes surrounding the germinal centers and in between tumor cells. In situ hybridization showed no evidence of Epstein-Barr virus infection in the tumor cells. An overall review of 11 cases shows that the disease is usually seen in older patients. In situ and invasive lobular component was reported in 36% of the cases. Eight of 11 were negative for E-cadherin, 36% were estrogen receptor-positive, 18% were progesterone receptor-positive, and all of them were HER2/neu negative. None of the reported cases have been associated with Epstein-Barr virus infection. Only two of the cases showed lymph node metastasis, and long-term follow-up in one of them showed good prognosis. In summary, lymphoepithelioma-like carcinoma of the breast is a tumor with a good prognosis that should be considered as a possible diagnosis in breast tumors with an intense lymphocytic infiltrate.

Triple synchronous neoplasms in one kidney: report of a case and review of the literature

We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature.

Risk-adapted treatment for patients with clinical stage I nonseminomatous germ cell tumor of the testis

OBJECTIVES

To evaluate whether two courses of chemotherapy after orchiectomy in patients with clinical Stage I nonseminomatous germ cell testicular tumor at high risk of relapse will spare patients additional chemotherapy or surgery.

METHODS

High-risk patients had one or more of the following: preorchiectomy alpha-fetoprotein level of 80 ng/dL or greater, 80% embryonal cell carcinoma or greater, or vessel invasion in the primary tumor. Low-risk patients had none of these factors or had 50% teratoma or more without vessel invasion. High-risk patients were offered two 21-day courses of outpatient chemotherapy consisting of carboplatin, etoposide, and bleomycin. Low-risk patients and high-risk patients not receiving chemotherapy were observed.

RESULTS

Of 99 patients, we classified 76 as high risk and 23 as low risk of relapse. All but eight of the high-risk patients received chemotherapy. No patient who underwent chemotherapy developed relapse, although 1 patient with normal biomarkers and a late-appearing mass underwent retroperitoneal lymphadenectomy for mature teratoma. Two of the 23 low-risk patients had disease relapse; both successfully underwent chemotherapy. The nonhematologic toxicity was mild in patients receiving chemotherapy, and no patient required hospitalization. The median follow-up was 38 months (range 9 to 69).

CONCLUSIONS

Two courses of postorchiectomy adjuvant chemotherapy were safe and well tolerated and markedly decreased the relapse rate in high-risk patients with clinical Stage I nonseminomatous germ cell testicular tumor without additional surgery or more protracted chemotherapy. This approach may avoid potential problems with compliance and diminish the cost of scrupulous follow-up. Our results support that surveillance for carefully selected patients at a low risk of relapse is appropriate.

Synovial Sarcoma of the Kidney With Rhabdoid Features

We report 3 cases of synovial sarcoma with rhabdoid features, initially diagnosed as adult rhabdoid tumors. Two women (case nos. 1 and 2, 35 years and 27 years of age, respectively) and one man (case no. 3, 26 years of age) presented to their physicians with right flank pain. On physical examination, a poorly defined, firm, palpable mass was found in the upper right quadrant of the abdomen in all cases. Sonography and computed tomography revealed solid, cystic masses in the right kidneys that ranged in size from 8.5 to 20.0 cm. Right radical nephrectomies were performed in all patients. One patient died of disease, and the other two patients were alive and disease-free after chemotherapy and radiotherapy. Microscopic examination revealed that the tumors were composed mostly of rhabdoid cells with eccentrically located nuclei, prominent nucleoli, and eosinophilic cytoplasm. We also found areas of fasciculated spindle cells, sharply separated from or irregularly admixed with areas of rhabdoid cells. There was tumor necrosis, but no epithelial areas were seen. Hemangiopericytic vasculature was at least focally observed in all cases. The tumor cells were positive for CD99 and bcl-2 in all cases and for CD56 in two cases and negative for CD34 and smooth muscle actin in all cases. The cells in case no. 1 were focally positive for cytokeratin. To verify the possibility of synovial sarcoma with rhabdoid features, reverse transcriptase polymerase chain reaction using RNA extracted from frozen tissue in case no. 1 and formalin-fixed, paraffin-embedded tissue in case nos. 2 and 3 was performed. SYT-SSX2 transcripts were detected in all 3 cases. These cases indicate that synovial sarcoma of the kidney should be considered in the differential diagnosis of mesenchymal kidney tumors with prominent rhabdoid features. A subset of adult rhabdoid tumors may be a rhabdoid variant of synovial sarcoma, and molecular studies to detect SYT-SSX fusion transcripts are recommended for an accurate diagnosis.

Breast carcinoma with choriocarcinomatous features

Although breast carcinomas have been shown to produce various ectopic substances, including human chorionic gonadotropin, it is rare to identify morphologic differentiation compatible with the hormone produced by a tumor. Presently, only eight cases of breast carcinoma with focal choriocarcinomatous differentiation have been reported in the literature. This article describes the pathologic findings, immunohistochemical profile, and clinical course in two additional cases of this unusual variant of breast carcinoma. In the first case, the tumor had morphologic features suggestive of medullary carcinoma, and the patient is doing well 12 months after presentation. In the second case, the tumor was locally advanced at presentation with histologic features consistent with metaplastic carcinoma having squamous, sarcomatoid, and choriocarcinomatous elements. The patient presented with extensive multifocal metastases 6 months after the initial presentation and is not responding well to standard or experimental treatment regimen. Immunostaining for the beta subunit of human chorionic gonadotropin was localized mostly, but not entirely, to multinucleated syncytiotrophoblast-like giant cells within both tumors.

Can the number of cores with high-grade prostate intraepithelial neoplasia predict cancer in men who undergo repeat biopsy?

OBJECTIVES

To evaluate whether the presence of, or the number of cores containing, high-grade prostatic intraepithelial neoplasia (PIN) found in men who underwent initial extended multisite biopsy could predict which men would have prostate cancer on subsequent repeat biopsies.

METHODS

Between June 1997 and January 2003, 1086 men underwent initial prostate biopsy for early detection of prostate cancer using an extended multisite biopsy scheme. Of these, 175 men without cancer underwent at least one repeat biopsy (range one to three; median interval between biopsies, 3 months). Among these 175 patients, 47 had high-grade PIN on initial biopsy.

RESULTS

The initial extended biopsy identified cancer in 33.8% (367 of 1086) and high-grade PIN in 20.8% (226 of 1086). The incidence of high-grade PIN only in patients found to have cancer on initial biopsy was 29.7% (109 of 367). The presence of high-grade PIN was associated with concurrent prostate cancer at the initial biopsy (P <0.0001). Overall, repeat biopsy identified cancer in 18.3% of the 175 men. Of the 47 men with high-grade PIN, 5 (10.6%) were found to have cancer on repeat biopsy. The number of biopsy specimens positive for high-grade PIN on initial biopsy was not associated with the likelihood of prostate cancer on repeat biopsy. Multivariate logistic regression analysis showed that neither the presence of high-grade PIN nor the number of cores containing high-grade PIN on initial biopsy were predictors for prostate cancer on repeat biopsy.

CONCLUSIONS

The number of cores positive for high-grade PIN was not predictive for cancer on repeat biopsy.

Carcinoma of lung with rhabdoid features

Lung tumors with rhabdoid features, included as variants of large cell carcinoma in the 1999 World Health Organization classification of lung tumors, are rare and have an aggressive clinical course. We report 11 patients with primary lung tumors with rhabdoid features and review the literature on this uncommon tumor. We examined samples from 7 primary (6 resections, 1 biopsy) and 4 metastatic tumor samples. All specimens were stained with immunohistochemical stains for pancytokeratin (CK), cytokeratin 7 (CK7), cytokeratin (CK20), thyroid transcription factor-1 (TTF-1), and vimentin. The patients were 7 men and 4 women whose ages ranged from 35 to 70 years. Nine patients presented with respiratory symptoms, and 9 patients had a history of heavy smoking. One patient had TNM stage I tumor, 3 had stage III tumors, and 6 had stage IV tumors at presentation; tumor stage could not be determined in 1 patient. Histological examination of these tumors showed typical rhabdoid cells: large cells with abundant cytoplasm, a large eccentric nucleus with a central macronucleolus, and a rounded eosinophilic cytoplasmic inclusion that sometimes caused nuclear indentation. These cells constituted 10% to 90% of the tumor. The "parent" neoplasm was sarcomatoid carcinoma and adenocarcinoma in 4 cases each and was large cell undifferentiated carcinoma in 3 cases. Cytoplasmic staining in the rhabdoid cells was seen in 9 of 11 cases for CK, in 4 of 10 cases for CK7, and in all 11 cases for vimentin. Nuclear staining for TTF-1 in the rhabdoid cells was absent in all 11 cases, and cytoplasmic staining for CK20 was negative in the rhabdoid cells in all 10 cases studied. Of the 9 patients with available follow-up information, 8 died of disease, and 1 is alive with no evidence of disease 20 months after the initial diagnosis. We conclude that rhabdoid features can occur in a variety of lung tumors, including sarcomatoid carcinoma. Recognizing these lesions is important because of their possibly aggressive clinical course.

Ovarian yolk sac tumor associated with endometrioid carcinoma and mucinous cystadenoma of the ovary

The clinicopathologic and immunohistochemical findings of an unusual case of ovarian yolk sac tumor associated with endometrioid carcinoma and mucinous cystadenoma of the ovary are reported. The tumor was detected in a 51-year-old postmenopausal woman who presented with abdominal swelling and a pelvic mass. The patient underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy and omentectomy. The tumor was confined to the right ovary and measured 16.0 cm in greatest dimension. Microscopic examination revealed that the tumor had a yolk sac component associated with an endometrioid carcinoma, grade I, and a mucinous cystadenoma. A background of atypical endometriosis was noted. Immunoperoxidase studies showed that the yolk sac component stained diffusely with a cytokeratin cocktail and was focally positive for alpha-fetoprotein. It was negative for keratin 7. In contrast, the endometrioid carcinoma stained positive for keratin 7 in addition to the cytokeratin cocktail, but was negative for alpha-fetoprotein. After surgery, the patient received three cycles of chemotherapy. However, the disease progressed and the patient died 10 months after the diagnosis of the ovarian tumor.

Chromophobe renal cell carcinoma with sarcomatoid transformation

We present a rare case of a chromophobe renal cell carcinoma that progressed to a high-grade spindle cell sarcoma. The tumor affected a 50-year-old man who had presented with right upper quadrant discomfort and hematuria and subsequently underwent a right radical nephrectomy. Microscopically, the tumor was composed of two distinct components, a chromophobe renal cell carcinoma and a sarcomatoid component. The sarcomatoid component had exhibited aggressive behavior by spreading to a regional lymph node. This case report shows that chromophobe carcinoma can develop a sarcomatoid transformation with a high propensity for invasive growth and metastasis.

Benign myoepithelial tumors of the breast have immunophenotypic characteristics similar to metaplastic matrix-producing and spindle cell carcinomas

We immunohistochemically compared benign myoepithelial tumors (adenomyoepitheliomas [AMEs]) and metaplastic matrix-producing (MMP-CA) and spindle cell (MSC-CA) carcinomas of the breast to identify helpful diagnostic markers. Normal myoepithelial cells (MECs) consistently expressed cytokeratin, alpha-smooth muscle actin (SMA), myosin, S-100, CD10, and maspin. They were variably positive for vimentin and negative for epithelial membrane antigen (EMA), steroid receptors, p53, and HER-2/neu. MECs in AMEs less frequently expressed CD10 (4/8 [50%]) and myosin (6/8 [75%]) but frequently acquired characteristics of luminal cells, such as expression of EMA (5/8 [63%]) and steroid receptors (5/8 [63%]). No abnormal p53 or HER-2/neu expression was seen in AMEs. MMP-CA and MSC-CA were similar to AMEs in cytokeratin, vimentin, S-100, maspin, and HER-2/neu expression. MMP-CAs expressed less alpha-SMA (2/8 [25%]) and myosin (2/7 [29%]) and lacked estrogen receptor (0/9 [0%]). MSC-CAs were consistently CD10+ (4/4 [100%]) yet failed to express myosin (0/3 [0%]). p53 overexpression was seen frequently in MMP-CAs (4/8 [50%]) and MSC-CAs (1/3 [33%]). Benign myoepithelial mammary tumors differ immunophenotypically from normal MECs; a panel of immunohistochemical markers may be required to establish their myoepithelial origin. A similarly altered myoepithelial phenotype also is characteristic of metaplastic mammary carcinomas. The abnormal expression of oncogenes or antioncogenes, such as p53, may be more useful for distinguishing between those entities than the expression of the classic myoepithelial markers.

Vascular tumors of bone: A study of 17 cases other than ordinary hemangioma, with an evaluation of the relationship of hemangioendothelioma of bone to epithelioid hemangioma, epithelioid hemangioendothelioma, and high-grade angiosarcoma

Cases filed as vascular tumor of bone other than ordinary hemangioma were reviewed. They were included in the study if there was adequate histologic material and clinical information, clear evidence of bone origin, and at least 5 years follow-up. The study group comprised 17 cases, of which 13 were categorized as hemangioendothelioma of bone, 1 as epithelioid hemangioendothelioma, and 3 as high-grade angiosarcoma. Hemangioendothelioma of bone had growth patterns varying from vasoformative to solid, but well-formed vessels were present in at least some area in all cases. The cells generally had a rounded, epithelioid character, regular nuclei, and relatively few mitotic figures; occasional features included spindle cells and scattered enlarged, hyperchromatic or pleomorphic nuclei. Lymphoplasmacytic and eosinophilic inflammatory infiltrate ranged from prominent to slight or absent, and myxoid or hyaline stroma was never more than focal. Epithelioid hemangioma could not be separated from hemangioendothelioma of bone. The single epithelioid hemangioendothelioma for the most part had cords of relatively uniform epithelioid cells in a prominent myxoid stroma but focally demonstrated an angiosarcoma-like appearance, with irregular vascular spaces and marked nuclear pleomorphism. The high-grade angiosarcomas exhibited predominantly irregular vasoformation combined with solid areas, diffuse nuclear hyperchromatism and pleomorphism, and, in 2 cases, numerous mitotic figures (the third case had only a small biopsy and a postradiation amputation specimen). Of the hemangioendotheliomas of bone, 7 were unicentric and 6 were regionally multicentric either concurrently or sequentially. Three patients had intraosseous local recurrence, 2 had discontinuous regional skin or soft tissue involvement (including the popliteal artery in 1), and 1 had a solitary lung metastasis, but none died of tumor. The patient with epithelioid hemangioendothelioma had multicentric tumors in widely separated bones and died with liver and lung metastases. Two of the high-grade angiosarcomas were unicentric, and the third was regionally multicentric, with a popliteal artery-soft tissue component as well. All 3 of these patients died with metastases in various sites.