Liquid chromatographic-tandem mass spectrometric determination of amprenavir (agenerase) in serum/plasma of human immunodeficiency virus type-1 infected patients receiving combination antiretroviral therapy.

A selective assay method for quantitation of amprenavir (agenerase) in human immunodeficiency virus type-1 infected patient serum or plasma using liquid chromatography-tandem mass spectrometry (LC-MS-MS) is described. Amprenavir and an internal standard (reserpine) are extracted by liquid-liquid extraction and chromatographically separated by a reversed-phase C18-analytical column. The triple quadrupole LC-MS-MS system is operated in the positive-ion mode and multiple reaction monitoring is used for drug quantitation. The method has been validated over the range of 0.05-10.0 microg/ml. The RSDs for the intra-day and inter-day determinations ranged from 5.3 to 6.1% and from 4.7 to 6.2%, respectively. The average assay accuracy at two different concentrations ranged from 96.0 to 103.0% and the extraction recovery of amprenavir was 90.8%. The lower limit of quantitation was 0.05 microg/ml. Using a short microbore column, the analysis was completed in less than 5 min.

Myiasis secondary to Sermatobia hominis (human botfly) presenting as a long-standing breast mass.

A case of a 54-year-old woman who presented with a breast mass is reported. Histologically, a chronic granulomatous inflammatory response was observed. The response was associated with an organism diagnosed as a fly larva, Dermatobia hominis (human botfly). The incidence of myiasis, infestation by fly larvae, presenting as a long-standing breast mass and mimicking a neoplasm is extremely rare, especially in the United States.

Rhabdomyosarcoma mimicking acute leukemia in an adult: report of a case with histologic, flow cytometric, cytogenetic, immunohistochemical, and ultrastructural studies.

A case of a 25-year-old man who presented with low back, knee, and hip pain with bruising, leukocytosis, and thrombocytopenia is reported. Histopathologic and flow cytometric studies revealed a malignant neoplasm, which was thought to be consistent with an unusual type of acute leukemia. Subsequent immunohistochemical studies revealed diffuse bone marrow involvement by rhabdomyosarcoma, demonstrated by positivity for desmin and muscle-specific actin. In addition, the diagnosis of metastatic rhabdomyosarcoma was confirmed with cytogenetic and ultrastructural studies. The incidence of rhabdomyosarcoma, a disease usually seen in childhood, presenting with extensive bone marrow involvement and mimicking acute leukemia in an adult is extremely rare. This case highlights the need to consider rhabdomyosarcoma in the differential diagnosis in patients who present with a leukemic picture and atypical blasts that lack the usual hematopoietic markers.

Tumor cell contamination of bone marrow harvest products: clinical consequences in a cohort of advanced-stage breast cancer patients undergoing high-dose chemotherapy.

Patients undergoing high-dose chemotherapy (HDC) with autologous stem cell rescue (ASCR) may have tumor cells inadvertently infused if their stem cell product is tumor contaminated. We used an immunocytochemical (ICC) method to analyze 31 histologically negative bone marrow (BM) specimens taken from women with advanced-stage breast cancer at the time of BM harvest before HDC. All 31 patients were treated on one of three consecutive HDC protocols and received BM or BM and peripheral stem cells (PSC) as ASCR. Six of 26 evaluable patients had ICC-detectable contaminating tumor cells in their BM harvests. These 6 patients had a trend toward decreased overall survival compared with those patients without ICC-detectable tumor cells (17 months median versus 25+ months, p = 0.11, log rank test for those patients achieving complete response, CR, from HDC). The sites of relapse in the ICC-positive and ICC-negative groups were not notably different when analyzed for new sites versus previous sites of disease. Therefore, our retrospective analysis of a small cohort of patients suggests that the infusion of tumor cells in breast cancer patients undergoing HDC may confer a poor prognosis. Relapse patterns however suggest failure both in new sites and in sites of previous disease. Additional studies in expanded patient populations are needed to explore further the role of tumor cell infusion in ASCR and the possible clinical benefits of tumor cell removal procedures.

Immunocytochemical detection of tumor cells in bone marrow and peripheral blood stem cell collections from patients with ovarian cancer.

High-dose chemotherapy (HDC) followed by autologous hematopoietic reconstitution is an experimental treatment option for patients with epithelial ovarian cancer. However, the incidence of occult ovarian tumor cell involvement in autologous bone marrow (BM) or peripheral blood stem cell (PBSC) autografts has not been widely investigated. We used a highly sensitive immunocytochemical (ICC) procedure that detects occult blood-borne tumor micrometastases. We analyzed 24 BM specimens (15 obtained during therapy and 9 harvest samples) and seven PBSC specimens from 22 patients with ovarian cancer. Overall, ICC analysis detected immunostained tumor cells in 10 of 23 evaluable BM specimens (43%) from 9 of 19 patients (47%). One of 9 (11%) harvest samples contained tumor cells. Only one of the 10 ICC-positive BM specimens had tumor cells detected by routine histopathological analysis. ICC-detectable tumor cells were cleared from the marrow of two patients during chemotherapy. None of the seven PBSC specimens contained tumor cells. We conclude that ovarian cancer micrometastases have the potential to contaminate BM, as is also the case in patients with other epithelial malignancies. In the limited number of specimens analyzed, PBSC harvests appeared to provide a less tumor-contaminated source of hematopoietic stem cells for autologous transplantation.

Immunohistologic detection of prostate cancer pelvic lymph node micrometastases: correlation to preoperative serum prostate-specific antigen.

OBJECTIVE: To test the hypothesis that prostate cancer lymph node (LN) micrometastases, undetected by standard histology, might be found using sensitive immunohistologic methods and may correlate to preoperative prostate-specific antigen (PSA) levels. METHOD: Archival paraffin blocks of pelvic lymphadenectomy specimens from radical prostatectomy were blindly submitted for immunostaining using pan-cytokeratin monoclonal antibody SB-3, as well as antibodies directed against PSA. Automated immunostaining was performed on a Ventana Medical Systems 320 immunostainer. As a positive control, 7 cases with known nodal metastases by standard histology were blindly analyzed and all has detectable micrometastases by this methodology. RESULTS: For 13 patients with PSA < 10.1 (8%) had LN micrometastases detected. For 10 patients with PSA between 10 and 20 and for 9 patients with PSA > 20, no occult metastases were detected. We did find previously undetected prostate cancer (CaP) LN micrometastases in 1 of 32 (3%) clinically localized prostate cancer patients who had undergone radical prostatectomy. In many LNs, cytokeratin stains cross-reacted and stained individual plasma cells, whereas in the positive metastatic case, a cluster/nest of CaP cells were reactive. To the unfamiliar observer, the pitfall of false-positive results because of nonspecific cytokeratin staining must be considered. These results are in exact agreement with another recent study which also found only a 3 percent incidence of unsuspected pelvic lymph node micrometastases in clinically localized CaP utilizing similar methods. CONCLUSIONS: Our hypothesis was not substantiated: LN micrometastases were uncommon and did not correlate to serum PSA. Unlike studies with breast cancer, occult micrometastatic nodal disease not appreciated by standard methods appears to be uncommon in clinically localized prostatic carcinoma.

Incidental metastatic mammary carcinoma in a total knee arthroplasty patient.

Incidental metastatic breast carcinoma was discovered by histologic examination in a total knee arthroplasty (TKA) patient. A 70-year-old woman was evaluated for increasing debilitating pain in the right knee. A radiograph demonstrated only degenerative changes. Degenerative changes were noted in the gross and microscopic examination of the knee specimen. The unsuspected focus of poorly differentiated adenocarcinoma was suggestive of mammary carcinoma. A mass in the right breast then was subsequently noted on reexamination. Mastectomy showed infiltrating adenocarcinoma with metastases to axillary lymph nodes, and diffuse involvement of the skeleton was demonstrated with a bone scan. This case emphasizes the importance of a meticulous history and a complete medical examination before surgery, detailed examinations of the excised knee and joint fragments by a pathologist after a TKA operation. Malignancy can be missed with only gross specimen evaluations and radiographs.

Perineurioma of the kidney. Report of a case with histologic, immunohistochemical, and ultrastructural studies.

We report a perineurioma of the kidney. A 66-year-old woman had a renal mass discovered as an incidental finding during the evaluation of hypertension and proteinuria. This neoplasm radiographically mimicked renal cell carcinoma, but the diagnosis of perineurioma was confirmed with histologic and ultrastructural studies. Perineurioma is a recently described, rare, benign tumor of the peripheral nervous system composed of perineurial cells. Histologically, the differential diagnosis includes low-grade fibromyxoid sarcoma and other myxoid tumors.

Ossifying seminoma of the testis.

A 55-year-old Hispanic man presented with a large testicular mass with metastases to pelvic and retroperitoneal lymph nodes and bones. Computed tomographic scans revealed calcifications in the testis and lymph nodes. The orchiectomy specimen showed a seminoma with extensive ossifications. The amount of bone formation, believed to represent a degenerative phenomenon, is extremely unusual and, to the best of my knowledge, has not been presented in the literature.

Urethral T-cell lymphoma as the initial manifestation of the acquired immune deficiency syndrome.

We report the first case (to our knowledge) of a primary urethral T-cell lymphoma as the initial manifestation of the acquired immune deficiency syndrome. A 36-year-old white homosexual man with antibodies to human immunodeficiency virus type 1 was evaluated for a hemorrhagic urethral discharge. A 2-cm fleshy, polypoid mass in the bulbous urethra was removed, and the diagnosis of small non-cleaved cell (non-Burkitt's) lymphoma was made. Immunohistochemical analysis confirmed that the tumor was of T-cell lineage. Patients with the acquired immunodeficiency syndrome have an increased incidence of lymphomas, particularly extranodal high-grade non-Hodgkin's lymphomas. Primary urethral lymphomas are extremely rare, with only a handful of cases reported in the literature. This rare form and site of lymphoma should be considered in patients with the acquired immunodeficiency syndrome who have genitourinary symptoms.

Hyperprolactinemia in a patient with a pituitary and an ovarian dermoid tumor: case report.

A patient with galactorrhea, amenorrhea, and hyperprolactinemia caused by a dermoid tumor of the pituitary gland is presented. The patient had a prior history of an ovarian dermoid tumor. The pathology of dermoid tumors is discussed along with the management of pituitary tumor-associated hyperprolactinemia. This is the first reported case of an intracranial and an ovarian dermoid tumor occurring in the same patient.

Cryptosporidial and cytomegaloviral hepatitis and cholecystitis.

We describe an immunosuppressed patient with enteric cryptosporidiosis who developed combined cryptosporidial and cytomegaloviral hepatitis and cholecystitis as well as Enterobacter cloacae cholecystitis. To our knowledge, the presence of Cryptosporidium in a liver biopsy specimen has not previously been reported.