Novel fusion transcripts associate with progressive prostate cancer.

The mechanisms underlying the potential for aggressive behavior of prostate cancer (PCa) remain elusive. In this study, whole genome and/or transcriptome sequencing was performed on 19 specimens of PCa, matched adjacent benign prostate tissues, matched blood specimens, and organ donor prostates. A set of novel fusion transcripts was discovered in PCa. Eight of these fusion transcripts were validated through multiple approaches. The occurrence of these fusion transcripts was then analyzed in 289 prostate samples from three institutes, with clinical follow-up ranging from 1 to 15 years. The analyses indicated that most patients [69 (91%) of 76] positive for any of these fusion transcripts (TRMT11-GRIK2, SLC45A2-AMACR, MTOR-TP53BP1, LRRC59-FLJ60017, TMEM135-CCDC67, KDM4-AC011523.2, MAN2A1-FER, and CCNH-C5orf30) experienced PCa recurrence, metastases, and/or PCa-specific death after radical prostatectomy. These outcomes occurred in only 37% (58/157) of patients without carrying those fusion transcripts. Three fusion transcripts occurred exclusively in PCa samples from patients who experienced recurrence or PCaerelated death. The formation of these fusion transcripts may be the result of genome recombination. A combination of these fusion transcripts in PCa with Gleason's grading or with nomogram significantly improves the prediction rate of PCa recurrence. Our analyses suggest that formation of these fusion transcripts may underlie the aggressive behavior of PCa.

A validation study of quantum dot multispectral imaging to evaluate hormone receptor status in ductal carcinoma in situ of the breast.

The assessment of hormone receptors, including estrogen receptor and progesterone receptor, has become a standard practice in breast cancer management. However, the need for multiple sections to evaluate each receptor individually by conventional immunohistochemistry may preclude the analysis on some core biopsies with a limited amount of tumors. The aim of the study was to validate the quantitative analysis of nuclear markers estrogen receptor and progesterone receptor by quantum dot-based immunohistochemistry using a multispectral imaging system in ductal carcinoma in situ of the breast. Consecutive sections from a total of 17 cases of ductal carcinoma in situ with excisional biopsies or mastectomies were stained with conventional immunohistochemistry and quantum dot-based, single- and double-labeled immunohistochemistry for estrogen receptor and progesterone receptor. The semiquantitative results from double-labeled, quantum dot-based immunohistochemistry were compared with those from single-labeled, quantum dot-based immunohistochemistry as well as from conventional immunohistochemistry. There was good concordance between double- and single-labeled quantum dot-based immunohistochemistry, and quantum dot-based immunohistochemistry correlated well with conventional immunohistochemistry (Spearman correlation coefficient range from 0.884 to 0.958, P < .001). The findings proved the validity and accuracy of quantum dot-based multiplex, multispectral technique in detecting 2 tumor markers in the same cellular compartment simultaneously on a single slide. This technique may enhance our ability to assess multiple breast tumor markers in specimens with limited available tissue. However, several technical and logistic issues await significant improvement before this novel technique can be justified for routine clinical application.

Prostatic adenocarcinoma metastatic to pleomorphic liposarcoma, a "collision phenomenon": report of a case with review of pelvic collision tumors.

"Collision tumor" is an uncommon phenomenon characterized by coexistence of two completely distinct and independent tumors at the same site. Collision tumors have been reported in different sites in the body; however, these are particularly uncommon in the pelvic cavity. A 70-year-old man, with prior history of urothelial and prostate cancer, presented with a large pelvic mass detected on imaging studies. Pathological examination revealed a large liposarcoma with prostatic carcinoma embedded in it. Immunohistochemistry and florescence in situ hybridization studies were performed to reach to a conclusive diagnosis. To the best of our knowledge, this is the second case reported till date. We present the challenges encountered in the diagnosis of this case and review of pelvic collision tumors.

Adenosquamous carcinoma of the lung: a microdissection study of KRAS and EGFR mutational and amplification status in a western patient population.

Molecular testing of pulmonary adenocarcinomas for EGFR and KRAS mutations is becoming more common as tyrosine kinase inhibitor therapy is used for EGFR-mutated adenocarcinomas. Adenosquamous carcinomas represent a hybrid carcinoma, and there is no literature addressing the frequency of EGFR and KRAS mutations in this subset of lung carcinomas in Western populations. For this study, 23 adenosquamous carcinomas were microdissected with the glandular and squamous components analyzed for EGFR and KRAS mutations and EGFR amplification. In 3 cases (13%), there were EGFR mutations, with 2 having the identical mutation in the glandular and squamous elements. In 3 cases (13%), there were KRAS mutations in both histologic elements. Great heterogeneity existed in the rates of EGFR amplification in the 2 histologic components. Amplification was most common in both glandular and squamous components (11/23 [48%]). EGFR mutations occur in adenosquamous carcinoma in the same percentages as in conventional adenocarcinoma in the Western population. KRAS mutations are less common.

Renal oncocytoma: a comparative clinicopathologic study and fluorescent in-situ hybridization analysis of 73 cases with long-term follow-up.

Clinical studies have confirmed that renal oncocytoma (RO) is a benign neoplasm with excellent prognosis. In diagnostically challenging cases of renal oncocytic epithelial neoplasms, fluorescent in-situ hybridization (FISH) is increasingly being used and its ability to distinguish RO from chromophobe renal cell carcinoma (ChRCC) has been documented. In this study, we evaluated the differential diagnostic contribution of FISH in cases of RO.Clinicopathologic data and glass slides from 73 patients with RO were reviewed; 20 cases of ChRCC were included for comparison. FISH analysis of formalin-fixed, paraffin-embedded sections was performed using centromeric probes for chromosomes 1, 2, 7 and 17. FISH analysis revealed ROs had frequent loss of signal for chromosome 1 (56%) and 17 (44%). Tumors with more than one loss were common (41%) and 10% cases showed loss of all chromosomes examined. A total of 18% cases did not show any abnormality.Our study shows that chromosomal abnormalities in both ROs and ChRCCs are common with frequent loss of chromosomes 1 and 17. No association was found between overall patient survival and the extent of chromosomal abnormalities. FISH results, even those showing significant chromosomal abnormalities, should not alter the primarily morphology-based diagnosis of RO.

High rate of BRAF and RET/PTC dual mutations associated with recurrent papillary thyroid carcinoma.

PURPOSE: Papillary thyroid carcinoma (PTC), the most common thyroid malignancy, usually possesses BRAF mutation or rearranged in translation (RET)/PTC rearrangements. PTC usually possesses BRAF mutation or RET/PTC rearrangements. The mutation status of patients with recurrent PTC has never been characterized in a large population. EXPERIMENTAL DESIGN: Mutation status was determined in a cohort of 54 patients with recurrent PTC and analyzed for clinicopathologic relationships. BRAF and ras mutations were determined by PCR and sequencing of genomic DNA. RET/PTC rearrangements were analyzed by reverse transcription-PCR. RESULTS: BRAF mutation in exon 15 (V600E) was found in 42/54 (77.8%) recurrent PTC patients. The RET/PTC rearrangements were detected in 9 of 54 (16.7%) patients. In addition, 5 of 54 (9.3%) recurrent PTC patients had both a BRAF mutation and a RET/PTC rearrangement. The prevalence of tumors with dual mutations found in the recurrent population far exceeds the frequency historically reported for patients with primary PTC. Patients with dual mutations were significantly older (80% older than 45 years) than patients with a BRAF mutation alone (38% older than 45 years). CONCLUSIONS: Recurrent PTC is significantly associated with a predominant BRAF mutation. RET/PTC rearrangements, although commonly associated with primary PTCs in younger patients, are uncommonly found in recurrent PTC patients. In addition, the incidence of dual mutations was higher in patients with recurrent PTC than in those primary PTC, as reported by others.