Treatment-emergent neuroendocrine prostate cancer with a germline BRCA2 mutation: identification of a candidate reversion mutation associated with platinum/PARP-inhibitor resistance.

Neuroendocrine prostate cancer (NEPC) is a highly aggressive histologic subtype of prostate cancer associated with a poor prognosis. Its incidence is expected to increase as castration-resistant disease emerges from the widespread use of potent androgen receptor-targeting therapies, such as abiraterone and enzalutamide. Defects in homologous recombination repair genes, such as BRCA1/2, are also being increasingly detected in individuals with advanced prostate cancer. We present the case of a 65-yr-old man with a germline BRCA2 mutation who developed explosive treatment-emergent, small-cell neuroendocrine prostate cancer. He achieved a complete response to platinum-containing chemotherapy, but a limited remission duration with the use of olaparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, as maintenance therapy. Upon relapse, tumor genomic profiling revealed a novel 228-bp deletion in exon 11 of the BRCA2 gene. The addition of the anti-PD1 drug pembrolizumab to olaparib was ineffective. This case highlights the ongoing challenges in treating neuroendocrine prostate cancer, even in the setting of homologous recombination repair deficiency.

Fine-Needle Aspiration Biopsy of Intraocular Mass-Like Lesions.

OBJECTIVES: The purpose of this study was to evaluate the diagnostic performance of fine-needle aspiration (FNA) biopsy for intraocular mass-like lesions and its contributing factors. METHODS: Intraocular FNA cases were retrieved and reviewed along with histopathologic follow-ups, if available. The effects of rapid on-site evaluation (ROSE), repeated biopsy, and adjunct immunocytochemical studies on cytologic diagnoses were analyzed. RESULTS: Of 72 FNA biopsies from 63 patients, nondiagnostic biopsy was seen in 17 cases (24%), whereas a definitive diagnosis was rendered in 39 cases (54%). The cytologic diagnoses correlated well with histopathologic follow-ups with a concordance rate of 61%. Almost all nondiagnostic biopsies (16/17, 94%) were seen in cases in which ROSE was not performed. Of the 7 patients in whom biopsy was repeated, a definitive diagnosis was rendered in 4 cases (57%). Immunocytochemistry was performed in the majority of cases with a malignant diagnosis, especially in metastatic tumors (75%). CONCLUSIONS: Our data demonstrates that FNA is an effective tool for the diagnosis of intraocular tumors. ROSE, repeated biopsy, and adjunct immunocytochemistry can help reduce the nondiagnostic rate and/or enhance diagnosis of malignancy, further improving FNA diagnostic performance.

Peritoneal tuberculosis: A case report on a rare cause of tumor marker elevation.

Peritoneal tuberculosis (TB) is a rare extrapulmonary manifestation of TB with non-specific clinical characteristics which can produce test results mimicking malignancy and granulomatous peritonitis. This case describes a Filipino 59-year-old, nulliparous woman who was admitted with abdominal pain, ascites, and an elevated CA-125 level. Radiographically, peritoneal nodules were visualized and initial suspicion was high for malignancy. Following a bilateral salpingo-oophorectomy and peritoneal biopsy, histology was negative for malignancy but revealed non-caseating granulomas. She was discharged then readmitted with progressive abdominal pain, and a repeat laparoscopic biopsy yielded specimens with growth of acid-fast bacilli (AFB). A delay in diagnosis and treatment of tuberculous peritonitis increases mortality rates, making early diagnosis with laparoscopic biopsy of paramount importance in prompt diagnosis and initiation of therapy. This patient was initiated on standard anti-TB therapy and experienced no complications.

ATM-Mutated Pancreatic Cancer: Clinical and Molecular Response to Gemcitabine/Nab-Paclitaxel After Genome-Based Therapy Resistance.

Metastatic pancreatic cancer (PC) is an aggressive malignancy, with most patients deriving benefit only from first-line chemotherapy. Increasingly, the recommended treatment for those with a germline mutation in a gene involved in homologous recombination repair is with a platinum drug followed by a poly (ADP-ribose) polymerase (poly adenosine phosphate-ribose polymerase [PARP]) inhibitor. Yet, this is based largely on studies of BRCA1/2 or PALB2 mutated PC. We present the case of a 44-year-old woman with ATM-mutated PC who achieved stable disease as the best response to first-line fluorouracil, leucovorin, irinotecan, and oxaliplatin, followed by progression on a PARP inhibitor. In the setting of jaundice, painful hepatomegaly, and a declining performance status, she experienced rapid disease regression with the nonplatinum regimen, gemcitabine plus nab-paclitaxel. Both physical stigmata and abnormal laboratory values resolved, imaging studies showed a reduction in metastases and her performance status returned to normal. Measurement of circulating tumor DNA for KRAS G12R by digital droplet polymerase chain reaction confirmed a deep molecular response. This case highlights that first-line treatment with a platinum-containing regimen followed by PARP inhibition may not be the best choice for individuals with ATM-mutated pancreatic cancer. Additional predictors of treatment response are needed in this setting.

Identification of EGFR mutation, KRAS mutation, and ALK gene rearrangement in cytological specimens of primary and metastatic lung adenocarcinoma.

BACKGROUND: The identification of molecular alterations has an important therapeutic implication in patients with lung adenocarcinomas. In the current study, the authors evaluated their experience with the identification of epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation, and anaplastic lymphoma kinase (ALK) gene rearrangement using cytological specimens of primary and metastatic lung adenocarcinoma. METHODS: A total of 54 cases of lung adenocarcinomas (11 primary and 43 metastatic tumors) in which molecular tests were performed were retrieved. Molecular tests were performed on the cell block material of 19 effusions and 35 fine-needle aspirates. EGFR mutation was evaluated by polymerase chain reaction sequencing analysis of exons 18, 19, 20, and 21. KRAS mutation was tested using polymerase chain reaction-single-strand conformational polymorphism analysis of codons 12 and 13. ALK gene rearrangement was evaluated by fluorescence in situ hybridization using an ALK break apart probe. RESULTS: Molecular tests were successful in 49 of 54 cases (91%). Evaluation of EGFR mutation, KRAS mutation, and ALK gene rearrangement were performed in 49 cases, 14 cases, and 22 cases, respectively. EGFR mutations were found in 14 of 49 cases (29%), including 5 primary and 9 metastatic tumors. Three metastatic/recurrent adenocarcinomas demonstrated an additional EGFR T790M mutation that was not identified in the original specimens. KRAS mutation was detected in 3 of 14 cases (21%) including 1 primary and 2 metastatic tumors. ALK gene rearrangement was evident in 3 of 22 cases (14%), all of which were metastatic tumors. CONCLUSIONS: The results of the current study have demonstrated the feasibility of using cytological specimens for EGFR mutation, KRAS mutation, and ALK gene rearrangement analysis. Repeating molecular testing in metastatic/recurrent lung adenocarcinomas may uncover newly acquired molecular alterations.

Cytoplasmic vacuolization: an under-recognized cytomorphologic feature in endocrine tumors of the pancreas.

The diagnosis of pancreatic endocrine neoplasm (PEN) is often straightforward; however, cytomorphologic variants may impose a diagnostic challenge, particularly in small biopsies such as fine-needle aspiration (FNA). Here we describe prominent fine cytoplasmic vacuoles in three cases of PENs which were initially evaluated by endoscopic ultrasound-guided FNA. The clinicopathologic features and diagnostic pitfalls of this cytomorphologic variant were discussed. Awareness of this rare cytomorphologic feature with application of immunocytochemical studies is crucial for rendering an accurate diagnosis and avoiding diagnostic pitfalls.

Addenda in pathology reports: trends and their implications.

Addenda are typically used to report results of additional studies that are delayed relative to histopathologic studies. However, the frequency and pattern of use of addenda have not been previously reported. We studied the dynamics of addenda creation within the same month at 5-year intervals during a 15-year period at our institution. The number of addenda and type and impact of information communicated in addenda were assessed in the month of July in 1993, 1998, 2003, and 2008, and the possible role of addenda in quality improvement was evaluated. Cases with addenda increased from 0.9% in 1993 to 8.6% in 2008. In 5.6% of addenda, there was information that might have been better reported in an amendment, suggesting that criteria for amendments need to be universally implemented. Charting trends and types of addenda offered opportunities for quality improvement by identifying weaknesses in the workflow organization of the laboratory.

Papillary thyroid carcinomas with and without BRAF V600E mutations are morphologically distinct.

AIMS: The BRAF V600E mutation resulting in the production of an abnormal BRAF protein has emerged as the most frequent genetic alteration in papillary thyroid carcinomas (PTCs). This study was aimed at identifying distinctive features in tumours with and without the mutation. METHODS AND RESULTS: Thirty-four mutation-positive and 22 mutation-negative tumours were identified by single-strand conformation polymorphism of the amplified BRAF V600E region in the tumour DNA. Mutation-positive tumours were more common in patients older than 45 years (24/33, P = 0.05), in classic (23/30, P = 0.01), tall cell (4/5) and oncocytic/Warthin-like (2/2) variants of PTC, and in subcapsular sclerosing microcarcinomas (4/4). In contrast, all 12 follicular variants (P < 0.0001) and two diffuse sclerosing variants were negative for the mutation. Mutation-positive tumours displayed infiltrative growth (32/34, P = 0.02), stromal fibrosis (33/34, P < 0.001), psammoma bodies (17/34, P = 0.05), plump eosinophilic tumour cells (22/34, P = 0.01), and classic fully developed nuclear features of PTC (33/34, P = 0.0001). Encapsulation was significantly associated with mutation-negative tumours (15/22, P = 0.02). CONCLUSIONS: BRAF V600E mutation-positive and negative PTCs are morphologically different. Recognition of their morphology may help in the selection of appropriate tumours for genetic testing.

Pleomorphic adenoma arising in an incidental midline isthmic thyroid nodule: a case report and review of the literature.

Ectopic salivary gland tissue is common in the head and neck, usually associated with lymph nodes in lateral areas. It is rarely noted in the thyroid gland. Here we report the first case of a pleomorphic adenoma presenting as a midline nodule in the isthmus of thyroid in a 66-year-old man. We propose the possibility of origin in ectopic salivary gland tissue that may have aberrantly migrated with the median anlage from the foramen cecum in the base of the tongue during embryogenesis.

Primary myxopapillary ependymoma of the medulla: case report.

OBJECTIVE: Myxopapillary ependymoma is a subclassification of ependymoma that is thought to be nearly exclusive to the conus medullaris or filum terminale. Primary intracerebral or brainstem myxopapillary ependymomas are rare. CLINICAL PRESENTATION: An 8-year-old child presented with a 5-month history of nausea and vomiting and a 1-week history of headache. Magnetic resonance imaging revealed a nodular mass in the medulla with an associated cyst extending into the fourth ventricle. INTERVENTION: A suboccipital craniotomy was performed, and a gross total resection of the lesion and cyst was achieved. Histological examination confirmed the diagnosis of myxopapillary ependymoma. A discussion of other reported cases of extraspinal myxopapillary ependymomas is presented. CONCLUSION: This is the first report of a case of myxopapillary ependymoma, confirmed by histology, in the medulla. Although rare, myxopapillary ependymomas outside of the filum terminale do exist.

Immunohistochemical techniques to compare primary vs. metastatic mucinous carcinoma of the skin.

BACKGROUND: Primary and metastatic mucinous carcinomas in skin are histologically indistinguishable. Immunohistochemical panels help differentiate primary and metastatic adenocarcinoma of skin, but data regarding mucinous carcinoma is scant. METHODS: We stained five primary mucinous carcinomas, two mucinous carcinomas metastatic to skin and five primary breast and colon mucinous carcinomas with p63, CD15, CK5/6, CK7, CK20, calponin and D2-40 to identify patterns that might differentiate primary from metastatic disease. We also searched for myoepithelial cells in all cases. RESULTS: All cases of primary mucinous carcinoma of the skin were positive for CK7, 40% showed rare cells labeled for p63 and 20% of cases labeled focally for CK5/6. The breast mucinous carcinomas metastatic to the skin were negative for all markers except CK7, although 60% of primary breast carcinomas labeled for p63. Colon mucinous carcinoma labeled only for CK20. CONCLUSIONS: In a small subset of mucinous carcinomas (20% in this series), positive labeling for CK5/6 indicated primary cutaneous tumor. Staining with p63 also favored primary over metastatic disease. Myoepithelial cell layers were not consistently identified to enable the identification of primary disease.

Primary, non-exophytic, optic nerve germ cell tumors.

Tumors of the optic chiasm are relatively uncommon and usually associated with phakomatoses such as neurofibromatosis. Even more rare is the presentation of a primary, non-exophytic, isolated optic chiasm germ cell tumor (GCT). These tumors have imaging characteristics nearly indistinguishable from optic chiasmatic gliomas (OCGs). Herein we describe two cases of young men who presented with similar findings of progressive, painless visual loss and hypothalamic-pituitary-adrenal axis dysfunction including diabetes insipidus. Brain imaging was non-diagnostic and suggestive of an OCG. Pathology demonstrated GCTs in each case highlighting the importance of biopsy confirmation of the diagnosis. Both patients underwent a pterional craniotomy and sub-frontal approach to the optic chiasm. The chiasm was diffusely enlarged and discolored in each case without evidence of sellar, suprasellar or perichiasmatic pathology. Pathology demonstrated a malignant mixed GCT in the first patient and a germinoma in the second. This case series highlights the importance of tissue biopsy for patients with progressive symptoms from optic chiasm tumors. Furthermore, this is the first report of a primary, non-exophytic malignant mixed GCT. As the treatment regimens differ widely between optic chiasm GCTs and chiasm gliomas, tissue diagnosis is important.

ElrA and AUF1 differentially bind cyclin B2 mRNA.

In Xenopus embryos, maternal cyclins drive the first 12 cell divisions after which several cyclins are terminally degraded, including cyclin B2. Cyclin B2 disappearance is due to transcription-mediated mRNA deadenylation at the midblastula transition, when transcription initiates and the cell cycle lengthens. To further define the mechanism, we characterized proteins capable of binding cyclin B2 3'UTR. We show that ElrA and AUF1 compete for binding to regions containing cytoplasmic polyadenylation elements (CPEs), with AUF1 binding increasing at the midblastula transition. Deletion of both CPEs abrogates polyadenylation but has no effect on deadenylation or binding of ElrA or AUF1. Overexpression of ElrA or AUF1 does not alter cyclin B2 mRNA stability. These results show that ElrA and AUF1 bind to cyclin B2 mRNA independent of CPEs and function by binding other elements.

Type I autoimmune hepatitis presenting with acute liver failure in the setting of wild mushroom ingestion.

Type I autoimmune hepatitis usually has an indolent presentation and course, and is classically thought of as a disease of young women, but can in fact occur across all age ranges. Although its etiology remains unclear, it is hypothesized that an environmental antigen may trigger the disease in a genetically susceptible individual. Here, we report the unusual case of a woman in her seventh decade who presented with acute liver failure as her initial manifestation of autoimmune hepatitis, and who had been a long-time ingestor of hand-picked, wild mushrooms.

Antisense knockdown of cyclin E does not affect the midblastula transition in Xenopus laevis embryos.

In Xenopus laevis embryos, cyclin E protein remains constitutively high throughout the first 12 cell cycles following fertilization until the onset of the midblastula transition (MBT) (after the 12(th) cell cycle) when it undergoes a dramatic reduction. The disappearance of cyclin E at the MBT occurs independently of active cell cycle progression, zygotic transcription, protein synthesis and the nuclear to cytoplasmic ratio. This has suggested that cyclin E is part of an autonomous maternal timer that regulates the onset of the MBT. To determine how constitutively high levels of cyclin E are maintained prior to the MBT and to investigate if the reduction in cyclin E protein affects the timing of the MBT, we have knocked down endogenous cyclin E mRNA using an N,N-diethyl-ethylene-diamine modified antisense oligonucleotide targeted to its open reading frame. We report that maintenance of high levels of cyclin E protein before the MBT is due to a balance between ongoing translation and proteolytic degradation. In support of our antisense experiments, polysome analysis demonstrates that cyclin E mRNA is associated with the translated fraction prior to the MBT. Furthermore, knockdown of cyclin E was not associated with defects in the timing of developmental events. Our data suggests that cyclin E is not required for the later cell cycles of embryonic development and that the pathway effecting downregulation of cyclin E rather then cyclin E degradation itself may be part of a maternal timer that affects the onset of the MBT.

Purification, characterization and cloning of tensilin, the collagen-fibril binding and tissue-stiffening factor from Cucumaria frondosa dermis.

The inner dermis of the sea cucumber, Cucumaria frondosa, is a mutable collagenous tissue characterized by rapid and reversible changes in its mechanical properties regulated by one or more protein effectors that are released from neurosecretory cells. One such effector, tensilin, is a collagen-fibril binding protein, named for its ability to induce dermis stiffening. Tensilin was purified using an affinity column constructed from C. frondosa collagen-fibrils. The protein migrates as a single band on SDS-PAGE (Mr approximately 33 kDa) and has an isoelectric point of 5.8. Equilibrium sedimentation experiments suggest a molecular mass of approximately 28.5-29.4 kDa. Carbohydrate analysis of tensilin revealed no measurable sugar content. The molar amount of tensilin was determined to be 0.38% that of collagen and 47% that of stiparin, a constitutive matrix glycoprotein. A full-length cDNA clone for tensilin was obtained from a C. frondosa inner dermis cDNA expression library. Predicted properties derived from the deduced peptide sequence were in agreement with those of the native protein. A noted feature of tensilin's deduced peptide sequence, particularly in its N-terminal domain, is its homology to tissue inhibitor of metalloproteinases. Tensilin's C-terminal tail has no known homology to other proteins but contains a putative collagen-fibril binding site.