GLI1-Altered Mesenchymal Tumors With ACTB or PTCH1 Fusion: A Molecular and Clinicopathologic Analysis

Mesenchymal tumors with GLI1 fusions or amplifications have recently emerged as a distinctive group of neoplasms. The terms GLI1-altered mesenchymal tumor or GLI1-altered soft tissue tumor serve as a nosological category, although the exact boundaries/criteria require further elucidation. We examined 16 tumors affecting predominantly adults (median age: 40 years), without sex predilection. Several patients had tumors of longstanding duration (>10 years). The most common primary site was soft tissue (n = 9); other sites included epidural tissue (n = 1), vertebra (n = 1), tongue (n = 1), hard palate (n = 1), and liver (n = 1). Histologically, the tumors demonstrated multinodular growth of cytologically uniform, ovoid-to-epithelioid, occasionally short spindled cells with delicate intratumoral vasculature and frequent myxoid stroma. Mitotic activity ranged from 0 to 8 mitoses/2 mm2 (mean 2). Lymphovascular invasion/protrusion of tumor cells into endothelial-lined vascular spaces was present or suspected in 6 cases. Necrosis, significant nuclear pleomorphism, or well-developed, fascicular spindle-cell growth were absent. Half demonstrated features of the newly proposed subset, "distinctive nested glomoid neoplasm." Tumors were consistently positive for CD56 (n = 5/5). A subset was stained with S100 protein (n = 7/13), SMA (n = 6/13), keratin (n = 2/9), EMA (n = 3/7), and CD99 (n = 2/6). Tumors harbored ACTB::GLI1 (n = 15) or PTCH1::GLI1 (n = 1) fusions. The assays used did not capture cases defined by GLI1 amplification. We also identified recurrent cytogenetic gains (1q, 5, 7, 8, 12, 12q13.2-ter, 21, and X). For patients with available clinical follow-up (n = 8), half were disease free. Half demonstrated distant metastases (lungs, bone, or soft tissue). Of cases without follow-up (n = 8), 2 were known recurrences, and 1 was presumed metastasis. Our results imply a more aggressive biological potential than currently reported. Given the possibility for metastasis and disease progression, even in cytologically bland, nested tumors, close clinical surveillance, akin to that for sarcoma management, may be indicated. The term GLI1-altered mesenchymal tumor with malignant potential is proposed.

Expanding Our Knowledge of Molecular Pathogenesis in Histiocytoses: Solitary Soft Tissue Histiocytomas in Children With a Novel CLTC::SYK Fusion

The histiocytoses comprise a histopathologically and clinically diverse group of disorders bearing recurrent genomic alterations, commonly involving the BRAF gene and mitogen-activated protein kinase pathway. In the current study, a novel CLTC :: SYK fusion in 3 cases of a histopathologically distinct histiocytic neoplasm arising as solitary soft tissue lesions in children identified by next-generation sequencing and fluorescence in situ hybridization is described. Morphologically, all 3 neoplasms were composed of sheets of cells with round-oval nuclei and vacuolated eosinophilic cytoplasm but, in contrast to classic juvenile xanthogranuloma (JXG), Touton giant cells were absent. A separate cohort of classic JXG cases subsequently profiled by fluorescence in situ hybridization were negative for the presence of a CLTC::SYK fusion suggesting that CLTC::SYK fusion-positive histiocytoma is genetically and histologically distinct from JXG. We postulate that the CLTC::SYK fusion leads to aberrant activation of the SYK kinase, which is involved in variable pathways, including mitogen-activated protein kinase. The identification of a novel CLTC::SYK fusion may pave the way for the development of targeted therapeutic options for aggressive disease.

Method of Tissue Acquisition Affects Success of Comprehensive Genomic Profiling in Lung Cancer

CONTEXT.—

Multiple procedural techniques can be used to obtain tissue to create a formalin-fixed, paraffin-embedded specimen for comprehensive genomic profiling (CGP) in lung cancer. The literature is mixed on whether the procedure affects CGP success.

OBJECTIVE.—

To examine whether biopsy procedure affects lung cancer CGP success.

DESIGN.—

This was a cross-sectional study of all patients with lung cancer whose specimens were submitted for CGP between January and February 2020. Multiple quality control metrics were used to determine whether cases were successfully profiled.

RESULTS.—

In all, 3312 samples were identified. Overall, 67.5% (2236 of 3312) of samples were obtained from biopsies, 13.0% (432 of 3312) from fine-needle aspirations (FNAs), 9.7% (321 of 3312) from resections, 5.3% (174 of 3312) from fluid cytology cell blocks, and 4.5% (149 of 3312) from bone biopsies. Overall, 70.1% (2321 of 3312) of cases passed CGP, 15.4% (510 of 3312) of cases were released as qualified reports, and 14.5% (481 of 3312) of cases failed CGP. Resection samples were the most likely to be successfully sequenced, failing in only 2.8% (9 of 321) of instances, while fluid cytology specimens were the least likely, failing in 23.0% (40 of 174) of instances. Biopsy (14.5% [324 of 2236]), FNA (18.5% [80 of 432]), and bone biopsy (18.8% [28 of 149]) specimens failed at intermediate frequencies. On multivariate logistic regression analysis of CGP success on specimen type, fluid cytology (odds ratio [OR], 0.08; 95% CI, 0.03-0.19), biopsy (OR, 0.25; 95% CI, 0.11-0.52), FNA (OR, 0.14; 95% CI, 0.06-0.32), and bone biopsy (OR, 0.07; 95% CI, 0.03-0.17) specimens had decreased odds of CGP success relative to resection samples. Among patients with successfully sequenced samples, 48.0% were eligible for at least 1 therapy, based on a companion diagnostic or National Comprehensive Cancer Network biomarker.

CONCLUSIONS.—

The method of tissue acquisition was an important preanalytic factor that determined whether a sample would be successfully sequenced and whether a clinically actionable genomic alteration would be detected.

Genomic landscape of lymphatic malformations: a case series and response to the PI3Kα inhibitor alpelisib in an N-of-1 clinical trial

Background

Lymphatic malformations (LMs) often pose treatment challenges due to a large size or a critical location that could lead to disfigurement, and there are no standardized treatment approaches for either refractory or unresectable cases.

Methods

We examined the genomic landscape of a patient cohort of LMs (n = 30 cases) that underwent comprehensive genomic profiling using a large-panel next-generation sequencing assay. Immunohistochemical analyses were completed in parallel.

Results

These LMs had low mutational burden with hotspot PIK3CA mutations (n = 20) and NRAS (n = 5) mutations being most frequent, and mutually exclusive. All LM cases with Kaposi sarcoma-like (kaposiform) histology had NRAS mutations. One index patient presented with subacute abdominal pain and was diagnosed with a large retroperitoneal LM harboring a somatic PIK3CA gain-of-function mutation (H1047R). The patient achieved a rapid and durable radiologic complete response, as defined in RECIST1.1, to the PI3Kα inhibitor alpelisib within the context of a personalized N-of-1 clinical trial (NCT03941782). In translational correlative studies, canonical PI3Kα pathway activation was confirmed by immunohistochemistry and human LM-derived lymphatic endothelial cells carrying an allele with an activating mutation at the same locus were sensitive to alpelisib treatment in vitro, which was demonstrated by a concentration-dependent drop in measurable impedance, an assessment of cell status.

Conclusions

Our findings establish that LM patients with conventional or kaposiform histology have distinct, yet targetable, driver mutations.

Funding

R.P. and W.A. are supported by awards from the Levy-Longenbaugh Fund. S.G. is supported by awards from the Hugs for Brady Foundation. This work has been funded in part by the NCI Cancer Center Support Grants (CCSG; P30) to the University of Arizona Cancer Center (CA023074), the University of New Mexico Comprehensive Cancer Center (CA118100), and the Rutgers Cancer Institute of New Jersey (CA072720). B.K.M. was supported by National Science Foundation via Graduate Research Fellowship DGE-1143953.

Clinical trial number

NCT03941782.

HPV51-associated Leiomyosarcoma: A Novel Class of TP53/RB1-Wildtype Tumor With Predilection for the Female Lower Reproductive Tract

Inactivating mutations in tumor suppressor genes TP53 and RB1 are considered central drivers in leiomyosarcomas (LMSs). In high-risk human papillomavirus (HPV)-related tumors, a similar functional outcome is achieved through oncoproteins E6 and E7, which inactivate the p53 and RB1 proteins, respectively. Here, we hypothesized that HPV infection could provide an alternative mechanism for tumorigenesis in a subset of TP53/RB1-wildtype LMS. We evaluated tumor samples from 2585 consecutive unique patients carrying a diagnosis of gynecologic or soft tissue LMS. Tumor DNA and available RNA were analyzed by hybrid-capture-based next-generation sequencing/comprehensive genomic profiling of 406 genes and transcripts (FoundationOneHeme). Of the initial 2585 cases, we excluded 16 based on the presence of molecular alterations that are considered defining for sarcomas other than LMS. In the remaining 2569 cases, we searched for LMS that were TP53/RB1-wildtype (n=486 of 2569; 18.9%). We also searched LMS tumors for HPV sequences that we then classified into genotypes by de novo assembly of nonhuman sequencing reads followed by alignment to the RefSeq database. Among TP53/RB1-wildtype LMS, we identified 18 unique cases harboring HPV sequences. Surprisingly, most (n=11) were HPV51-positive, and these 11 represented all HPV51-positive tumors in our entire LMS database (n=11 of 2569; 0.4%). The absence of genomic alterations in TP53 or RB1 in HPV51-positive LMS represented a marked difference from HPV51-negative LMS (n=2558; 0% vs. 72% [P<0.00001], 0% vs. 53% [P=0.0002]). In addition, compared with HPV51-negative LMS, HPV51-positive LMS were significantly enriched for genomic alterations in ATRX (55% vs. 24%, P=0.027) and TSC1 (18% vs. 0.6%, P=0.0047). All HPV51-positive LMS were in women; median age was 54 years at surgery (range: 23 to 74 y). All known primary sites were from the gynecologic tract or adjacent anogenital area, including 5 cases of vaginal primary site. Histology was heterogeneous, with evaluable cases showing predominant epithelioid (n=5) and spindle (n=5) morphology. In situ hybridization confirmed the presence of high-risk HPV E6/E7 mRNA in tumor cells in three of three evaluable cases harboring HPV51 genomic sequences. Overall, in our pan-LMS analysis, HPV reads were identified in a subset of TP53/RB1-wildtype LMS. For all HPV51-associated LMS, the striking absence of any detectable TP53 or RB1 mutations and predilection for the female lower reproductive tract supports our hypothesis that high-risk HPV can be an alternative tumorigenic mechanism in this distinct class of LMS.

Prevalence of UV Mutational Signatures Among Cutaneous Primary Tumors

This cross-sectional study examines the prevalence of UV alteration signatures in a pan-cancer next-generation sequencing database.

OUP accepted manuscript

Background

Materials and Methods

Results

Conclusions

CYLD-mutant cylindroma-like basaloid carcinoma of the anus: a genetically and morphologically distinct class of HPV-related anal carcinoma

Rare reports of anal carcinoma (AC) describe histologic resemblance to cutaneous cylindroma, but mutations in the tumor suppressor CYLD, the gene responsible for familial and sporadic cylindromas, have not been systematically investigated in AC. Here, we investigate CYLD-mutant AC, focusing on molecular correlates of distinct histopathology. Comprehensive genomic profiling (hybrid-capture-based DNA sequencing) was performed on 574 ACs, of which 75 unique cases (13%) harbored a CYLD mutation. Clinical data, pathology reports, and histopathology were reviewed for each CYLD-mutant case. The spectrum of CYLD mutations included truncating (n = 50; 67%), homozygous deletion (n = 10; 13%), missense (n = 16; 21%), and splice-site (n = 3; 4%) events. Compared with CYLD-wildtype AC (n = 499), CYLD-mutant ACs were significantly enriched for females (88% vs. 67%, p = 0.0001), slightly younger (median age 59 vs. 61 years, p = 0.047), and included near-universal detection of high-risk HPV sequences (97% vs. 88%, p = 0.014), predominantly HPV16 (96%). The CYLD-mutant cohort also showed significantly lower tumor mutational burden (TMB; median 2.6 vs. 5.2 mut/Mb, p < 0.00001) and less frequent alterations in PIK3CA (13% vs. 31%, p = 0.0015). On histopathologic examination, 73% of CYLD-mutant AC (55/75 cases) showed a striking cylindroma-like histomorphology, composed of aggregates of basaloid cells surrounded by thickened basement membranes and containing characteristic hyaline globules, while only 8% of CYLD-wildtype tumors (n = 34/409) contained cylindroma-like hyaline globules (p < 0.0001). CYLD-mutant carcinomas with cylindroma-like histomorphology (n = 55) showed significantly lower TMB compared with CYLD-mutant cases showing basaloid histology without the distinctive hyaline globules (n = 14) (median 1.7 vs. 4.4 mut/Mb, p = 0.0058). Only five CYLD-mutant cases (7%) showed nonbasaloid conventional squamous cell carcinoma histology (median TMB = 5.2 mut/Mb), and a single CYLD-mutant case showed transitional cell carcinoma-like histology. Within our cohort of ACs, CYLD mutations characterize a surprisingly large subset (13%), with distinct clinical and genomic features and, predominantly, a striking cylindroma-like histopathology, representing a genotype-phenotype correlation which may assist in classification of AC.

Melanoma with in-frame deletion of MAP2K1: a distinct molecular subtype of cutaneous melanoma mutually exclusive from BRAF, NRAS, and NF1 mutations

While the genomics of BRAF, NRAS, and other key genes influencing MAP kinase (MAPK) activity have been thoroughly characterized in melanoma, mutations in MAP2K1 (MEK1) have received significantly less attention and have consisted almost entirely of missense mutations considered secondary oncogenic drivers of melanoma. Here, we investigated melanomas with in-frame deletions of MAP2K1, alterations characterized as MAPK-activating in recent experimental models. Our case archive of clinical melanoma samples with comprehensive genomic profiling by a hybrid capture-based DNA sequencing platform was searched for MAP2K1 genetic alterations. Clinical data, pathology reports, and histopathology were reviewed for each case. From a cohort of 7119 advanced melanomas, 37 unique cases (0.5%) featured small in-frame deletions in MAP2K1. These included E102_I103del (n = 11 cases), P105_A106del (n = 8), Q58_E62del (n = 6), I103_K104del (n = 5), I99_K104del (n = 3), L98_I103del (n = 3), and E41_F53del (n = 1). All 37 were wild type for BRAF, NRAS, and NF1 genomic alterations ("triple wild-type"), representing 2.0% of triple wild-type melanomas overall (37/1882). Median age was 66 years and 49% were male. The majority arose from primary cutaneous sites (35/37; 95%) and demonstrated a UV signature when available (21/25; 84%). Tumor mutational burden was typical for cutaneous melanoma (median = 9.6 mut/Mb, range 0-35.7), and frequently mutated genes included TERTp (63%), CDKN2A (46%), TP53 (11%), PTEN (8%), APC (8%), and CTNNB1 (5%). Histopathology revealed a spectrum of appearances typical of melanoma. For comparison, we evaluated 221 cases with pathogenic missense single nucleotide variants in MAP2K1. The vast majority of melanomas with missense SNVs in MAP2K1 showed co-mutations in BRAF (58%), NF1 (23%), or NRAS (18%). In-frame deletions in MAP2K1, previously shown in experimental models to be strongly MAPK-activating, characterized a significant subset of triple wild-type melanoma (2.0%), suggesting a primary oncogenic role for these mutations. Comprehensive genomic profiling of melanomas enables detection of this alteration, which may have implications for potential therapeutic options.

Primary myxoid and epithelioid mesenchymal tumor of the kidney with a novel GLI1-FOXO4 fusion

To our knowledge, we describe the first mesenchymal tumor with a novel GLI1-FOXO4 fusion gene. This well-circumscribed kidney tumor displayed variably myxoid and epithelioid histologic features with a focally nodular growth pattern. The tumor cells showed bland, round to ovoid nuclei, with no overt high-grade features. The tumor showed focal immunopositivity for smooth muscle actin and Melan-A, which raised the possibility of a relationship with a perivascular epithelioid cell tumor. The clinical and morphologic features appear distinct from other reported neoplasms harboring GLI1 or FOXO4 gene rearrangements. The patient underwent radical nephrectomy and is without evidence of disease during a relatively short clinical follow-up period. However, the features of this tumor likely warrant long-term follow-up to monitor for the possibility of a late recurrence or metastasis. In addition to reporting this novel fusion-positive tumor, we also provide a brief review of GLI1 and FOXO4 gene functions in both normal and neoplastic contexts.

Molecular profiling of mesonephric and mesonephric-like carcinomas of cervical, endometrial and ovarian origin

•

KRAS mutation is a major driver in mesonephric and mesonephric-like carcinomas of cervical, endometrial or ovarian origin.

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ARID1A and PIK3CA mutations were also identified in endometrial and ovarian mesonephric-like carcinomas.

•

Peripheral blood ctDNA liquid biopsy may detect mutations in recurrent and/or metastatic mesonephric carcinomas.

Mesonephric carcinoma is a rare cancer that most often arises within the cervix, and less frequently, in the ovary and endometrium. A retrospective search of our CLIA-certified and CAP-accredited reference molecular laboratory database (Foundation Medicine, Inc.) identified 20 mesonephric or mesonephric-like, cervical (n = 10), endometrial (n = 5), ovarian (n = 4) or peri-bladder (n = 1) carcinomas that had undergone comprehensive genomic profiling via next generation sequencing. Activating KRAS mutations were present in 90%, 18 of 20 cases, including G12V (n = 7), G12D (n = 6), G12A (n = 3) and G12C (n = 2). Other recurrent alterations were identified in ARID1A (25%), PIK3CA (20%), CTNNB1 (15%), TP53 (10%), MLL2 (10%) and CDKN2A (10%). One KRAS wild-type case had a GATA3 mutation as the sole alteration, while the second KRAS wild-type case had an EGFR exon 20 insertion D770_N771insSVD alteration. All tumors were negative for HPV DNA, microsatellite instability, high tumor mutational burden and homologous recombination deficiency. A circulating tumor DNA (ctDNA) liquid biopsy from peripheral blood, which was performed 6 years after original solid tumor resection in one patient with suspected lung metastasis, revealed concordance of KRAS alteration, gains of chromosomes 1q, 2, 10, 12 and 20, plus new TP53 alterations in the liquid biopsy compared to the original sample. KRAS G12 mutation is major driver of mesonephric and mesonephric-like carcinomas, with less frequent contribution by ARID1A and PIK3CA pathways in tumors of non-cervical origin. ctDNA liquid biopsy may be useful in detecting mutations in recurrent or metastatic patients, who may potentially be eligible for trials against emerging targeted therapies.

Melanomas with activating RAF1 fusions: clinical, histopathologic, and molecular profiles

A subset of melanomas is characterized by fusions involving genes that encode kinases. Melanomas with RAF1 fusions have been rarely reported, mostly in clinical literature. To investigate this distinctive group of melanomas, we searched for melanomas with activating structural variants in RAF1, utilizing our case archive of clinical samples with comprehensive genomic profiling (CGP) by a hybrid capture-based DNA sequencing platform. Clinical data, pathology reports, and histopathology were reviewed for each case. RAF1 breakpoints, fusion partners, and co-occurring genetic alterations were characterized. From a cohort of 7119 melanomas, 40 cases (0.6%) featured fusions that created activating structural variants in RAF1. Cases with activating RAF1 fusions had median age of 62 years, were 58% male, and consisted of 9 primary tumors and 31 metastases. Thirty-nine cases were cutaneous primary, while one case was mucosal (anal) primary. Primary cutaneous melanomas showed variable architectures, including wedge-shaped and nodular growth patterns. Cytomorphology was predominantly epithelioid, with only one case, a desmoplastic melanoma, consisting predominantly of spindle cells. RAF1 5' rearrangement partners were predominantly intrachromosomal (n = 18), and recurrent partners included MAP4 (n = 3), CTNNA1 (n = 2), LRCH3 (n = 2), GOLGA4 (n = 2), CTDSPL (n = 2), and PRKAR2A (n = 2), all 5' of the region encoding the kinase domain. RAF1 breakpoints occurred in intron 7 (n = 32), intron 9 (n = 4), intron 5 (n = 2), and intron 6 (n = 2). Ninety-eight percent (n = 39) were wild type for BRAF, NRAS, and NF1 genomic alterations (triple wild type). Activating RAF1 fusions were present in 2.1% of triple wild-type melanomas overall (39/1882). In melanomas with activating RAF1 fusions, frequently mutated genes included TERTp (62%), CDKN2A (60%), TP53 (13%), ARID2 (10%), and PTEN (10%). Activating RAF1 fusions characterize a significant subset of triple wild-type melanoma (2.1%) with frequent accompanying mutations in TERTp and CDKN2A. CGP of melanomas may improve tumor classification and inform potential therapeutic options, such as consideration of specific kinase inhibitors.

Vulvar Squamous Cell Carcinoma: Comprehensive Genomic Profiling of HPV+ Versus HPV- Forms Reveals Distinct Sets of Potentially Actionable Molecular Targets

PURPOSE

Vulvar squamous cell carcinoma (vSCC) encompasses two predominant variants: one associated with detectable high-risk strains of human papillomavirus (hrHPV) and a second form often occurring in the context of chronic dermatitis in postmenopausal women. Genomic assessment of a large-scale cohort of patients with aggressive vSCC may identify distinct mutational signatures.

MATERIALS AND METHODS

Tumor samples from a total of 280 patients with vSCC underwent hybridization capture with analysis of up to 406 cancer-related genes. Human papillomavirus (HPV) sequences were detected by de novo assembly of nonhuman sequencing reads and aligned to the RefSeq database. Immunohistochemistry for programmed death-ligand 1 (PD-L1) was assessed.

RESULTS

One hundred two of 280 vSCCs (36%) contained hrHPV sequences, predominantly HPV 16 (88%). The HPV-positive (HPV+) group was significantly younger (median age, 59 v 64 years; P = .001). Compared with HPV-negative (HPV–) vSCCs, HPV+ tumors showed more frequent pathogenic alterations in PIK3CA (31% v 16%; P = .004), PTEN (14% v 2%; P < .0001), EP300 (14% v 1%; P < .0001), STK11 (14% v 1%; P < .0001), AR (5% v 0%; P = .006), and FBXW7 (10% v 3%; P = .03). In contrast, HPV– vSCCs showed more alterations in TP53 (83% v 6%; P < .0001), TERTp (71% v 9%; P < .0001), CDKN2A (55% v 2%; P < .0001), CCND1 amplification (22% v 2%; P < .0001), FAT1 (25% v 4%; P < .0001), NOTCH1 (19% v 6%; P = .002), and EGFR amplification (11% v 0%; P < .0001), as well as a higher rate of 9p24.1 (PDL1/PDL2) amplification (5% v 1%) and PD-L1 immunohistochemistry high-positive tumor staining (33% v 9%; P = .04).

CONCLUSION

Comprehensive molecular profiles of vSCC vary considerably with hrHPV status and may inform patient selection into clinical trials. Sixty-one percent of HPV+ vSCCs had a pathogenic alteration in the PI3K/mTOR pathway, whereas HPV– vSCCs showed alterations in TP53, TERTp, CDKN2A, CCND1, and EGFR, and biomarkers associated with responsiveness to immunotherapy.

Trichodysplasia spinulosa: Case reports and review of literature

Trichodysplasia spinulosa (TS) is a rare skin condition caused by trichodysplasia spinulosa-associated polyomavirus (TSPyV). It affects immunosuppressed patients, and <50 cases have been reported. The majority of these cases are seen in solid organ transplant recipients. TS often poses a diagnostic and therapeutic challenge because of its rarity and resemblance with other skin conditions. Several forms of treatment are usually tried prior to establishing a definitive diagnosis. Oral valganciclovir and topical cidofovir have been found to give the best results and hence are the most commonly used agents once the diagnosis is established. Here, we present two cases with a review of literature of TS in solid organ transplant recipients, focusing on time to develop the condition post-transplant, immunosuppression regimen used, and treatment initiated both before and after a definitive diagnosis.

Increased tumor purity and improved biomarker detection using precision needle punch enrichment of pathology specimen paraffin blocks: Method validation and implementation in a prospective clinical trial

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Background: While many sequencing assays may be geared for short variants (SV), more complex biomarkers such as genomic loss of heterozygosity (gLOH) score, also referred to as homologous recombination deficiency (HRD) score, require higher tumor purity for confident detection. Practical methods to increase tumor nuclei percentage (TN%) from pathology specimens are needed to achieve biomarker results to maximize patient matching to approved therapies and/or clinical trial enrollment. Methods: Tumor purity of specimens was determined by the computational analysis pipeline component of the FDA-approved NGS assay, FoundationOneCDx. In the validation study, specimen purities for each tissue block were compared following either no enrichment (UnE, n=46), pathologist-directed enrichment by straight razor blade (RBE, n=30) or precision needle punch (NPE, n=47). Post-enrichment H&E slides confirmed target region sampled for the NPE arm. Based upon validation data, the needle punch process was implemented for the Lung-MAP prospective clinical trial (LM-NPE). TN% was compared between the first 55 tested LM-NPE specimens and the validation study to assess performance on real-world samples outside of a controlled validation experiment. Results: The mean computational TN% in the 4 groups were: UnE: 33%; RBE: 30%; NPE: 52%; and LM-NPE: 48%. In the validation study, NPE had significantly higher purity than both UnE and RBE (p<0.001); in the trial arm, LM-NPE performed equivalently to NPE (p=0.344). Based upon a 30% tumor purity cutoff, gLOH could be determined for 52% UnE, 50% RBE, 89% NPE and 71% LM-NPE. Comparing NPE and LM-NPE groups reveals no statistical difference in Pass/Fail rates for gLOH determination (p=0.883; Fisher’s Test). Conclusions: Precision needle punch cores from tissue blocks have elevated tumor purity, and consequently, a greater number of successful gLOH determinations. Moreover, this process is rapid and inexpensive. Precision punches may constitute best practice with respect to enriching tumor cells from low-purity specimens for biomarker detection in a routine laboratory specimen-processing setting. [Table: see text]

Cutaneous Metastasis of Gastroenteropancreatic Neuroendocrine Tumors (GEP-Nets)

BACKGROUND

Gastroenteropancreatic neuroendocrine tumors are neoplasms commonly found within the gastrointestinal tract that originate from endocrine cells. These are slow progressive tumors and often metastasize to other elements of the gastrointestinal tract including the liver. Consequently, these tumors release hormones including serotonin and/or histamine that are responsible for the symptoms including intermittent flushing and diarrhea. Metastasis of gastroenteropancreatic neuroendocrine tumors, although rare, is possible and may extend to local lymph nodes and viscera.

CASE REPORT

Our patient was a 69-year-old female who initially presented with postprandial abdominal pain, nausea, vomiting, and later was diagnosed with gastroenteropancreatic neuroendocrine tumors following surgical resection in 2014. Restaging after surgery showed regional lymph node involvement and hepatic metastasis. Of note she did not have a pre-operative computed tomography scan. She was started on octreotide, and later switched to lanreotide. In the interim, she did not have any positive findings on serial octreoscans depicting the skin lesion that was performed in the interim period every six months. However, she noticed a cutaneous mass in the upper right flank mass in 2016, which was followed up by a dermatologist. In 2017, the mass grew in size and hence biopsied which showed neuroendocrine tumors consistent with her primary tumor.

DISCUSSION

Gastroenteropancreatic neuroendocrine tumors often metastasize to lymph nodes and liver but rarely can involve the skin and present as firm papules as found in our patient. Cutaneous metastasis of gastroenteropancreatic neuroendocrine tumors often has high morbidity and mortality and is usually associated with a primary lesion in the bronchopulmonary system. However, as demonstrated in this case report, cutaneous metastasis can originate from the gastrointestinal tract, including the small intestine as well.

Characterization of tumor mutation burden (TMB) and microsatellite instability (MSI) interplay for gastroesophageal adenocarcinoma (GA) and colorectal carcinoma (CRC)

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Background: Tumor genomic instability is positively correlated with immunotherapy response. It confers different tumor phenotypes, including high TMB (TMB-H) and high MSI (MSI-H). Recently the US Food and Drug Administration approved MSI-H phenotype as a biomarker for immunotherapy, highlighting its importance, but also bringing up the question of how TMB as another promising biomarker is going to add value in the field. Here, we characterized TMB and MSI profiles to better understand the potential TMB contribution and identify genomic markers for it. Methods: 734 solid tumor were collected, with 462 CRC, and 272 GA samples. Large panel Next-Generation Sequencing assay with the ability to determine TMB and MSI, was performed on each sample. Based on the TMB and MSI status, patients were grouped into four categories: THMH (TMB-H and MSI-H), THMS (TMB-H and MSI-Stable), TLMH (TMB-Low and MSI-H), and TLMS (TMB-Low and MSI-Stable). To identify genes that are related to the interplay of TMB and MSI, Random Forest and Lasso Regression models were applied to identify genes most predictive of the four categories. Results: TMB and MSI are highly correlated in our cohort of CRC and GA tumors. However, 5.8% CRC and 12.9% GA samples are under THMS (Table 1). In these samples, alternate DNA repair pathways are potentially dysregulated, including the nucleotide excision pathway (ATRX, APC), DNA double strand break repair (FANCF, SETD2), and the previously described proofreading pathway (POLD1). We hypothesize that these patients may also derive clinical benefit from immunotherapy. Conclusions: Immunotherapy benefits could be extended to more patients by jointly measuring MSI and TMB. The corresponding marker genes could also be extended beyond the commonly known POLE/POLD1 genes. Orthogonal validation by Whole Exome Sequencing data of the in silico mined marker genes is currently underway. [Table: see text]

Characterization of biomarkers to immune checkpoint blockade therapy across solid tumors

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Background: Immune checkpoint blockade (ICB) therapy has been effective patients with solid tumors. Currently, tumor expression of programmed death-ligand 1 (PD-L1) is clinically used as a biomarker of predicted response to ICBs in non-small cell lung cancer (NSCLC). However, across solid tumors, only a subset of patients benefit from ICBs, so there is need to identify other biomarkers to predict response to ICB. We investigated the use of large panel next generation sequencing (NGS) to characterize biomarkers to ICBs across solid tumors. Methods: NGS and PD-L1 immunohistochemistry (IHC) was performed on a series of solid tumors. NGS analysis included detection of single nucleotide polymorphisms (SNPs), insertions and deletions (indels), copy number variation (CNV), and gene-fusions in 435 cancer-related genes, microsatellite instability (MSI), tumor mutational burden (TMB) based on non-synonymous SNPs, and HPV16/18 and EBV viral status. Genomic alterations in previously reported biomarkers of response to ICBs were assessed. Results: 143 solid tumors were analyzed with NGS and PD-L1 IHC. The samples included 80 NSCLC, 15 colorectal carcinoma, 8 cutaneous melanoma, 6 breast carcinoma, and 34 other solid tumors. The mean TMB varied by tumor type, with the highest in melanoma. The frequency of PD-L1 expression was higher in NSCLC and melanoma compared to colorectal carcinoma. The relationship between PD-L1 expression and the other biomarkers varied by tumor type (Table 1). Positive association (+); Negative association (-): No association (None). Conclusions: We characterized biomarkers to ICBs across a range of solid tumors. We found tumor-specific differences in the mean TMB and frequency of PD-L1 expression. We also found tumor-specific differences in the associations between PD-L1 and other potential biomarkers, including KRAS, NRAs, HRAs, BRAF, and EGFR mutation status. We found no correlation between PD-L1 expression and MSI and viral status. NGS is an efficient platform for analysis of biomarkers in solid tumors.[Table: see text]

Clinical application of a cancer genomic profiling assay to guide precision medicine decisions

Aim:

Develop and apply a comprehensive and accurate next-generation sequencing based assay to help clinicians to match oncology patients to therapies.

Materials & methods:

The performance of the CANCERPLEX^® assay was assessed using DNA from well-characterized routine clinical formalin-fixed paraffin-embedded (FFPE) specimens and cell lines.

Results:

The maximum sensitivity of the assay is 99.5% and its accuracy is virtually 100% for detecting somatic alterations with an allele fraction of as low as 10%. Clinically actionable variants were identified in 93% of patients (930 of 1000) who underwent testing.

Conclusion:

The test's capacity to determine all of the critical genetic changes, tumor mutation burden, microsatellite instability status and viral associations has important ramifications on clinical decision support strategies, including identification of patients who are likely to benefit from immune checkpoint blockage therapies.

Comprehensive genomic profiling to merge precision medicine with immunotherapy

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Background: Immunotherapy is rapidly emerging as one of the most promising therapeutic options in clinical oncology. However, not all patients will respond to immune-oncology drugs and diagnostic assays are urgently needed to identify biomarkers that predict response to these therapies. We developed an assay that utilizes next generation sequencing data to simultaneously determine different types of somatic changes in tumors. The assay was designed, in part, to facilitate identification of cancer patients most likely to respond to immunotherapies by detecting 1) CD274 (PD-L1) copy number alterations, 2) viral infections (HPV16/18 and EBV), 3) microsatellite instability (MSI), and 4) tumor mutation burden. Methods: We developed a 435-gene panel assay (CancerPlex) with the goal of identifying all the genomic changes that inform treatment decisions with the highest possible accuracy. We thoroughly evaluated the performance of the assay using reference samples that represent all classes of genetic variation, including SNPs, indels, copy number changes, rearrangements, HPV/EBV infection and MSI. FFPE clinical samples were also evaluated to assess the ability of the assay to detect genetic variation in complex, heterogeneous tumors. Results: The assay has excellent performance, with a mean sensitivity of 99.4% and specificity of 99.9% for detecting somatic mutations with an allele fraction as low as 10%. The assay identified the MSI status of colorectal tumors with the same sensitivity as immunohistochemistry but with greater sensitivity than PCR. We also showed that calculating tumor mutation burden using the 435-gene panel predicts response to pembrolizumab as effectively as using whole exome sequencing. Among 892 patients across all tumor types, 6.8% were identified as candidates for immunotherapy based upon high tumor mutation burden and/or MSI status. Conclusions: The capacity of the 435-gene panel to determine all of the critical genetic changes, tumor mutation burden, MSI status, CD274 (PD-L1) CNVs, and HPV/EBV status has important ramifications for patient treatment strategies, including identification of patients who are more likely to benefit from immune checkpoint inhibitor therapies.

Histopathologic spectrum of hypersensitivity reactions associated with anti-CD52 therapy (alemtuzumab)

BACKGROUND

Alemtuzumab is a humanized monoclonal antibody directed against CD52, a cell surface antigen on B and T lymphocytes, and used to treat B-cell chronic lymphocytic leukemia and cutaneous T-cell lymphoma. Skin rash is a common adverse reaction following treatment with alemtuzumab. However, the clinicopathologic features and immunologic basis for the reaction have not been previously reported.

METHODS

Our hospital's electronic pathology database was searched for cases with documentation of 'alemtuzumab' or 'anti-CD52' in the clinical history provided by either the ordering physician or the pathologist. Clinical and histopathologic review of the cases was performed.

RESULTS

Five patients with cutaneous T-cell lymphoma (CTCL) or chronic lymphocytic leukemia (CLL) were treated with alemtuzumab, and developed pruritic, erythematous papules and plaques. Histopathology of the skin lesions revealed subacute spongiotic dermatitis with multifocal parakeratosis, endothelial activation and perivascular lymphocytic infiltrate. Eosinophils were not a prominent feature.

CONCLUSIONS

We describe the clinicopathologic features of a novel hypersensitivity reaction to alemtuzumb, and hypothesize it may be due to an immunologic response precipitated by the persistence of resident memory T-cells (T_RM ) in the skin. Our findings raise awareness for a novel reaction pattern and guide the histopathologic interpretation of lesions which may clinically mimic residual or recurrent cutaneous lymphoproliferative disorders.

Assessment of Melanocyte Density in Anorectal Mucosa for the Evaluation of Surgical Margins in Primary Anorectal Melanoma

OBJECTIVES

Accurate histopathologic evaluation of surgical resection margins for anorectal melanoma (AM) is diagnostically challenging but essential to clinical management. We studied intraepithelial melanocyte density and growth pattern in anorectal mucosa and BRAF V600E mutation status in AM compared to controls.

METHODS

Histomorphology and melanocytic immunostains, microphthalmia transcription factor (MITF) and human melanoma black 45 (HMB45), were evaluated. Utility of VE1 immunostaining for determination of BRAF V600E mutation status was studied.

RESULTS

Immunostains aid in the distinction between "trailing" melanoma in situ (MIS) and benign melanocyte hyperplasia (BMH), by facilitating assessment of melanocyte density, and evaluation of nuclear atypia and growth pattern. While respective melanocyte densities overlapped, "trailing" MIS could be distinguished by melanocyte nuclear atypia and near confluent growth, compared to the banal cytology and scattered growth of BMH.

CONCLUSIONS

In the histopathologic assessment of AM resections, MITF and HMB45 immunostains aid in distinguishing between "trailing" MIS and BMH, by highlighting melanocyte density, nuclear atypia, and growth pattern, with the latter two being reliable features. VE1 showed nonspecific immunopositivity in anorectal glandular epithelium, a potential diagnostic pitfall when assessing BRAF mutation status.

Melanoma arising in a nevus of Ito: novel genetic mutations and a review of the literature on cutaneous malignant transformation of dermal melanocytosis

Dermal melanocytosis refers to a spectrum of benign melanocytic proliferations that includes Mongolian spot, nevus of Ota and nevus of Ito. These lesions most commonly occur in persons of Asian or African descent and are often present at birth or develop during childhood. Very rarely, dermal melanocytoses undergo malignant transformation. There have been only 13 reports in the literature of primary cutaneous melanoma arising in dermal melanocytoses. We report a case of a Chinese woman with melanoma arising in a congenital nevus of Ito. We performed targeted next-generation sequencing of the tumor which revealed mutations of GNAQ and BAP1, suggesting that alterations in these two genes led to malignant transformation of the nevus of Ito. We also provide a summary of reports in the literature regarding primary cutaneous melanoma arising in the context of dermal melanocytosis.

Dermatopathologic manifestations of intravenous drug use

BACKGROUND

The rate of intravenous drug use (IVDU) has been increasing nationally; however, cutaneous manifestations of IVDU have infrequently been investigated. We report a series of the clinicopathological correlation of IVDU in the skin.

METHODS

A search of surgical pathology files between the years 2000 and 2014 was performed for cutaneous specimens from patients with a reported history of IVDU for which the histopathological findings could not be attributed to another etiology. Ten cases for which slides were available were included in the study.

RESULTS

Patients had an average age of 39.7 years and had active or recent history of IVDU. Clinical impressions included ulcer, granulomatous dermatitis, vasculitis, pyoderma gangrenosum and hyperpigmentation at injection sites. Histopathology revealed leukocytoclastic vasculitis (n = 2), dermal pigment deposition (n = 3), non-specific ulceration/scarring (n = 4) and necrobiosis lipoidica-like dermatitis (n = 1). No infectious etiology or polarizable foreign material was identified in any case.

CONCLUSIONS

Cutaneous manifestations of IVDU should be considered in the differential as an etiology for dermatopathologic findings in high-risk patients. We report histopathological findings beyond the scope of those most commonly associated with IVDU. We aim to raise awareness of the cutaneous manifestations of IVDU to improve clinicopathological correlation and patient management in light of the ongoing epidemic.

Peutz-Jeghers syndrome: a critical look at colonic Peutz-Jeghers polyps

Peutz-Jeghers syndrome is an autosomal dominant condition characterized by gastrointestinal hamartomatous polyps. The pathologic identification of a Peutz-Jeghers polyp is integral to the diagnosis of this syndrome that often remains undiagnosed until after these polyps are identified. Histologically, Peutz-Jeghers polyps are characterized by a distinctive arborization of smooth muscle within the lamina propria. Colonic Peutz-Jeghers polyps, however, may mimic mucosal prolapse polyps or virtually any colonic polyp that undergoes prolapse. In this paper, we explore the morphological features of colonic Peutz-Jeghers polyps and the diagnostic challenges associated with these polyps. Colonic polyps from patients with Peutz-Jeghers syndrome were identified (n=34). The control cohort, included mucosal prolapse polyps (n=5), hyperplastic polyps (n=10) and tubular adenomas with prolapse (n=9), ganglioneuromatous polyps (n=2) and juvenile polyps (n=14). Intramucosal smooth muscle fibers were identified in all classes of polyps. Twenty-three of the 34 colonic Peutz-Jeghers polyps were characterized by lobulated clusters of colonic crypts. On immunohistochemistry, desmin-positive smooth muscle fibers were seen surrounding these lobules. This lobular organization of the crypts was not identified in mucosal prolapse polyps and hyperplastic polyps or tubular adenomas with prolapse; only one of the 14 juvenile polyps showed this pattern of reactivity on a desmin stain. Our data suggests that the histologic hallmark of colonic Peutz-Jeghers polyps is the lobular organization of the crypts, and that an arborizing pattern of smooth muscle proliferation is neither sensitive nor a specific marker of colonic Peutz-Jeghers polyps. The presence of desmin-positive smooth muscle fibers surrounding the lobules is a helpful diagnostic feature of colonic Peutz-Jeghers polyps, and facilitates the distinction of these polyps from non-Peutz-Jeghers polyps with prolapse-like changes.

Spray-dried lipid-hyaluronan-polymethacrylate microparticles for drug delivery in the peritoneum

Application of controlled release technology to the peritoneum would allow for sustained drug levels. However, some polymeric systems either create adhesions, or rapidly exit the peritoneum; neither result is desirable. Here we have produced particles based on sphyngomyelin, a phospholipid that occurs naturally in the peritoneum, along with hyaluronic acid and the polymethacrylate Eudragit E100 (to modulate drug release). Particles with a low proportion of E100 (5% (w/w); "high SPM") release albumin rapidly over 2 days, then more slowly; increasing the E100 to 20% (w/w; high "E100") slowed drug release markedly. When injected in the murine peritoneum, high SPM particles were disseminated as free particles, without forming collections. There was a mild inflammatory response but no formation of adhesions. High E100 particles formed collections in all animals, with an intense inflammatory response. Even so, there were very few adhesions. These results suggest that microparticulate formulations can be produced that have acceptable drug-releasing properties and are suitable for use in the peritoneum from the standpoint of biocompatibility.

Tetrodotoxin for prolonged local anesthesia with minimal myotoxicity

Conventional local anesthetics such as bupivacaine cause considerable myotoxicity and neurotoxicity, whereas tetrodotoxin (TTX) does not. Tetrodotoxin combined with bupivacaine or vasoconstrictors produces long-duration nerve blockade. To assess whether these prolonged blocks can be produced without increased myotoxicity, Sprague-Dawley rats were injected with bupivacaine, TTX, and both, or TTX plus epinephrine. Median durations of thermal nociceptive blockade were, respectively, 188, 401, 882, and 972 min. On dissection 4 days later, all tissues appeared macroscopically pristine. Muscle injury was at most mild to moderate in all animals, and the muscle injury scores for the combination formulations were not higher than for bupivacaine alone. Similarly, in differentiated cells from a myoblast cell line (C2C12), TTX caused either no or minimal worsening of cell viability from bupivacaine at 2 or 7 days. Epinephrine did not worsen TTX's relatively minimal cytotoxicity. Tetrodotoxin may thus be useful in producing prolonged nerve block with minimal myotoxicity and perhaps neurotoxicity.

Biodegradable polymeric microspheres and nanospheres for drug delivery in the peritoneum

Drug delivery to the peritoneum is hampered by rapid clearance, and could be improved by application of controlled release technology. We investigated the suitability for peritoneal use of micro- and nanoparticles of poly(lactic-co-glycolic) acid (PLGA), a biodegradable polymer with generally excellent biocompatibility commonly used for controlled drug release. We injected 90 kDa PLGA microparticles, 5-250 microm in diameter, into the murine peritoneum, in dosages of 10-100 mg (n=3-5 per group). We found a high incidence of polymeric residue and adhesions 2 weeks after injection (e.g., 50 mg of 5-microm microparticles caused adhesions in 83% of animals). Histology revealed chronic inflammation, with foreign body giant cells prominent with particles>5 microm in diameter. Five micrometer microspheres made from 54, 57, and 10 kDa PLGA (gamma irradiated) caused fewer adhesions (16.7%) with a similar incidence of residue. Nanoparticles (265 nm) of 90 kDa PLGA also caused much fewer adhesions (6.3% of animals), possibly because they were cleared from the peritoneum within 2 days, and sequestered in the spleen and liver, where foamy macrophages were noted. The effect of sterilization technique on the incidence of adhesion formation is also studied.

Site 1 sodium channel blockers prolong the duration of sciatic nerve blockade from tricyclic antidepressants

Many recent reports in the literature address the local anesthetics efficacy of tricyclic antidepressants (TCAs). Here we investigated whether nerve block from TCAs is prolonged by site 1 sodium channel blockers such as tetrodotoxin and saxitoxin, which are known to prolong block from conventional local anesthetics. Tetrodotoxin and saxitoxin greatly prolonged block from TCAs. For example, the median duration of thermal nociceptive blocks for 10 mM amitriptyline, nortriptyline and doxepin were 0, 0, and 124 min; co-injection with 20 microM TTX (median block duration=0), yielded blocks lasting 404, 325, and 697 min, respectively. Co-injection of 12 microM saxitoxin (median block duration=0) with 10 mM amitriptyline resulted in a thermal nociceptive block duration of 373 min. Co-injection of 7.7 mM bupivacaine and 7.7 mM amiptriptyline did not result in block prolongation. Systemic (subcutaneous) delivery of tetrodotoxin or amitriptyline did not result in prolongation of block from the other class of drug injected at the sciatic nerve. In TCA-containing formulations, motor blockade was consistently longer than thermal nociceptive block; motor blockade was also prolonged by tetrodotoxin and saxitoxin. In summary site 1 sodium channel blockers prolong the duration of TCAs via a locally mediated mechanism.

Identification of novel genes expressed during spermatogenesis in stage-synchronized rat testes by differential display

The molecular mechanism regulating spermatogenesis at different developmental stages remains largely unknown. In a vitamin A-deficiency (VAD) rat model, five distinct histologically defined, stage-synchronized testes: (i) resting spermatogonia and preleptotene spermatocytes at Day 0 of post-vitamin A treatment (PVA); (ii) early pachytene spermatocytes at Day 7 PVA; (iii) late pachytene at Day 15 PVA; (iv) round spermatids at Day 25 PVA; and (v) elongated spermatids at Day 35 PVA were used to study gene expression profiles by mRNA differential display. Twenty-four differentially expressed cDNA fragments were identified and cloned; oligonucleotide sequence analyses indicated that there are 12 novel gene sequences, half of which share no apparent match in current GenBank/EMBL databases. Other 12 VAD clones share sequence homology to membrane channel and transport, transcription and translation, cell cycle and morphogenesis, inducer and transducer, surface or secreted glycoproteins or enzymes, and other miscellaneous molecules. Semi-quantitative RT-PCR analyses against different stages of VAD testes demonstrated: (i) restricted expression of VAD1.2 and 1.3 (novel) on Day 25 PVA when round spermatids form; (ii) escalating pattern of VAD12 (Cx43) in Sertoli cells; and (iii) relative constant levels of VAD4 (A5D3), VAD26.1 (ribonuclease), and VAD27 (GRP8) in spermatogenesis.

Delivery and scavenging system for small animal inhalational anesthesia

BACKGROUND

Inhalational agents have been widely used for anesthesia in laboratory animals. However, the safe use of inhalational agents in small laboratory animals has been limited by the lack of a suitable and effective scavenging system for the removal of waste anesthetic gases. The aim of the present study is to develop an anesthetic system that can be manufactured using common household and laboratory items.

MATERIALS AND METHODS

An anesthetic system was designed for rats weighing from 300 to 350 g. A face mask for the rat was made by cutting off the distal part of a 50-ml centrifuge tube. A scavenging hood was made from a transparent plastic food storage box. Exhaust of anesthetic gases from the scavenger hood was facilitated by fitting an outlet connected to a pump. Four experienced researchers or technicians tested the scavenger hood.

RESULTS

In 79.2% of the trials the participants could smell halothane when the pump from the scavenger system was not operational. However, when the pump was switched on, halothane was detected only 16.7% of the time (P < 0.001).

CONCLUSION

We have developed a simple and effective method of delivering inhalational anesthesia to small laboratory animals and of removing waste anesthetic gases.

Expression of vascular endothelial growth factor in third-trimester placentas is not increased in growth-restricted fetuses

OBJECTIVE

Vascular endothelial growth factor (VEGF) is considered the growth factor that stimulates vasculogenesis and angiogenesis. Recent studies have demonstrated its role in regulating placental growth and invasion. Its expression can be upregulated by hypoxia. Intrauterine growth restriction (IUGR) is thought to be associated with inadequate placental perfusion, which might result from a failure in the development of the villous vascular network. Our present study was undertaken to examine the relationship between VEGF expression and IUGR in pregnancies with preserved umbilical artery end-diastolic flow.

METHODS

VEGF Expression was determined by immunohistochemical analysis of placentas from 17 pregnancies with normal infant birth weight and 17 pregnancies complicated by IUGR.

RESULTS

We found no significant differences in the expression of VEGF in villous syncytiotrophoblasts and intermediate trophoblasts in maternal decidua between IUGR and normal pregnancies. However, in both groups there was a strong correlation in the expression of VEGF with villous syncytiotrophoblasts and intermediate trophoblasts. In normal and IUGR pregnancies the infants' Apgar scores at birth were significantly correlated with VEGF staining in both syncytiotrophoblasts and intermediate trophoblasts (P < .05). A strong correlation also was found between cord hematocrit and VEGF staining in villous syncytiotrophoblasts (P < .05), but VEGF staining in intermediate trophoblasts was not correlated with cord hemoglobin or hematocrit.

CONCLUSIONS

Our results suggest that VEGF acts in an autocrine and paracrine fashion in both normal and IUGR placentas, and its expression can have an effect on the well being of the infant at birth.

Deletions within the azoospermia factor subregions of the Y chromosome in Hong Kong Chinese men with severe male-factor infertility: controlled clinical study

OBJECTIVE

To determine the patterns and the prevalence of microdeletions in the azoospermia factor subregions of the Y chromosome in Hong Kong Chinese men with severe male-factor infertility.

DESIGN

Controlled clinical study.

SETTING

Reproductive centre of a university teaching hospital, Hong Kong.

PARTICIPANTS

Fifty-eight men with severe male-factor infertility who participated in the in vitro fertilisation programme from May 1998 through March 1999, and 46 male volunteers with proven fertility.

MAIN OUTCOME MEASURES

Polymerase chain reaction analysis of DNA from peripheral blood lymphocytes using six loci spanning the AZFa, AZFb, and AZFc subregions of the Y chromosome. RESULTS. No microdeletions were detected in the fertile controls or in patients with obstructive azoospermia. Deletions within the AZFc subregion were found in 9% (4/44) of men with non-obstructive azoospermia or severe oligospermia. Neither AZFa nor AZFb deletions were detected in any participants.

CONCLUSION

Deletions within the azoospermia factor subregions of the Y chromosome are associated with severe male-factor infertility in Hong Kong Chinese men.

Cisplatin-induced emesis in the cat: effect of granisetron and dexamethasone

The emetic action of cisplatin was investigated in the cat using a closed circuit video recording system. In initial investigations, cisplatin 3 and 5 mg/kg, i.v. induced emesis over a 2-day period following a latency of 17.6+/-9.6 and 15.6+/-7.8 h, respectively. The anti-emetic efficacy of granisetron and dexamethasone was investigated in the cisplatin 5 mg/kg, i.v.-induced emesis model. In these experiments, cisplatin induced 47.0+/-14.0 and 20.0+/-9.0 retches+vomits on days 1 and 2, respectively, following a latency of 2.4+/-0.4 h. Granisetron (1 mg/kg, i.m.) administered three times per day reduced significantly the retching+vomiting response induced by cisplatin on days 1 and 2 by 100.0% (P<0.05) and 75.0% (P<0.05), respectively; dexamethasone (0.01-1 mg/kg, i.m.) administered three times per day reduced significantly the retching+vomiting response by 68.8-100.0% (P<0.05) and 33.3-100.0% (P<0.05) on days 1 and 2, respectively. The emetic action of cisplatin 7.5 mg/kg, i.v. was also investigated. This dose of cisplatin-induced emesis following a latency of 1.2+/-0.2 h and comprised 119.0+/-20.8 retches+vomits over a 24-h period. Granisetron and dexamethasone antagonized the emesis occurring in the first 3-h period (P<0.05) but were less effective to antagonize the subsequent emetic response (P0.05). The pharmacological sensitivity of low dose cisplatin-induced emesis in the cat is variable but unique and not representative of the clinical situation.

Cerebellar astrocytoma associated with von Hippel-Lindau disease: case report with molecular findings

We describe the rare occurrence of a cerebellar astrocytoma developing in a patient with the von Hippel-Lindau disease. This tumour possessed well-differentiated fibrillated astrocytes and moderate vascular proliferation. Tumour cells were uniformly GFAP positive and negative for lipids. This tumour showed an A to C mutation at nucleotide 675 at the splicing donor site of exon 2 of the VHL gene and a concurrent loss of heterozygosity of the 3p25 locus, a site of allelic deletions reported in some astrocytomas. Allelic loci at 17q11, a site of common loss in pilocytic astrocytoma, however, were retained in this tumour. This case illustrates that astrocytomas are rarely found in the von Hippel-Lindau disease and they may contain genetic changes common to both haemangioblastomas and some astrocytomas.

Analysis of cell cycle regulators: p16INK4A, pRb, and CDK4 in low- and high-grade meningiomas

Abnormalities in the p16INK4A, CDK4, and Rb genes, which regulate transition through G1 phase of the cell cycle, have been implicated in the progression of diverse types of cancer. To evaluate the involvement of p16INK4A, CDK4, and Rb in the tumorigenesis of meningiomas, the status of these genes or gene products were examined. The genetic alteration of the p16INK4A gene was examined by homozygous deletions and by mutation analysis. The methylation status of the p16INK4A was determined by Southern blotting. Neither homozygous deletions nor point mutations of the p16INK4A gene were observed in any of the 23 meningiomas. Partial rather than complete methylation of the p16INK4A gene at SacII or SmaI sites was shown in five (23.8%) meningiomas. The methylation status of the p16INK4A gene was not consistently associated with the expression of p16INK4A in meningiomas. These results suggest that the true relationship between methylation and expression of p16INK4A may be obscured in a complex manner by various mechanisms that regulate p16INK4A expression. Aberrant expressions of pRb and CDK4 were not observed in any of the meningiomas we examined, indicating that abnormalities of the pRb and CDK4 appear to be rare in meningiomas.

Loss of heterozygosity of chromosome 14q in low- and high-grade meningiomas

Abnormalities of chromosome 22q have been well studied as a major molecular genetic event in meningiomas. Chromosome 14q loss has also been shown to be a common phenomenon. However, only a few studies have reported molecular genetic changes of this chromosome in meningioma. In this study, we examined 41 sporadic meningiomas of different histological subtypes and grades with 15 polymorphic microsatellite markers covering a wide region on chromosome 14q. Overall, 37% (15 of 41) of cases showed loss of heterozygosity for one or more allelic markers. Thirty percent (10 of 33) of benign tumors showed allelic losses, whereas 62.5% (5 of 8) of high-grade meningiomas showed loss of heterozygosity. There were altogether eight cases of partial deletions and seven cases of probable monosomy of 14q. Allelic losses of 14q were also commonly seen in recurrent tumors (3 of 3, 100%), parasagittal tumors (4 of 7, 57%), and tumors with transitional subtype (7 of 14, 50%). Among the tumors with allelic losses of 14q, all except one concurrently showed loss of heterozygosity for markers on 22q by our previous study. Of the eight cases with partial deletions, one showed losses on 14q11.1-31, two showed deletions on 14q24.3-31, three showed losses at 14q32.1-32.2, and the remaining two showed deletions at 14q24.3-32.2. We therefore defined two cluster regions of deletion on chromosome 14q: 14q24.3-31 and 14q32.1-32.2. Our studies suggested that more than one tumor suppressor gene(s) residing on distinct regions of chromosome 14q are important in the development and atypical or anaplastic changes in meningiomas.