2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.

A genomic case study of mixed fibrolamellar hepatocellular carcinoma

We report the first comprehensive genomic analysis of a case of mixed conventional and fibrolamellar HCC (mFL-HCC). This study confirms the expression of DNAJB1:PRKACA, a fusion previously associated with pure FL-HCC but not conventional HCC, in mFL-HCC. These results indicate the DNAJB1:PRKACA fusion has diagnostic utility for both pure and mixed FL-HCC.

Background

Mixed fibrolamellar hepatocellular carcinoma (mFL-HCC) is a rare liver tumor defined by the presence of both pure FL-HCC and conventional HCC components, represents up to 25% of cases of FL-HCC, and has been associated with worse prognosis. Recent genomic characterization of pure FL-HCC identified a highly recurrent transcript fusion (DNAJB1:PRKACA) not found in conventional HCC.

Patients and Methods

We performed exome and transcriptome sequencing of a case of mFL-HCC. A novel BAC-capture approach was developed to identify a 400 kb deletion as the underlying genomic mechanism for a DNAJB1:PRKACA fusion in this case. A sensitive Nanostring Elements assay was used to screen for this transcript fusion in a second case of mFL-HCC, 112 additional HCC samples and 44 adjacent non-tumor liver samples.

Results

We report the first comprehensive genomic analysis of a case of mFL-HCC. No common HCC-associated mutations were identified. The very low mutation rate of this case, large number of mostly single-copy, long-range copy number variants, and high expression of ERBB2 were more consistent with previous reports of pure FL-HCC than conventional HCC. In particular, the DNAJB1:PRKACA fusion transcript specifically associated with pure FL-HCC was detected at very high expression levels. Subsequent analysis revealed the presence of this fusion in all primary and metastatic samples, including those with mixed or conventional HCC pathology. A second case of mFL-HCC confirmed our finding that the fusion was detectable in conventional components. An expanded screen identified a third case of fusion-positive HCC, which upon review, also had both conventional and fibrolamellar features. This screen confirmed the absence of the fusion in all conventional HCC and adjacent non-tumor liver samples.

Conclusion

These results indicate that mFL-HCC is similar to pure FL-HCC at the genomic level and the DNAJB1:PRKACA fusion can be used as a diagnostic tool for both pure and mFL-HCC.

Transient elastography for predicting clinical outcomes in patients with chronic liver disease

There is increasing interest in developing noninvasive means to evaluate liver fibrosis in patients with chronic liver disease to determine disease severity, prognosis and optimal treatment. Transient elastography (TE) has previously been demonstrated to predict the presence or absence of advanced fibrosis. The current study was conducted to determine whether TE can identify patients with chronic liver disease at risk of clinical decompensation. A total of 667 patients underwent TE and were followed for a median of 861 days and 57 patients achieved the primary outcome, a composite of clinical endpoints including death, ascites, encephalopathy, increased Child Score ≥ 2, variceal bleed, hepatocellular carcinoma or listing for transplant. Overall, TE had an area under the receiver operating characteristic curve of 0.87 for predicting clinical outcome. Using a cut-off of 10.5 kPa, TE has a sensitivity, specificity, positive predictive value and negative predictive value (NPV) of 94.7%, 63.0%, 19.3% and 99.2%, respectively. A predictive model for clinical events was developed using generalized cross-validation for clinical endpoints considering TE, liver biopsy results and multiple other predictors. Individually, TE performed better than biopsy, or any other variable, for predicting clinical outcome [Harrell's C Statistic 0.86 for TE, 0.78 for stage]. Patients with a TE score of >12.5 kPa were found to have a relative hazard for clinical event of 18.99 compared with patients with TE score <10.5. A combined variable model including TE, aspartate aminotransferase/alanine aminotransferase ratio and model for end-stage liver disease (MELD) yielded the highest predictive accuracy with Harrell's C value of 0.93. In the subset of patients with cirrhosis, TE was not found to be independently associated with clinical outcomes in univariate or multivariate analysis although it retained a high sensitivity and NPV of 97.5% and 92.3%, respectively, at a kPa cut-off of 10.5. TE can successfully identify patients with chronic liver disease who are at low risk of clinical decompensation over a time period of 2 years.

Hepatic colon cancer metastases in mice: dynamic in vivo correlation with hypoechoic rims visible at US

PURPOSE

To use videomicroscopy of tumor-bearing livers of live mice to depict tumors directly to determine the exact nature of rims seen on corresponding ultrasonographic (US) scans.

MATERIALS AND METHODS

Seventy-six hepatic colorectal cancer metastases were studied in exteriorized livers of 18 mice by using intravital microscopy, US, and histologic examination of the same tumors.

RESULTS

Hypoechoic rims correlated with distended sinusoidal spaces in vivo. These spaces surrounded only locally invasive tumors (mean diameter, 0.85 mm) that had obstructed the supplying terminal portal venules. These spaces, containing adherent leukocytes and tumor cells, gave rise to new tumor vasculature. Results of histologic examination of rims (portal inflammation, congested or compressed sinusoids, cell atrophy) correlated with leukocyte endothelial adherence, occluded sinusoids, and new vessel formation in vivo.

CONCLUSION

Unlike results from previous studies, dynamic in vivo observations of peritumoral rims demonstrated distended sinusoidal spaces giving rise to new tumor-penetrating vessels. These sinusoids arose around locally invasive tumors and were associated with more advanced intrahepatic disease. These dynamic observations provide a pathophysiologic explanation for previous histologic correlates of peritumoral rims.

Thrombus on indwelling central venous catheters: the histopathology of "Fibrin sheaths"

PURPOSE

Central venous catheters (CVC) may fail for many reasons, though "fibrin sheaths" blocking catheter ports are usually implicated. We examined the sheaths removed from dialysis catheters to determine their histopathology.

METHODS

Ten catheter strippings were performed and the removed material was studied grossly and microscopically.

RESULTS

The histologic specimens showed thrombus both with and without a proteinaceous sheath.

CONCLUSION

Dialysis catheters fail because of thrombus formation. This can occur in either the absence or presence of a protein coating on the catheter, the so-called "fibrin sheath."

Immunocytochemical staining of Kupffer and endothelial cells in fine needle aspiration cytology of hepatocellular carcinoma

OBJECTIVE

To evaluate the significance of the presence of Kupffer and endothelial cells in distinguishing hepatocellular carcinoma (HCC) and adenocarcinoma (AC) on cytologic smears.

STUDY DESIGN

Fine needle aspiration biopsies (FNABs) from 43 cases, 21 HCC and 22 AC (8 primary and 14 metastatic), were immunostained for Factor VIII and vimentin as markers for endothelial cells and Kupffer cells, respectively. Cytologic diagnosis was verified by histologic and/or clinical follow-up.

RESULTS

Eighteen of the 21 cases (86%) of HCC and 11 (5 primary and 6 metastatic) of 22 cases (50%) of AC showed positive immunostaining for Factor VIII (P = .02). Vimentin immunostaining was positive in 55% of HCCs and 41% of ACs (P = .74). Forty-five percent of cases of HCC showed immunostaining for both Factor VIII and vimentin, while 22% of cases of AC showed immunostaining for both Factor VIII and vimentin (P = .18).

CONCLUSION

Immunocytochemical identification of endothelial cells using Factor VIII may have important diagnostic value in separating HCC from adenocarcinomas in liver FNABs. The presence of Kupffer cells labeled with vimentin has no diagnostic significance in FNAB of these tumors.

Detection of concurrent/recurrent non-Hodgkin's lymphoma in effusions by PCR

A subset of patients with non-Hodgkin's lymphoma (NHL), present with or subsequently develop lymphocytic effusions. Differential diagnosis between reactive lymphocytosis and recurrent low-grade NHL is difficult by cytology alone. We studied the use of polymerase chain reaction (PCR)-based techniques to detect concurrent/recurrent NHL. Both primary tumors and atypical lymphocytic effusions of 12 low-grade B-NHL patients and 4 T-NHL patients were studied. Six pleural effusions (reactive/carcinomatous), in patients with no history of NHL, were included. Samples were amplified by PCR, using Fr3, Fr2, LJH, and VLJH primers specific for the immunoglobulin heavy chain (IgH) gene and Vgamma-8, Vgamma9, Vgamma10, Vgamma11 and Jgamma1/Jgamma2 consensus primers specific for the T-cell receptor gamma (TCR-gamma) gene. IgH gene PCR products were analyzed by polyacrylamide gel electrophoresis (PAGE). TCR-gamma gene PCR products were analyzed using a novel nonradioactive single-strand conformational polymorphism (SSCP) procedure. IgH gene rearrangement analysis demonstrated monoclonality in 11/12 primary low-grade B-NHLs. Identical monoclonal bands were found in both primary tumor and effusion in 9 patients. TCR-gamma gene rearrangement analysis demonstrated monoclonality in 4 of 4 primary T-NHLs. Identical monoclonal banded patterns were found in both primary tumor and effusion in 3 patients. Our results strongly support the diagnosis of concurrent/recurrent NHL in 13 of 16 (81%) cases of atypical lymphocytic effusions. IgH/PAGE and TCR-gamma/SSCP analyses are useful tools in the diagnoses of lymphocytic effusions in patients with NHL.

Several noncontiguous domains of CDK4 are involved in binding to the P16 tumor suppressor protein

Cyclin-dependent kinase 4 (CDK4) is a key molecule in the regulation of cell cycle progression at the G1-S phase restriction point. Its activity is specifically regulated by p16 (also known as p16/CDKN2A, p16(INK4a), and MTS1), a tumor suppressor frequently altered in human cancers. A specific mutation in CDK4 codon 24 (Arginine to Cysteine) prevents p16 binding and thus inhibition by p16. This mutated CDK4 acts as a dominant oncogene and has been found in both sporadic and familial melanoma. To study the effects of other mutations in CDK4, we generated a panel of 18 CDK4 mutants using Charged-to-Alanine scanning mutagenesis, and investigated the p16-binding capacity of these mutants to identify novel sites involved in p16 binding. The mutant CDK4 proteins were generated by direct coupled transcription-translation in vitro and tested for binding to p16 using a p16-GST fusion protein. Several mutants demonstrated loss of p16 binding. In addition to the previously identified codon 24 mutants, alterations in and around codon 22, 25, 97, and 281 all showed loss of p16 binding capacity. These results indicate that several noncontiguous amino acid sequences on CDK4 are required for binding to p16, which suggests the existence of multiple sites of interaction with p16. Since p16-binding deficient CDK4 has oncogenic potential, these mutations may be present in melanomas or other human neoplasms.

Malignancy-related hydrocephalus: clinical features and results of ventricular peritoneal shunt procedure in three patients

Three patients with hydrocephalus secondary to central nervous system (CNS) metastases from lung or breast cancer are reviewed representing less than 5% of patients with CNS metastases seen at The Cancer Center of Boston over a 10-year period. The clinical picture is characterized by ataxia and mental confusion with dilated ventriculi on computed tomography (CT) scan of the brain. Computerized tomography of the brain and microscopic analysis of the cerebrospinal fluid are complementary in establishing the diagnosis of meningeal carcinomatosis. Surgical management by ventricular peritoneal shunt is an important component to multimodality therapy. The clinical course and extended survival in three patients provides a basis for recommending palliative surgical bypass as a therapeutic intervention with or without intrathecal chemotherapy, radiation, or both.

Increased spasticity in a chronic spinal cord injury patient after scabies infestation: a case report

Spasticity is a common feature of spinal cord injury (SCI). Spasticity exacerbation is commonly encountered with nociceptive and exteroceptive stimuli including bladder and bowel dysfunction, pressure sores, contracture, tight-fitting leg bags and clothing, and ingrown toenail. This report describes a patient with chronic SCI (T4 level) who complained of increasing spasticity of bilateral lower extremities for 5 weeks. He also had skin lesions on different parts of his body, accompanied by itching above the spinal cord lesion level. A clinical diagnosis of scabies was made and pharmacologic treatment was initiated. Following treatment, spasticity was significantly reduced and the skin rash with itching faded out. This report is the first of scabies skin infestation lesions triggering exacerbation of spasticity in an SCI patient.

Liver metastases from colorectal cancer: drug delivery with liposome-encapsulated doxorubicin

PURPOSE

To evaluate the intratumoral distribution of liposome-encapsulated doxorubicin.

MATERIALS AND METHODS

Tumor-bearing livers of 24 mice were studied with in vivo fluorescence and electron microscopy after injection of liposomal doxorubicin in the hepatic artery, portal vein, or tail vein. Distribution and uptake of liposomes and doxorubicin in tumors were compared at 5, 30, and 60 minutes after injection. In vitro evaluation of uptake of doxorubicin in Kupffer cells and in human colorectal cancer cells incubated under normoxic and hypoxic conditions for 5, 30, and 60 minutes was performed with fluorescence microscopy.

RESULTS

Doxorubicin autofluorescence was seen in tumors 30 minutes after intraarterial and intraportal injection and was statistically significantly greater at 60 minutes (P < .001). Liposomes were observed in small tumors (diameter < 300 microns) and were trapped in Kupffer cells around larger, hypovascular tumors. Electron microscopy findings confirmed intracytoplasmic, perinuclear uptake of liposomes in tumor cells. In vitro, a higher proportion of doxorubicin was seen in cancer cells (92%) than in Kupffer cells (75%) after 60 minutes incubation.

CONCLUSION

Liposomal doxorubicin can be reliably delivered to liver metastases via the hepatic artery, eliminating need for tumor embolization. Further evaluation is warranted, and the drug may be useful for treating patients with unresectable liver metastases.

Pulmonary hemorrhage. An uncommon cause of pulmonary infiltrates in patients with AIDS

We describe two patients with AIDS who developed new diffuse pulmonary infiltrates during the course of their hospitalization. In both cases, the infiltrates were attributed to pulmonary hemorrhage complicating an existing condition rather than representing a new pulmonary process. Identification of pulmonary hemorrhage in these patients allowed for discontinuation of treatment with empiric medications and continued appropriate supportive care.

Terminal duct carcinoma. Recognition of a low-grade salivary adenocarcinoma

We describe six cases of terminal duct carcinoma of the minor salivary glands. All were localized to the oral cavity, without regional nodal or distant metastases. Histologically, five were originally mistaken for adenoid cystic carcinoma; one was interpreted as monomorphic adenoma with areas of adenoid cystic carcinoma. Treatment consisted of wide resection with or without radiation therapy, with no incidence of recurrence or metastasis. The characteristics of this recently described pathologic entity are reviewed. The less aggressive behavior of this tumor compared with adenoid cystic carcinoma should call for less radical therapy, with a favorable prognosis in most cases. Recognition of this tumor as a distinct clinical and pathologic entity is therefore important.

Pedal leiomyoma

Pedal leiomyoma has rarely been reported in the literature. The tumor has a predilection for middle-aged females, is often associated with pain, and usually lies subcutaneously within a well-defined capsule. The authors present the largest pedal leiomyoma in the English literature.