Non-papillary thyroid carcinoma diagnoses in The Bethesda System for Reporting Thyroid Cytopathology categories V and VI: An institutional experience

BACKGROUND

The non-papillary thyroid carcinoma (PTC) subgroups of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) categories V (Suspicious for malignancy) and VI (Malignant) are rare, and specific tumor typing is difficult. We aimed to analyze histologic outcomes and to investigate the points of caution.

METHODS

We reviewed the electronic database and identified 12,215 cases of thyroid fine-needle aspiration cytology between 2013 and 2022. In total, 2783 patients were diagnosed with TBSRTC V or VI. Of these, 51 patients with non-PTC diagnosis were identified. Histological outcomes were analyzed with the cytologic findings.

RESULTS

The subgroups of non-PTC diagnoses in TBSRTC category V or VI consisted of medullary thyroid carcinoma (MTC) (13/51, 25.5 %), anaplastic thyroid carcinoma (3/51, 5.9 %), lymphoma (2/51, 3.9 %), metastatic tumor (4/51, 7.8 %), and malignant, not otherwise specified (NOS) (29/51, 56.9 %). The concordance rate of the histological outcomes was 30 % (12/40), predominantly comprising MTC cases. The obscuring factors for specific tumor typing in the suspicious for malignancy/malignant NOS cytology diagnosis group was mixed pattern of well differentiated thyroid carcinoma and less differentiated carcinoma cells (9/24, 37.5 %), low cellularity (7/24, 29.2 %) and a history of non-thyroid organ malignancy (6/24, 25 %). The less differentiated carcinoma component in mixed pattern consisted of 2 poorly differentiated thyroid carcinomas, 2 anaplastic thyroid carcinomas, 4 high-grade PTCs and 1 high-grade MTC.

CONCLUSION

The high-grade feature of PTC or MTC cytology is a noteworthy obscuring factor in specific tumor typing of non-PTC cytology diagnosis.

Characterization of the genomic alterations in poorly differentiated thyroid cancer

Poorly differentiated thyroid carcinoma (PDTC) is a subtype of thyroid cancer that has a high rate of metastasis or recurrence and a relatively poor prognosis. However, there are few studies that have been conducted on PDTC at the whole protein-coding gene scale. Here, we performed genomic profiling of 15 patients with PDTC originated from follicular thyroid carcinoma using whole exome sequencing and also performed gene functional enrichment analysis of differentially expressed genes (DEGs) for three patients. Further, we investigated genetic variants associated with PDTC progression and the characteristics of clinical pathology. We revealed somatic genomic alterations in the RAF1, MAP2K2, and AKT2 genes that were not reported in previous studies. We confirmed frequent occurrences in the RAS gene in patients with PDTC; the genetic alterations were associated with the RAS-RAF-MEK-ERK/JNK, PI3K-AKT-mTOR signaling pathways, and the cell cycle. DEG analysis showed that immune response was lower in cancer tissues than in normal tissues. Through the association analysis of somatic mutations and the characteristics of clinical pathology from patients with PDTC, the somatic mutations of ABCA12, CLIP1, and ATP13A3 were significantly associated with a vascular invasion phenotype. By providing molecular genetic insight on PDTC, this study may contribute to the discovery of novel therapeutic target candidates.

Deep learning-based image enhancement in optical coherence tomography by exploiting interference fringe

Optical coherence tomography (OCT), an interferometric imaging technique, provides non-invasive, high-speed, high-sensitive volumetric biological imaging in vivo. However, systemic features inherent in the basic operating principle of OCT limit its imaging performance such as spatial resolution and signal-to-noise ratio. Here, we propose a deep learning-based OCT image enhancement framework that exploits raw interference fringes to achieve further enhancement from currently obtainable optimized images. The proposed framework for enhancing spatial resolution and reducing speckle noise in OCT images consists of two separate models: an A-scan-based network (NetA) and a B-scan-based network (NetB). NetA utilizes spectrograms obtained via short-time Fourier transform of raw interference fringes to enhance axial resolution of A-scans. NetB was introduced to enhance lateral resolution and reduce speckle noise in B-scan images. The individually trained networks were applied sequentially. We demonstrate the versatility and capability of the proposed framework by visually and quantitatively validating its robust performance. Comparative studies suggest that deep learning utilizing interference fringes can outperform the existing methods. Furthermore, we demonstrate the advantages of the proposed method by comparing our outcomes with multi-B-scan averaged images and contrast-adjusted images. We expect that the proposed framework will be a versatile technology that can improve functionality of OCT.

TROP-2 and 5hmC expression in follicular-patterned thyroid neoplasm emphasizing tiny well-formed papillae

BACKGROUND

Follicular-patterned thyroid neoplasms (FPTNs), characterized by predominantly follicular growth pattern, represent diverse pathological entities. We aimed to study the nuclear features and the immunoexpression of trophoblast cell-surface antigen 2 (TROP-2) and 5-hydroxymethylcytosine (5hmC) in FPTNs.

DESIGN

FPTNs were divided into 4 groups: I) noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), II) encapsulated follicular variant of papillary thyroid carcinoma (FVPTC) with capsular invasion, III) infiltrative FVPTC, and IV) PTC with a predominantly follicular pattern and well-formed papillae (<1%). Nuclear characteristics were evaluated by image analysis. TROP-2 and 5hmC immunostains were analyzed correlating with histological features using QuPath.

RESULTS

From the group I to II, III, and IV, there is a gradual increase in nuclear atypia in terms of the nuclear area, max caliper, perimeter, circularity, and hematoxylin OD means (corresponding to nuclear enlargement, membrane irregularity, and clearing). A similar trend is observed in the TROP-2 expression. 5hmC expression is highly preserved in groups I, II, and III in contrast to a significant loss in group IV. Group IV tumors show more frequent regional lymph node involvement and the highest BRAF V600E mutation rate.

CONCLUSION

Among FPTNs, group IV tumors exhibit the most advanced nuclear atypia, highest TROP-2 expression, significant 5HMC expression loss, frequent regional lymph node involvement, and the highest BRAF V600E mutation rate. Our data further support that the presence of any true papillae should be an exclusion criterion for NIFTP. Therefore, well-formed papillae even if very minute (<1% of the tumor) should not be overlooked.

A case of nontuberculous mycobacteria-associated thyroiditis mimicking subacute thyroiditis

We describe a case of nontuberculous mycobacteria infection in the thyroid gland in a 54-year-old woman who had painful thyroid enlargement. Ultrasonography showed ill-defined hypoechoic lesions without increased vascularity in both upper lobes of the thyroid gland. Fine needle aspiration biopsy was performed, and pathology showed granulomatous inflammation with necrotic debris that the pathologist suspected was subacute granulomatous thyroiditis or tuberculosis of the thyroid gland. Nontuberculous mycobacteria infection was confirmed after right hemithyroidectomy. Antimycobacterial therapy was initiated as the treatment of choice. Nontuberculous mycobacteria in the thyroid gland appear to be rare. In clinical practice, however, it should be considered as a differential diagnosis of a painful thyroid mass. For accurate diagnosis, clinical and radiological features plus histological examination are required.

Diagnostic Utility of INSM1 in Medullary Thyroid Carcinoma

Insulinoma-associated protein 1 (INSM1) is shown to be an excellent marker for neuroendocrine differentiation. However, the diagnostic utility of INSM1 in medullary thyroid carcinoma (MTC) has not yet been extensively investigated. INSM1 staining was performed on 21 MTCs, 7 MTC mimickers (including 3 papillary carcinomas, 2 poorly differentiated carcinomas, 1 follicular adenoma, and 1 nodular plasma cell hyperplasia), and 3 cases of C-cell hyperplasia. INSM1 staining of these cases was compared with the traditional MTC markers including calcitonin (CT), monoclonal carcinoembryonic antigen (mCEA), chromogranin A (CgA), and synaptophysin (Syn). The H-score was generated using the QuPath program, an open-source image analysis software. All 21 MTC cases and 3 C-cell hyperplasia cases were positive for all markers. The MTC mimickers were entirely negative for INSM1. INSM1 and Syn displayed, more consistently, high expression with minimal variability than CgA that showed a wide range of expression with significant variability. mCEA and CT exhibited mostly a high expression with some variability. Being a nuclear stain, interpretation was easier with INSM1 compared to other cytoplasmic markers. INSM1 is an excellent marker for neuroendocrine differentiation, entirely applicable in the diagnosis of MTC and C-cell hyperplasia with high sensitivity and specificity. In comparison with the traditional MTC markers, INSM1 is unique in the crisp nuclear staining pattern with a consistent, diffuse, and strong expression. INSM1 can be potentially combined with CT or mCEA as a dual stain, especially when the lesional tissue is limited for a panel of immunostains.

TROP-2, 5hmC, and IDH1 Expression in Anaplastic Thyroid Carcinoma

BACKGROUND

Anaplastic thyroid carcinoma (ATC), a highly aggressive malignancy, has no effective treatment to date. Trophoblast cell-surface antigen 2 (TROP-2), a transmembrane glycoprotein, has been suggested to be a promising novel target for sacituzumab govitecan, an antibody-drug conjugate. 5-Hydroxymethylcytosine (5hmC) has a role in tumor suppression and promoting modification. Additionally, isocitrate dehydrogenase 1 (IDH1) mutations are strongly associated with increased overall survival in gliomas and worse prognosis in leukemias. This study attempts to evaluate the immunoexpression of TROP-2, 5hmC, and IDH1 in ATCs and to determine their potential impact in targeted therapy.

METHODS

Twenty-four ATCs were retrieved, with 9 cases that occurred de novo and 15 cases derived from either papillary thyroid carcinoma (PTC) or follicular thyroid carcinoma (FTC). Sections were immunostained with TROP-2, 5hmC, and IDH1 antibodies, and evaluated using the QuPath program. The t tests were performed using SPSS software.

RESULTS

TROP-2 was detected in 12 ATCs with 9 cases demonstrating a high expression and in all PTC components, and absent in all FTC components of secondary ATCs. 5hmC expression was moderately reduced in PTC and FTC components and markedly reduced in ATC. The entire cohort showed a total absence of IDH1.

CONCLUSIONS

Increased TROP-2 immunoexpression in some ATCs supports that these patients may potentially benefit from an antibody-drug conjugate therapy targeting TROP-2. Markedly reduced 5hmC expression suggests that 5hmC may be used as potential therapeutic targets for ATC. The total lack of IDH1 R132H mutation by immunostain indicates that it has no prognostic and therapeutic value in ATC.

Contribution of cytologic examination to diagnosis of poorly differentiated thyroid carcinoma

Background

The cytologic diagnosis of poorly differentiated thyroid carcinoma (PDTC) is difficult because it lacks salient cytologic findings and shares cytologic features with more commonly encountered neoplasms. Due to diverse cytologic findings and paucicellularity of PDTC, standardization of cytologic diagnostic criteria is limited. The purpose of this study is to investigate and recognize diverse thyroid findings of fine needle aspiration (FNA) cytology and frozen smear cytology in diagnosis of this rare but aggressive carcinoma.

Methods

The present study included six cases of FNA cytology and frozen smears of histologically diagnosed PDTCs.

Results

PDTC showed cytologic overlap with well-differentiated thyroid carcinomas (WDTCs). Five of six cases showed dedifferentiation arising from well differentiated thyroid carcinomas. Only one de novo PDTC showed highly cellular smears composed of discohesive small cells, high nuclear/cytoplasmic (N/C) ratio, prominent micronucleoli, and irregular nuclei. Retrospectively reviewed, these findings are highly suspicious for PDTC. Cytologic findings of nuclear atypia, pleomorphism, and irregularity were frequently found, whereas scattered small cells were seen only in the de novo case.

Conclusions

Heterogeneous cytologic findings of PDTCs are shared with those of WDTCs and contribute to difficult preoperative cytologic diagnoses. Most PDTCs show dedifferentiation from WDTCs. Albeit rare, de novo PDTC should be considered with cytology showing discohesive small cells with high N/C ratio. This will enable precise diagnosis and prompt treatment of this aggressive malignancy

Comparison of papanicolaou smear and human papillomavirus (HPV) test as cervical screening tools: can we rely on HPV test alone as a screening method? An 11-year retrospective experience at a single institution

Background

The decrease in incidence of cervical dysplasia and carcinoma has not been as dramatic as expected with the development of improved research tools and test methods. The human papillomavirus (HPV) test alone has been suggested for screening in some countries. The National Cancer Screening Project in Korea has applied Papanicolaou smears (Pap smears) as the screening method for cervical dysplasia and carcinoma. We evaluated the value of Pap smear and HPV testing as diagnostic screening tools in a single institution.

Methods

Patients co-tested with HPV test and Pap smear simultaneously or within one month of each other were included in this study. Patients with only punch biopsy results were excluded because of sampling errors. A total of 999 cases were included, and the collected reports encompassed results of smear cytology, HPV subtypes, and histologic examinations.

Results

Sensitivity and specificity of detecting high-grade squamous intraepithelial lesion (HSIL) and squamous cell carcinoma (SCC) were higher for Pap smears than for HPV tests (sensitivity, 97.14%; specificity, 85.58% for Pap smears; sensitivity, 88.32%; specificity, 54.92% for HPV tests). HPV tests and Pap smears did not differ greatly in detection of low-grade squamous intraepithelial lesion (85.35% for HPV test, 80.31% for Pap smears). When atypical glandular cells were noted on Pap smears, the likelihood for histologic diagnosis of adenocarcinoma following Pap smear was higher than that of high-risk HPV test results (18.8 and 1.53, respectively).

Conclusions

Pap smears were more useful than HPV tests in the diagnosis of HSIL, SCC, and glandular lesions.

A Multi-institutional Study of Prevalence and Clinicopathologic Features of Non-invasive Follicular Thyroid Neoplasm with Papillary-like Nuclear Features (NIFTP) in Korea

Background

In the present multi-institutional study, the prevalence and clinicopathologic characteristics of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) were evaluated among Korean patients who underwent thyroidectomy for papillary thyroid carcinoma (PTC).

Methods

Data from 18,819 patients with PTC from eight university hospitals between January 2012 and February 2018 were retrospectively evaluated. Pathology reports of all PTCs and slides of potential NIFTP cases were reviewed. The strict criterion of no papillae was applied for the diagnosis of NIFTP. Due to assumptions regarding misclassification of NIFTP as non-PTC tumors, the lower boundary of NIFTP prevalence among PTCs was estimated. Mutational analysis for BRAF and three RAS isoforms was performed in 27 randomly selected NIFTP cases.

Results

The prevalence of NIFTP was 1.3% (238/18,819) of all PTCs when the same histologic criteria were applied for NIFTP regardless of the tumor size but decreased to 0.8% (152/18,819) when tumors ≥1 cm in size were included. The mean follow-up was 37.7 months and no patient with NIFTP had evidence of lymph node metastasis, distant metastasis, or disease recurrence during the follow-up period. A difference in prevalence of NIFTP before and after NIFTP introduction was not observed. BRAF^V600E mutation was not found in NIFTP. The mutation rate for the three RAS genes was 55.6% (15/27).

Conclusions

The low prevalence and indolent clinical outcome of NIFTP in Korea was confirmed using the largest number of cases to date. The introduction of NIFTP may have a small overall impact in Korean practice.

Primary Necrobiotic Xanthogranulomatous Sialadenitis with Submandibular Gland Localization without Skin Involvement

Necrobiotic xanthogranulomatous reaction is a multiorgan, non-Langerhans cell histiocytosis with an unknown etiology. Occurrence in the salivary gland is extremely rare. We recently identified a case of necrobiotic xanthogranulomatous sialadenitis in a 73-year-old Korean woman who presented with a painless palpable lesion in the chin. There was no accompanying cutaneous lesion. Partial resection and subsequent wide excision with neck dissection were performed. Pathological examination showed a severe inflammatory lesion that included foamy macrophages centrally admixed with neutrophils, eosinophils, lymphocytes, plasma cells, and scattered giant cells, as well as necrobiosis. During the 12-month postoperative period, no grossly remarkable change in size was noted. Necrobiotic xanthogranulomatous inflammation may be preceded by or combined with hematologic malignancy. Although rare, clinicians and radiologists should be aware that an adhesive necrobiotic xanthogranuloma in the salivary gland may present with a mass-like lesion. Further evaluation for hematologic disease and close follow-up are needed when a pathologic diagnosis is made.

Intraoperative Frozen Cytology of Central Nervous System Neoplasms: An Ancillary Tool for Frozen Diagnosis

BACKGROUND

Pathologic diagnosis of central nervous system (CNS) neoplasms is made by comparing light microscopic, immunohistochemical, and molecular cytogenetic findings with clinicoradiologic observations. Intraoperative frozen cytology smears can improve the diagnostic accuracy for CNS neoplasms. Here, we evaluate the diagnostic value of cytology in frozen diagnoses of CNS neoplasms.

METHODS

Cases were selected from patients undergoing both frozen cytology and frozen sections. Diagnostic accuracy was evaluated.

RESULTS

Four hundred and fifty-four cases were included in this retrospective single-center review study covering a span of 10 years. Five discrepant cases (1.1%) were found after excluding 53 deferred cases (31 cases of tentative diagnosis, 22 cases of inadequate frozen sampling). A total of 346 cases of complete concordance and 50 cases of partial concordance were classified as not discordant cases in the present study. Diagnostic accuracy of intraoperative frozen diagnosis was 87.2%, and the accuracy was 98.8% after excluding deferred cases. Discrepancies between frozen and permanent diagnoses (n = 5, 1.1%) were found in cases of nonrepresentative sampling (n = 2) and misinterpretation (n = 3). High concordance was observed more frequently in meningeal tumors (97/98, 99%), metastatic brain tumors (51/52, 98.1%), pituitary adenomas (86/89, 96.6%), schwannomas (45/47, 95.8%), high-grade astrocytic tumors (47/58, 81%), low grade astrocytic tumors (10/13, 76.9%), non-neoplastic lesions (23/36, 63.9%), in decreasing frequency.

CONCLUSIONS

Using intraoperative cytology and frozen sections of CNS tumors is a highly accurate diagnostic ancillary method, providing subtyping of CNS neoplasms, especially in frequently encountered entities.

Optimal combination of treatment modality to increase survival in patients with anaplastic thyroid carcinoma: A STROBE compliant retrospective study

There is little consensus on the optimal treatment approach for newly diagnosed patients. The present study aims to provide additional evidence by evaluating a series of patients diagnosed with anaplastic thyroid carcinoma (ATC) and analyzing factors related to increased survival. This was a retrospective cohort report structured according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guideline. Demographics, chief complaint, history of prior thyroid cancer, stage at presentation, management modalities (surgery, chemotherapy, radiotherapy, or observation), completeness or resection, and survival period since initial diagnosis were reviewed for patients with documentation of histologic ATC diagnosis between 2003 and 2016. The median survival period for 34 patients (11 males, 23 females) was 93.5 days. Patients aged 70 or younger (111 days) tended to survive longer than those older 70 (88 days) (P = .081). Observation, surgery only, radiotherapy only, and chemo-radiotherapy after surgery group showed median survival of 88 days, 49 days (range 14-528), 61.5 days, and 225 days, respectively. There was also no significant difference in survival between the 10 (29.4%) stage IVb (225 days) and 23 (67.7%) IVc (88 days) patients (P = .242). The median survival of the R1 resection group was 514 days while that of the R2 group was 102 days (P = .338). There were no significant difference between patients with the de novo ATC (112 days) and patients with papillary thyroid carcinoma origin ATC (99 days) (P = .297). Results from our series of 34 patients with ATC show that more intense combination of surgery and chemo-radiotherapy tends to secure a longer survival period. Therefore we recommend a multi-modality approach after a comprehensive consultation with the patient.

Nuclear features of papillary thyroid carcinoma: Comparison of Core needle biopsy and thyroidectomy specimens

BACKGROUND

Core needle biopsy (CNB) has been used as an alternative or a complementary method for diagnosis of thyroid nodules. However, morphological analysis of the nuclear features of papillary thyroid carcinoma (PTC) cells obtained via CNB remains unclear. Hence, we examined the differences between the PTC nuclear features in CNB and thyroidectomy specimens.

METHODS

Ten PTC patients, who underwent both CNB and thyroidectomy, were selected. Microscopic photographs of three representative areas of the PTC and adjacent parenchyma were taken. Ten cells per photograph were chosen, and 1200 cells were evaluated (300 PTC and 300 follicular cells in the CNB and thyroidectomy specimens, respectively). The area, circumference, major axis, and minor axis were measured using an image analyzer. Detailed nuclear features (size and shape, membrane irregularity, chromatin characteristics) were scored using a 3-point scale.

RESULTS

The mean nuclear area, circumference, major axis, and minor axis of PTC cells in the CNB specimen were 1.76, 1.34, 1.34, and 1.29 times larger than those of the follicular cells (p<0.001); similar results were seen in the thyroidectomy specimens (2.04, 1.41, 1.37, and 1.37: p<0.001). Comparative analysis revealed that these parameters were significantly smaller in the CNB specimens than those in the thyroidectomy specimens (p<0.001). Nuclear grades were also lower in the former owing to poor chromatin characteristics (clearing and margination) (p<0.01).

CONCLUSION

Considering that the PTC nuclei in CNB specimens are smaller with fewer irregularities and less clear than those in thyroidectomy specimens, we need to emphasize caution when using CNB specimens for diagnosis.

Transcriptomic and histopathological analysis of cholangiolocellular differentiation trait in intrahepatic cholangiocarcinoma

BACKGROUND & AIMS

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous entity with diverse aetiologies, morphologies and clinical outcomes. Recently, histopathological distinction of cholangiolocellular differentiation (CD) of iCCA has been suggested. However, its genome-wide molecular features and clinical significance remain unclear.

METHODS

Based on CD status, we stratified iCCAs into iCCA with CD (n=20) and iCCA without CD (n=102), and performed an integrative analysis using transcriptomic and clinicopathological profiles.

RESULTS

iCCA with CD revealed less aggressive histopathological features compared to iCCA without CD, and iCCA with CD showed favourable clinical outcomes of overall survival and time to recurrence than iCCA without CD (P<.05 for all). Transcriptomic profiling revealed that iCCA with CD resembled an inflammation-related subtype, while iCCA without CD resembled a proliferation subtype. In addition, we identified a CD signature that can predict prognostic outcomes of iCCA (CD_UP, n=486 and CD_DOWN, n=308). iCCAs were subgrouped into G1 (positivity for CRP and CDH2, 7%), G3 (positivity for S100P and TFF1, 32%) and G2 (the others, 61%). Prognostic outcomes for overall survival (P=.001) and time to recurrence (P=.017) were the most favourable in G1-iCCAs, intermediate in G2-iCCAs and the worst in G3-iCCAs. Similar result was confirmed in the iCCA set from GSE26566 (n=68).

CONCLUSIONS

CD signature was identified to predict the prognosis of iCCA. The combined evaluation of histology of CD and protein expression status of CRP, CDH2, TFF1 and S100P might help subtyping and predicting clinical outcomes of iCCA.

Thyroid Fine-Needle Aspiration Cytology Practice in Korea

We reviewed the current status of thyroid fine-needle aspiration cytology (FNAC) in Korea. Thyroid aspiration biopsy was first introduced in Korea in 1977. Currently, radiologists aspirate the thyroid nodule under the guidance of ultrasonography, and cytologic interpretation is only legally approved when a cytopathologist makes the diagnosis. In 2008, eight thyroid-related societies came together to form the Korean Thyroid Association. The Korean Society for Cytopathology and the endocrine pathology study group of the Korean Society for Pathologists have been updating the cytologic diagnostic guidelines. The Bethesda System for Reporting Thyroid Cytopathology was first introduced in 2009, and has been used by up to 94% of institutions by 2016. The average diagnosis rates are as follows for each category: I (12.4%), II (57.9%), III (10.4%), IV (2.9%), V (3.7%), and VI (12.7%). The malignancy rates in surgical cases are as follows for each category: I (28.7%), II (27.8%), III (50.6%), IV (52.3%), V (90.7%), and VI (100.0%). Liquid-based cytology has been used since 2010, and it was utilized by 68% of institutions in 2016. The categorization of thyroid lesions into "atypia of undetermined significance" or "follicular lesion of undetermined significance" is necessary to draw consensus in our society. Immunocytochemistry for galectin-3 and BRAF is used. Additionally, a molecular test for BRAF in thyroid FNACs is actively used. Core biopsies were performed in only 44% of institutions. Even the institutions that perform core biopsies only perform them for less than 3% of all FNACs. However, only 5% of institutions performed core biopsies up to three times more than FNAC.

Pediatric intracerebral histiocytic sarcoma with rhabdoid features: Case report and literature review

A 16-year-old boy presented with marked weight loss, weakness of the left extremities and dizziness of 2 months duration and vomiting for 2 days. Brain MRI showed an approximately 6.5 × 5.3 cm-sized huge heterogeneous enhancing mass located in the corpus callosum, extending into the lateral ventricle. Open biopsy showed that the lesion consisted of lymphoplasmacytes and plump histiocytes with rhabdoid morphology, which were stained with S-100 protein, CD68 (KP1) and negative for CD1a. Histiocytic tumor was initially diagnosed. Chemotherapy using methotrexate, 6-mercaptopurine, vinblastine, interferon-alpha and dexamethasone was performed. After 5 months, partial removal was done. Microscopically, plump and bizarre tumor cells as well as rhabdoid features were found. Occasional spindle cells and necrosis were also found. These cells were positive for CD163, CD68, lysozyme, CD4, INI-1 and BRG1. BRAF V600E mutation was detected. The lesion was finally diagnosed as histiocytic sarcoma. Radiotherapy (6000 cGy in 30 fractions) was done. Both cerebral and extracerebral histiocytic sarcomas have long been diagnosed by unclarified criteria; its rarity as well as previously unclarified criteria can easily lead to a misinterpretation. Histiocytic sarcoma of the CNS is exceptionally rare in children, associated with an exceptionally poor prognosis. To date, only seven cases of pediatric cerebral histiocytic sarcomas have been reported. The present case is the first pediatric case showing BRAF V600E-mutated intracerebral histiocytic sarcoma.

Morphologic Analysis of Cytomegalovirus Infected Cells in Bronchial Washing Cytology: Comparison of Liquid-Based Preparation and Conventional Smear

Background:

The cytopathic effects of cytomegalovirus (CMV) infection have been well described since the virus was first reported; however, the morphology of CMV infection has not been clearly studied. We examined the difference in detailed cytologic findings in bronchial washing cytology between liquid-based and conventionally prepared smears.

Methods:

Bronchial washing cytology was processed using either the conventional preparation (CP) or liquid-based preparation (LBP). Sixty-nine cells with typical cytopathic effects of CMV infection were detected on CP slides and 18 cells on LBP slides. Using the image analyzer, area, circumference, major axis, and minor axis of the cytoplasm, nucleus, and intranuclear inclusion were measured in singly scattered CMV-infected cells, and histiocytes were used as a control.

Results:

The mean cytoplasmic area of CMV-infected cells was 1.47 times larger than that of histiocytes in CP and 2.92 times larger in LBP (p<.05). The mean nuclear area of CMV-infected cells was 2.61 times larger than that of histiocytes in CP and 4.25 times larger in LBP (p<.05). The nucleus to cytoplasm ratio and intranuclear inclusion to cytoplasm ratio of the mean area, circumference, major axis, and minor axis in CP were larger than those in LBP (p<.05).

Conclusions:

The sizes of cytoplasm, nucleus, and intranuclear inclusion were larger in LBP than in CP, indicating that CMV-infected cells are easily detectable in LBP. However, the nucleus-to-cytoplasm ratio was larger in CP, suggesting that differentiation from malignancy or regenerative atypia requires caution in CP.

Rare Case of Anal Canal Signet Ring Cell Carcinoma Associated with Perianal and Vulvar Pagetoid Spread

A 61-year-old woman was referred to surgery for incidentally found colonic polyps during a health examination. Physical examination revealed widespread eczematous skin lesion without pruritus in the perianal and vulvar area. Abdominopelvic computed tomography showed an approximately 4-cm-sized, soft tissue lesion in the right perianal area. Inguinal lymph node dissection and Mils’ operation extended to perianal and perivulvar skin was performed. Histologically, the anal canal lesion was composed of mucin-containing signet ring cells, which were similar to those found in Pagetoid skin lesions. It was diagnosed as an anal canal signet ring cell carcinoma (SRCC) with perianal and vulvar Pagetoid spread and bilateral inguinal lymph node metastasis. Anal canal SRCC is rare, and the current case is the third reported case in the English literature. Seven additional cases were retrieved from the world literature. Here, we describe this rare case of anal canal SRCC with perianal Pagetoid spread and provide a literature review.

Genomic profiling of patient-derived colon cancer xenograft models

Recent evidence suggests that patient derived xenograft (PDX) models can maintain certain pathological and molecular features of the original disease. However, these characterizations are limited to immunohistochemistry or by tissue microarray analysis. We conducted a high-throughput sequencing of primary colon tumor and PDX has not been reported yet. Fresh primary colon cancer tissues that originate from surgery were implanted into the subcutaneous space of 6- to 8-week-old female BALB/c nu/nu or NOD/SCID mice and serially passaged in vivo. Ion AmpliSeq Cancer Hotspot Panel v2 (Ion Torrent) was used to detect frequent somatic mutations and similarity of molecular characteristics between the 10 patient tumors and matched PDX. Histologic and immunohistochemical analyses revealed a high degree of pathologic similarity including histologic architecture and expression of CEA, CK7, and CD20 between the patient and xenograft tumors. In 80% cases, all of the somatic mutations detected in primary tumor were concordantly detected in PDX models. However, 2 PDX models showed gained mutations such as PIK3CA or FBWX7 mutation. Ten patient-derived advanced colon cancer xenograft models were established. These models maintained the key characteristic features of the original tumors, suggesting useful tool for preclinical personalized medicine platform.

β-Catenin activated hepatocellular adenoma: a report of three cases in Korea

Hepatocellular adenoma (HCA) is an uncommon benign hepatic tumor, and the use of oral contraceptives is known to contribute to the development of HCA. Recently, a genotype and phenotype classification system for HCA was suggested, and malignant transformation to hepatocellular carcinoma (HCC) was shown to be strongly associated with activating mutations in β-catenin. Here, we report three cases of HCA in Korean patients: 7-cm, inflammatory and β-catenin-activated HCA with HCC transformation in a 46-year-old man; 13-cm, β-catenin-activated HCA with cytological atypia in a 23-year-old woman; and 10-cm, pigmented, inflammatory and β-catenin-activated HCA in a 36-year-old man. All cases exhibited the nuclear expression of β-catenin and diffuse cytoplasmic expression of glutamine synthetase upon immunohistochemical staining. All tumors were completely resected, and the patients were followed for 3 to 6 years with no evidence of local recurrence or metastasis.

Human cutaneous protothecosis: report of a case and literature review

The Prototheca species is achlorophyllic algae and rarely causes human infection. Human protothecosis presents clinically as a cutaneous infection, olecranon bursitis, and disseminated systemic disease. We report a case of human cutaneous protothecosis involving the left wrist. A 68-year-old man presented with an ill-defined erythematous lesion with crust at the dorsal aspect of his left wrist. A punch biopsy was performed to reveal the histologic features of granulomatous inflammation with necrosis at the upper dermis, containing Prototheca organisms, of which, the characteristic features were highlighted by special staining. Through a molecular study, the Prototheca zopfii species was identified.

A fibrous stromal component in hepatocellular carcinoma reveals a cholangiocarcinoma-like gene expression trait and epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the major primary liver cancers in adults. The phenotypic overlap between HCC and CC has been shown to comprise a continuous liver cancer spectrum. As a proof of this concept, a recent study demonstrated a genomic subtype of HCC that expressed CC-like gene expression traits, such as CC-like HCC, which revealed the common genomic trait of stem-cell-like properties and aggressive clinical outcomes. Scirrhous HCC (S-HCC), a rare variant of HCC, is characterized by abundant fibrous stroma and has been known to express several liver stem/progenitor cell markers. This suggests that S-HCC may harbor common intermediate traits between HCC and CC, including stem-cell traits, which are similar to those of CC-like HCC. However, the molecular and pathological characteristics of S-HCC have not been fully evaluated. By performing gene-expression profiling and immunohistochemical evaluation, we compared the morphological and molecular features of S-HCC with those of CC and HCC. S-HCC expresses both CC-like and stem-cell-like genomic traits. In addition, we observed the expression of core epithelial-mesenchymal transition (EMT)-related genes, which may contribute to the aggressive behavior of S-HCC. Overexpression of transforming growth factor beta (TGF-β) signaling was also found, implying its regulatory role in the pathobiology of S-HCC.

CONCLUSION

We suggest that the fibrous stromal component in HCC may contribute to the acquisition of CC-like gene-expression traits in HCC. The expression of stem-cell-like traits and TGF-β/EMT molecules may play a pivotal role in the aggressive phenotyping of S-HCC. (HEPATOLOGY 2012;55:1776-1786).

A fibrous stromal component in hepatocellular carcinoma reveals a cholangiocarcinoma-like gene expression trait and epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the major primary liver cancers in adults. The phenotypic overlap between HCC and CC has been shown to comprise a continuous liver cancer spectrum. As a proof of this concept, a recent study demonstrated a genomic subtype of HCC that expressed CC-like gene expression traits, such as CC-like HCC, which revealed the common genomic trait of stem-cell-like properties and aggressive clinical outcomes. Scirrhous HCC (S-HCC), a rare variant of HCC, is characterized by abundant fibrous stroma and has been known to express several liver stem/progenitor cell markers. This suggests that S-HCC may harbor common intermediate traits between HCC and CC, including stem-cell traits, which are similar to those of CC-like HCC. However, the molecular and pathological characteristics of S-HCC have not been fully evaluated. By performing gene-expression profiling and immunohistochemical evaluation, we compared the morphological and molecular features of S-HCC with those of CC and HCC. S-HCC expresses both CC-like and stem-cell-like genomic traits. In addition, we observed the expression of core epithelial-mesenchymal transition (EMT)-related genes, which may contribute to the aggressive behavior of S-HCC. Overexpression of transforming growth factor beta (TGF-β) signaling was also found, implying its regulatory role in the pathobiology of S-HCC.

CONCLUSION

We suggest that the fibrous stromal component in HCC may contribute to the acquisition of CC-like gene-expression traits in HCC. The expression of stem-cell-like traits and TGF-β/EMT molecules may play a pivotal role in the aggressive phenotyping of S-HCC. (HEPATOLOGY 2012;55:1776-1786).

Changes in liver stiffness measurement during antiviral therapy in patients with chronic hepatitis B

BACKGROUND/AIMS

The usefulness of liver stiffness measurement (LSM) for monitoring changes in fibrosis and inflammation in chronic hepatitis B (CHB) patients receiving antiviral therapy is unknown. The aim of this study was to evaluate changes in liver stiffness and correlate them with changes in serological markers and histology in CHB patients receiving entecavir.

METHODOLOGY

The study included 38 patients with CHB and 24 cirrhotic patients with CHB. All patients received entecavir for over 12 months. Liver stiffness was measured by transient elastography at baseline and after 48wks of therapy. Liver biopsy was performed on 15 patients at baseline and during therapy.

RESULTS

Among 62 treated patients, 51 (82.2%) achieved HBV DNA <50 copies/mL and 43 (69%) achieved alanine aminotransferase (ALT) normalization at 48wks. The median liver stiffness value at baseline was 15.1 kPa (5.6-75.0) and decreased significantly to 8.8kPa (3.0-33.8) after 48wks. A decrease in liver stiffness value during therapy correlated significantly with decreases in albumin (r=-0.357, p=0.004), bilirubin (r=0.342, p=0.007), ALT (r=0.319, p=0.012), and aspartate aminotransferase (AST) (r=0.353, p=0.005) concentrations. Decreases in liver stiffness values correlated significantly with improvement in necroinflammatory scores.

CONCLUSION

We suggest that LSM can reflect the changes of necroinflammation in patients with chronic hepatitis B receiving antiviral therapy.

Acquisition of a BCR-ABL1 transcript in a patient with disease progression from MDS with fibrosis to AML with myelodysplasia-related changes

The 2008 WHO classification tentatively introduced myelodysplastic syndrome with fibrosis (MDS-F) based on previous literature of the existence of such cases. Most MDS-F cases have increased blasts, lower hemoglobin and platelet counts, an aggressive clinical course, and more frequently include cytogenetic aberrations. We report the case of a 66-year-old male patient diagnosed with refractory anemia with excess blasts-2 with fibrosis (MDS RAEB-2-F) with a normal karyotype and negative findings for both BCR-ABL1 transcript and JAK2 V617F mutations. He refused therapy upon his diagnosis and, after 5 months, his disease progressed to leukemia. The patient was diagnosed with acute myeloid leukemia with myelodysplasia-related changes (AML-MRC), based on a bone marrow exam revealing increased blasts (32.8%). Cytogenetic study revealed a complex karyotype, and molecular studies identified a minor BCRABL1 fusion transcript. The patient's general condition deteriorated despite the initiation of induction chemotherapy, and he died approximately 2 weeks after the diagnosis of AML-MRC. This patient's poor clinical outcome may have been exacerbated by the acquisition of the BCR-ABL1 fusion transcript overlapping with the aggressive nature of MDS-F.

Non-invasive assessment of changes in liver fibrosis via liver stiffness measurement in patients with chronic hepatitis B: impact of antiviral treatment on fibrosis regression

BACKGROUND

Liver stiffness measurement (LSM) can assess liver fibrosis in patients with chronic hepatitis B (CHB). We evaluated whether LSM can be used to assess changes in liver fibrosis during antiviral treatment using nucleos(t)ide analogs in patients with CHB.

METHODS

We recruited 41 patients with CHB who had significant liver fibrosis, normal or slightly elevated serum alanine aminotransferase (ALT) levels (≤2 × upper limit of normal), and detectable serum hepatitis B virus DNA before antiviral treatment. Patients in Group 1 (n = 23) and Group 2 (n = 18) underwent follow-up LSM after antiviral treatment for 1 and 2 years, respectively.

RESULTS

The mean age, ALT and LSM value of all patients (34 men and 7 women) before antiviral treatment were 46.6 ± 9.5 years, 40.6 ± 17.2 IU/L and 12.9 ± 8.6 kPa, respectively. Hepatitis B e antigen (HBeAg) was detected in 31 patients (75.6%). Fibrosis stage was F2 in 12 (29.3%), F3 in 6 (14.6%) and F4 in 23 (56.1%) patients. After antiviral treatment, LSM values and DNA positivity decreased significantly as compared to baseline (P = 0.018 and P < 0.001 in Group 1; P = 0.017 and P < 0.001 in Group 2, respectively), whereas ALT levels were unchanged (P = 0.063 in Group 1; P = 0.082 in Group 2).

CONCLUSIONS

Our preliminary data suggest that LSM can be used to assess liver fibrosis regression after antiviral treatment using nucleos(t)ide analogs in patients with CHB.

The application of markers (HSP70 GPC3 and GS) in liver biopsies is useful for detection of hepatocellular carcinoma

BACKGROUND/AIMS

Liver biopsy for hepatocellular carcinoma (HCC) detection is largely restricted to small hepatocellular lesions, which are often morphologically challenging, requiring careful distinction between dysplastic nodules (high-grade) and well-differentiated HCC.

METHODS

We investigated the diagnostic accuracy of a panel of markers (HSP70 GPC3 and GS), previously tested in resection specimens, in a series of liver biopsies of large regenerative nodules (n=13), low-grade dysplastic nodules (n=21), high-grade dysplastic nodules (n=50), very well-differentiated (VWD) (n=17), well-differentiated (WD-G1) (n=40) and G2-3 (n=35) HCC.

RESULTS

Almost all cases of large regenerative and low-grade dysplastic nodules did not stain while high-grade dysplastic nodules showed 1 marker (22%) but never 2 or 3. For HCC detection the overall accuracy of marker combination was 60.8% (3 markers) and 78.4% (2 markers) with 100% specificity. When restricted to VWD+WD-G1 HCC the accuracy was 57% (3 markers) and 72.9% (2 markers) with 100% specificity.

CONCLUSIONS

This panel proved useful to detect well-differentiated HCC in biopsy. Two immunoreactive markers (out of 3) are recommended as the most valuable diagnostic combination for HCC detection. The diagnostic accuracy of the panel could be improved using additional markers, as suggested by studies of expression profiling in other human models.

Cytologic features of metastatic lymphoepithelial carcinoma in pleural fluid: a case report

BACKGROUND

Lymphoepithelial carcinoma of the salivary gland is a rare undifferentiated or poorly differentiated squamous cell carcinoma associated with abundant inmphocytes. Only a handful of reports descibe the cytologic features of fine needle aspiration in lymphoepithelial carcinoma of the salivary gland and lymph nodes.

CASE

A 29-year-old man presented with a painless mass in his right parotid gland. After the surgical specimen was evaluated, the mass was diagnosed as a lymphoepithelial carcinoma, which extended to the periglandular soft tissue with lymph node metastasis. Despite radiation and chemotherapy, multiple mediastinal lymph node metastases, including in the right hilar lymph nodes, occurred. Pulmonary atelectasis of the right upper lobe and a right pleural effusion developed. Aspiration cytology of metastatic lymph nodes and pleural effusion cytology both demonstrated strongly cohesive clusters of tumor cells. These cells had vesicular nuclei and prominent nucleoli admixed with benign lymphoid cells.

CONCLUSION

Pleural effusion cytopathology ofmetastatic lymphoepithelial carcinoma is similar to that of primary tumor fine needle aspiration. Therefore, a specific diagnosis of lymphoepithelial carcinoma is possible on the basis of body fluid with these cytologic features.

Human papillomavirus type 59 identified in a verrucous cyst of the flank

The verrucous cyst is a non-plantar epidermoid cyst with histopathological features of human papillomavirus (HPV) infection, including papillomatosis and hypergranulosis of the cyst lining. We report the first case of a verrucous cyst demonstrating not only the histopathological and immunohistochemical features of HPV infection, but also homology with HPV type 59 on HPV genotyping. A 28-year-old male developed a palpable mass in his right flank. Histological examination revealed an intradermal cyst lined by an acanthotic and papillomatous squamous epithelium with prominent keratohyaline granules and squamous eddies. The keratinocyte nuclei were positive for papillomavirus antigens on immunohistochemistry and HPV genotyping demonstrated a homology to HPV type 59, a high-risk genital type. Although we only experienced a single case with such a finding, we suggest that it may be necessary to subject patients with verrucous cysts to a closer follow up for better characterization of their clinical behavior.

Galactoceles mimicking suspicious solid masses on sonography

OBJECTIVE

The purpose of this study was to evaluate the sonographic appearance of a galactocele that can sonographically mimic a suspicious solid mass and to differentiate between a galactocele and a solid mass.

METHODS

From September 2002 to February 2004, 33 galactoceles classified as Breast Imaging Reporting and Data System category 4 were included. They were all confirmed by sonographically guided core biopsies. Their sonographic imaging and clinical findings were reviewed retrospectively.

RESULTS

The lesions had a round or irregular shape in 26 patients (78.8%), a noncircumscribed margin in 31 (93.9%), a nonparallel orientation in 22 (66%), and posterior shadowing in 13 (39.4%). Twenty-five nodules (75.8%) had internal hypoechogenicity or mixed echogenicity. Twenty-nine (87.9%) of 33 lesions showed a relatively sharp convex echogenic rim on the anterior or posterior wall.

CONCLUSIONS

Galactoceles have various sonographic findings, many of which are similar to those of suspicious solid breast masses. However, there is a tendency for a galactocele to appear as a small, round hypoechoic nodule with an indistinct or microlobulated margin and mild posterior shadowing. It is helpful to search for a partial anterior or posterior echogenic rim to identify a galactocele.

Chondrosarcoma of the head and neck

Chondrosarcoma of the head and neck region is a rare disease, representing approximately 0.1% of all head and neck neoplasms. The 5-year survival rate of chondrosarcoma is 70-80%, showing relatively good prognosis; however, it is known to progress slowly and eventually cause multiple metastases. In this study, we reviewed chondrosarcoma cases experienced at Yonsei University Medical College during the last 15 years to investigate its clinical characteristics and treatment outcome. The medical records of 8 patients who were diagnosed with chondrosarcoma of the head and neck region and underwent surgical treatment between December 1990 and December 2002 were retrospectively reviewed. The primary sites were sinus, mastoid, jugular foramen and thyroid cartilage. In all patients, the initial treatment modality was surgery, and postoperative radiation therapy was performed in 4 cases. The pathological findings showed chondrosarcoma in 7 cases and mesenchymal chondrosarcoma in 1 case. The treatment outcome resulted in 3 cases of recurrence, of which 2 cases were treated successfully and the other case expired of disease, indicating a survival rate of 87.5%. In the case that resulted in death, complete excision could not be achieved. Therefore, we concluded that wide excision is a beneficial initial treatment of this rare disease.