Cytokeratin 5/6 and P63 immunophenotype of thyroid lymphoepithelial complexes

Thyroid lymphoepithelial complexes (LECos) are rare, being reported in lymphoma, Graves-Basedow disease, Hashimoto thyroiditis, pericarcinomatous thyroid or in the context of branchial cleft-like cysts. Here we report immunohistochemical expression of cytokeratin 5/6, P63 and TTF1 in 6 cases of thyroid LECos. Two cases had carbimazole treatment for hyperthyroidia and Graves disease. Anti-thyroglobulin, -thyroperoxidase or -TSH antibodies were detected in 4 cases. NSAID or poviodone iodine allergy were present in 2 cases. The treatment consisted in total thyroidectomy or lobectomy. Microscopy showed nodular goiter and focal lymphocytic thyroiditis. Basaloid LECos were seen in all thyroids while squamoid LECos in 2. Associated lesions were papillary thyroid microcarcinoma (2 cases), solid cell nest, thyroglosal duct remnant, lymphoepithelial cyst and thymus-parathyroid unit (one case each). Cytokeratin 5/6 was expressed in both squamoid and basaloid LECos along with P63. TTF1 expression was faint or absent. In conclusion LECos may occur in the context of autoimmune thyroiditis or of a specific immune susceptibility background. The expression of CK5/6 and of P63 suggests a squamous differentiation including in the basaloid LECos. The etiologic relevance of these immunostainings remains limited although rather suggestive of a metaplastic process than of migration-abnormalities.

Acute Appendicitis and Pneumatosis in a Duplicated Appendix With Schistosoma Remnants

Appendiceal pneumatosis is rare, reported either in the context of acute appendicitis or enterocolitis. Here, we report the case of an elderly adult in whom the acute appendicitis was associated with pneumatosis and occurred in the context of a malformed appendix with pathogenic organism remnants. A 72-year-old man presented with abdominal pain 3 weeks after posttraumatic dorsolumbar surgery. The computed tomography scan showed acute appendicitis and 2 diverticula. On microscopy, the appendix showed acute appendicitis along with a Cave-Wallbridge type A duplication. In addition, several optically clear spaces were observed in the entire appendiceal wall consistent with pneumatosis of the appendix. Focally, calcified structures suggesting pathogenic organisms such as Schistosoma were noted as well. In conclusion, we report a case of appendiceal pneumatosis occurring in the context of acute appendicitis in a duplicated appendix, with presence of calcified structures suggestive of pathogenic organisms.

Do Osteoblastoma and Osteoid Osteoma Represent the Same Pathologic Entity?: A Case Report and Review of the Recent Literature

CASE

We present the case of a fourteen-year-old boy with a benign diaphyseal femoral lesion that initially fulfilled the diagnostic criteria for osteoid osteoma but rapidly progressed and was finally diagnosed as osteoblastoma.

CONCLUSION

Clinical and radiographic criteria provide imperfect and somewhat arbitrary distinguishing features between osteoid osteoma and osteoblastoma. Although previous work highlighted the importance of histologic interpretation in this regard, recent comparative histologic and immunohistochemical evaluations failed to differentiate the two. We conclude that consideration should be given to the classification of osteoid osteoma and osteoblastoma as the same pathologic entity, with treatment based on presentation along a continuum of aggressiveness, and that future directions for study may include identification of factors predictive of progression and/or recurrence.

Thyroid lymphoepithelial nodule

Thyroid benign lymphoepithelial lesions are rare in adults, reported as associated with thyroiditis or adjacent to tumours. Here we report a unique case of a thyroid solid nodule with benign lymphoepithelial morphology. A 56-year-old woman presented with a thyroid nodule increasing in size. Thyroid function was normal. On the surgical resection specimen, in addition to a 2-cm follicular adenoma, there was, at distance, a 0.5-cm solid nodule with lymphoepithelial morphology, without Hassal's corpuscles or calcifications. On immunohistochemistry, the epithelial component was cytokeratin 5/6 positive and very focally cytokeratin 7 positive, the immunophenotype of the lymphoid tissue confirming the benign nature. The diagnosis of thyroid benign lymphoepithelial nodule was proposed. In conclusion, recognition of thyroid solid benign lymphoepithelial nodules is important since they can be misdiagnosed with other thyroid micronodule types including carcinoma, primary or metastatic.

The role of cystectomy for non-malignant bladder conditions: a review

INTRODUCTION

Few studies have adequately addressed the indications, efficacy, and quality-of-life for cystectomy performed for non-malignant bladder conditions. Patients with debilitating non-malignant bladder conditions who have failed all previous conservative therapies may undergo various forms of cystectomy, including partial, simple or radical cystectomy. We provide a review of the current literature and recommendations for cystectomy for various non-malignant bladder conditions.

MATERIALS AND METHODS

A systematic review of MEDLINE was conducted to find prospective and retrospective studies using the keywords "cystectomy", "benign", and `non-malignant`. Articles were reviewed and triaged, background articles were added as supplements, leaving a final review of 67 papers.

RESULTS

Data from the final review suggests that common benign indications for cystectomy are interstitial cystitis/painful bladder syndrome (IC/PBS), neurogenic bladder, hemorrhagic/radiation cystitis, infectious diseases of the bladder and miscellaneous conditions of the bladder such as endometriosis and total refractory incontinence. The most common perioperative complications include urinary tract and wound infections. Efficacy of cystectomy in patients with IC/PBS is greater than 80%, while efficacy in patients with neurogenic bladder is greater than 90%. Finally, improved urinary quality-of-life has been demonstrated in patients with neurogenic bladder post-cystectomy.

CONCLUSION

Cystectomy for non-malignant conditions can be considered for patients who have failed previous conservative therapy. The limited data in existence suggests fertility can be adequately preserved after cystectomy in younger males. The data regarding the forms of urinary diversion suggests no significant advantage between any of the major forms of urinary diversion. Finally, while newer pharmacologics and technological advances are widely used in the treatment of various benign urological conditions, their role in preventing or treating refractory benign bladder conditions have not been fully characterized.

Preservation of fine-needle aspiration specimens for future use in RNA-based molecular testing

BACKGROUND

The application of ancillary molecular testing is becoming more important for the diagnosis and classification of disease. The use of fine-needle aspiration (FNA) biopsy as the means of sampling tumors in conjunction with molecular testing could be a powerful combination. FNA is minimally invasive, cost effective, and usually demonstrates accuracy comparable to diagnoses based on excisional biopsies. Quality control (QC) and test validation requirements for development of molecular tests impose a need for access to pre-existing clinical samples. Tissue banking of excisional biopsy specimens is frequently performed at large research institutions, but few have developed protocols for preservation of cytologic specimens. This study aimed to evaluate cryopreservation of FNA specimens as a method of maintaining cellular morphology and ribonucleic acid (RNA) integrity in banked tissues.

METHODS

FNA specimens were obtained from fresh tumor resections, processed by using a cryopreservation protocol, and stored for up to 27 weeks. Upon retrieval, samples were made into slides for morphological evaluation, and RNA was extracted and assessed for integrity by using the Agilent Bioanalyzer (Agilent Technologies, Santa Clara, Calif).

RESULTS

Cryopreserved specimens showed good cell morphology and, in many cases, yielded intact RNA. Cases showing moderate or severe RNA degradation could generally be associated with prolonged specimen handling or sampling of necrotic areas.

CONCLUSIONS

FNA specimens can be stored in a manner that maintains cellular morphology and RNA integrity necessary for studies of gene expression. In addition to addressing quality control (QC) and test validation needs, cytology banks will be an invaluable resource for future molecular morphologic and diagnostic research studies.

MicroRNA-17-3p is a prostate tumor suppressor in vitro and in vivo, and is decreased in high grade prostate tumors analyzed by laser capture microdissection

MicroRNAs (miRs) are a novel class of RNAs with important roles in regulating gene expression. To identify miRs controlling prostate tumor progression, we utilized unique human prostate sublines derived from the parental P69 cell line, which differ in their tumorigenic properties in vivo. Grown embedded in laminin-rich extracellular matrix (lrECM) gels these genetically-related sublines displayed drastically different morphologies correlating with their behaviour in vivo. The non-tumorigenic P69 subline grew as multicellular acini with a defined lumen and basal/polar expression of relevant marker proteins. M12, a highly tumorigenic, metastatic derivative, grew as a disorganized mass of cells with no polarization, whereas the F6 subline, a weakly tumorigenic, non-metastatic M12 variant, reverted to acini formation akin to the P69 cell line. These sublines also differed in expression of vimentin, which was high in M12, but low in F6 and P69 sublines. Analysis of vimentin's conserved 3'-UTR suggested several miRs that could regulate vimentin expression. The lack of miR-17-3p expression correlated with an increase in vimentin synthesis and tumorigenicity. Stable expression of miR-17-3p in the M12 subline reduced vimentin levels 85% and reverted growth to organized, polarized acini in lrECM gels. In vitro motility and invasion assays suggested a decrease in tumorigenic behaviour, confirmed by reduced tumor growth in male athymic, nude mice dependent on miR-17-3p expression. Analysis of LCM-purified clinical human prostatectomy specimens confirmed that miR-17-3p levels were reduced in tumor cells. These results suggest that miR-17-3p functions as a tumor suppressor, representing a novel target to block prostate tumor progression.