Kaposi Sarcoma Mimicking a Lingual Lesion in an HIV-Negative Patient: A Case Report.

Tonsillar Kaposi sarcoma is rare, reported in patients with human immunodeficiency virus (HIV) infection. This case report of a tonsillar Kaposi sarcoma (KS) in an HIV-negative male patient, initially misinterpreted as a lingual lesion diagnosed with KS following tonsillectomy, highlights the value of a differential diagnosis in atypical presentations. The case report discusses the etiologic agent of KS, its detection and treatment, and a few case reports about tonsillar KS with no association with AIDS.

Detection of High-Grade Prostate Cancer With a Super High B-value (4000 s/mm2) in Diffusion-Weighted Imaging Sequences by Magnetic Resonance Imaging.

Introduction: High-grade adenocarcinoma of the prostate tends to have denser glandular structures and a prominent desmoplastic reaction, which could be detected by magnetic resonance imaging (MRI) with a super-high b-value in diffusion-weighted imaging (DWI) sequence, to differentiate it from low-grade carcinomas.

Objective: To evaluate the diagnostic validity of the diffusion sequence with values ​​of b4000 s/mm2 for the diagnosis of high-grade prostate cancer (Gleason score ≥ 7).

Materials And Methods: It is a retrospective analytical study of male patients who have undergone a prostate biopsy and count with a prostate MRI with a DWI sequence of a super-high b-value (4000 s/mm2).

Immunohistochemistry, Quality Control, and Principles of Validation in the Central Nervous System.

The conventional hematoxylin and eosin stain (H&E) is vital for the histological diagnosis but the role of immunohistochemistry (IHC) in the central nervous system is undeniable. Immunohistochemical techniques detect antigens in tissue sections by immunological and chemical reactions. This chapter reviews the preanalytic, analytic, and postanalytic phases of immunohistochemistry, as well as the principles of quality control and validation.

Sensitivity and Specificity of Ultrasonography Using Ovarian-Adnexal Reporting and Data System Classification Versus Pathology Findings for Ovarian Cancer.

Background One of the limiting factors for early diagnosis of ovarian neoplasms is the lack of standardized terminology for ultrasound. The Ovarian-Adnexal Reporting and Data System (O-RADS) classification aimed to reduce variability between observers and facilitate communication with attending physicians. Recent studies show that O-RADS has higher sensitivity (96.

Malignant paraganglioma (multiple, multicentric and metastatic) in a female patient with family history of paraganglioma.

Malignant paragangliomas are rare, but may occur especially in patients with familial forms of the disease. We present the case of a 23 year old woman diagnosed with bilateral carotid paraganglioma with distant and local metastases, associated to a family history of paraganglioma and we present a literature review.

[Immunohistochemical Expression of CD117 (c-kit) in 75 Renal Cell Tumors].

Objective: c-kit encodes the membrane-bound tyrosine kinase c-kit, whose expression has been identified in several human neoplasms. We analyzed the immunohistochemical expression of c-kit in renal cell tumors.

Methods: 75 cases of renal cell tumors were obtained from the surgical pathology archives at the ABC Medical Center in Mexico, for the period 2001 to 2011.

Primary pleural hybrid cellular schwannoma/perineurioma: a case report.

Hybrid schwannoma/perineurioma is a recently characterized benign nerve sheath tumor, most commonly affecting the lower limb and limb girdle. Hybrid tumors located in the subcutis of the trunk have not previously been reported to affect the pleura. We describe a 52-year-old man with dyspnea and thoracic pain due to a large mass in the right pleura, histologically composed of densely packed, S-100-positive spindle cells, intermixed with cells containing slender nuclei positive for epithelial membrane antigen, Glut-1, and claudin-1.

[Metastatic oropharyngeal squamous cell carcinoma in cervical lymph nodes associated to HPV infection type 16 and 45; clinical, morphological and molecular study of two cases].

Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma has been identified as a distinct entity within squamous cell carcinoma of the head and neck. In contrast to carcinomas associated with alcohol and/or tobacco, this subtype occurs at younger age, with frequent absence of classic risk factors, correlation with oral sexual habits, strong predilection for the palatial tonsils and the base of the tongue (lingual tonsils), basaloid or lymphoepithelial differentiation, higher degree of radiosensitivity, and overall better survival. We report two cases of lymph node, metastatic, poorly differentiated squamous cell carcinoma that were positive by immunohistochemistry for p16 with detection of HPV-16 and HPV-45 by PCR.

Primary monophasic synovial sarcoma of the tonsil: immunohistochemical and molecular study of a case and review of the literature.

Synovial sarcoma (SS) arises primarily in the lower extremities with a predilection for sites in proximity to large joints, such as the knee. It rarely occurs in the head and neck region, and the tonsil is an unusual site for the tumor, with only eight previously published cases in this anatomical site. We present a case of a primary monophasic SS arising in the right tonsil in a 63-year-old male.

[Immunohistochemical comparison between GCDFP-15 and estrogen and progesterone receptors in the diagnosis of metastatic carcinoma of the breast].

Background: In the workup of tumors of unknown primary origin in women, a frequent consideration is breast carcinoma, because it is common and may initially present as metastasis.

Objective: Describe and compare the immunohistochemical profile of hormonal receptors (estrogen receptor and progesterone receptor) and GCDFP-15 in lymph node metastatic breast carcinoma according the histological grade.

Methods: Retrospective study analyzing 30 patients with identified primary breast cancer and lymph node metastasis.

Nontraumatic splenic pseudocyst. Case report.

Background: Splenic cysts are uncommon and are classified as true cysts (with epithelial lining) and false cysts or pseudocysts. Splenic pseudocysts usually have a posttraumatic origin and are secondary to hematoma or to splenic infarction. At times there is no prior evidence of trauma, and the cyst may be secondary to a primary cyst with degeneration/atrophy of the epithelial lining.

[Bilateral tonsillar hypertrophy as the first manifestation of B cell-small lymphocytic lymphoma with interfolicular pattern].

B-cell small lymphocytic lymphoma typically involves nodal or extranodal tissues as a diffuse proliferation with proliferation centers (pseudofollicules) obliterating normal architecture. But there are unusual patterns of involvement including interfollicular pattern that can be difficult to recognize histologically and probably represent partial or early involvement by neoplasm. Tonsillar lymphoma usually presents either as a unilaterally enlarged palatine tonsil or as an ulcerative and fungating lesion over the tonsillar area.