What Are the CD34+ Cells in Benign Peripheral Nerve Sheath Tumors?

Abstract

This prospective study was designed to investigate whether patients with short activated partial thromboplastin times (aPTTs) have increased thrombin generation and are at increased risk for thromboembolism. During a 4-month period, routine coagulation specimens were screened for the presence of a short or normal aPTT, and, accordingly, 250 specimens were collected. Prothrombin fragment F1 + 2 (F1 + 2) was measured to evaluate thrombin activation, and a second aPTT was performed with a different reagent. Diagnoses were obtained from medical records after conclusion of sample collection. Five to 9 months later, patients were questioned on thromboembolic events during the previous 18 months by questionnaire and telephone interview. F1 + 2 and the incidence of venous thromboses were elevated significantly in the short aPTT group. Unexpectedly, patients with acute bleeding had short aPTTs, but 36% of these also had thromboembolic events during the 18 months proximal to blood collection. These findings were confirmed with the second aPTT reagent. Patients with short aPTTs have increased thrombin generation and are at increased risk for thromboembolism, mainly venous thromboses, despite the fact that a short aPTT can occur in the acute setting of bleeding.

A benign neoplasm with histopathological features of both schwannoma and retiform perineurioma (benign schwannoma-perineurioma): a report of six cases of a distinctive soft tissue tumor with a predilection for the fingers

“…This was the first published neoplasm having both perineuriomatous and peripheral nerve sheath differentiation. We again reviewed this case, which is included in our present series, and together with other five similar to identical cases they have now been studied immunohistochemically for the presence of neurofilaments and CD34, which label axons and fibroblasts in neurofibromas respectively [21,24,38]. The nonperineuriomatous parts of the tumor were immunohistochemically negative for the antibody to neurofilament proteins and histochemically negative with the Bodian method, findings which confirm that the lesions are devoid of axons.…”

Calretinin, CD34, and α-smooth muscle actin in the identification of peritoneal invasive implants of serous borderline tumors of the ovary

“…10,11 Such cells occur in large numbers in the connective tissue compartment of various anatomical locations such as the skin, gastrointestinal tract, uterine cervix, breast, pancreas, thyroid, salivary glands, and peripheral nervous system. [10][11][12][13] There is a demonstrable loss of stromal fibrocytes around deposits of invasive carcinoma and this has been shown to be partly accompanied by an increase in a-smooth muscle actin positive (a-SMA þ ) myofibroblasts in invasive colorectal adenocarcinoma, ductal adenocarcinoma of the pancreas, ductal breast cancer and squamous cell carcinoma of the uterine cervix. 10,12 This study examines if a panel of antibodies to calretinin, CD34, and a-SMA would be useful for the demonstration of the occurrence and distribution of mesothelial cells, stromal fibrocytes, and myofibroblasts as diagnostic discriminators for invasive and noninvasive peritoneal implants in SBTs of the ovary.…”

Shortened Activated Partial Thromboplastin Time May Help in Diagnosing Hereditary and Acquired Angioedema

“…venous thrombosis [22]. In our investigation, normal INR values showed that the extrinsic clotting system and the common pathway of coagulation were obviously not impaired in the HAE/AAE-C1-INH and IAE patients.…”