M. Timothy Smith

Normal and variant anatomy of the dural venous sinuses

The normal and variant anatomy of the cerebral veins and dural venous sinuses is poorly understood by many radiologists. Beginning with a discussion of cerebral venous anatomy, this review illustrates clinically pertinent anatomy of the cerebral sinovenous system. Various methods of imaging cerebral veins and dural venous sinuses are described. Techniques and pitfalls of MR venography are emphasized.

Protocol for the Examination of Specimens From Patients With Merkel Cell Carcinoma of the Skin

The College of American Pathologists offers these protocols to assist pathologists in providing clinically useful and relevant information when reporting results of surgical specimen examinations. The College regards the reporting elements in the ‘‘Surgical Pathology Cancer Case Summary (Checklist)’’ portion of the protocols as essential elements of the pathology report. However, the manner in which these elements are reported is at the discretion of each specific pathologist, taking into account clinician preferences, institutional policies, and individual practice. The College developed these protocols as an educational tool to assist pathologists in the useful reporting of relevant information. It did not issue the protocols for use in litigation, reimbursement, or other contexts. Nevertheless, the College recognizes that the protocols might be used by hospitals, attorneys, payers, and others. Indeed, effective January 1, 2004, the Commission on Cancer of the American College of Surgeons mandated the use of the checklist elements of the protocols as part of its Cancer Program Standards for Approved Cancer Programs. Therefore, it becomes even more important for pathologists to familiarize themselves with these documents. At the same time, the College cautions that use of the protocols other than for their intended educational purpose may involve additional considerations that are beyond the scope of these documents. PROTOCOL FOR THE EXAMINATION OF SPECIMENS FROM PATIENTS WITH MERKEL CELL CARCINOMA OF THE SKIN This protocol applies to Merkel cell carcinoma of cutaneous surfaces only. The seventh edition TNM staging system for Merkel cell carcinoma of the American Joint Committee on Cancer (AJCC) and the International Union Against Cancer (UICC) is recommended.

Evaluation of modern pathological criteria for positive margins in radical prostatectomy specimens and their use for predicting biochemical recurrence

To assess the interpretation of modern criteria for evaluating surgical margins (SMs), by examining the incidence of positive SMs (PSMs) and subsequent biochemical recurrence in a single‐surgeon series of radical prostatectomy (RP) at two institutions, as the criteria for determining PSMs after RP are subject to individual interpretation, and this might explain some of the variability in biochemical recurrence rates with different rates of PSMs.

MALIGNANT PERIPHERAL NERVE SHEATH TUMOR OF THE PROSTATE: A RARE MANIFESTATION OF NEUROFIBROMATOSIS TYPE 1

Malignant peripheral nerve sheath tumors of the prostate associated with neurofibromatosis are rare, with only 1 previous case reported in the medical literature. We report a case treated with radical cystoprostatectomy and low anterior resection with ileal conduit diversion.

Mucosal melanomas: Site-specific information, comparisons with cutaneous tumors, and differential diagnosis.

Melanoma of the skin is the fifth leading new cancer diagnosis, having accounted for almost 77,000 cases and more than 9000 deaths in the United States in 2013. Although cutaneous neoplasms of this type are relatively common, their mucosal counterparts are not. Mucosal melanomas comprise approximately 1.3% of all melanocytic malignancies. Although they are rare, these lesions present at an advanced stage with more adverse prognoses. In addition, at a molecular level, they have proven to be distinct entities because they possess genetic mutations not usually seen in their cutaneous counterparts. Conversely, a sizable proportion of mucosal melanomas lack the gene aberrations seen in cutaneous melanomas. Such findings indicate different pathways in tumorigenesis for the two subtypes. Because melanomas arising from the mucosae are not often encountered, very little has been published on staging guidelines and prognostic factors. This causes dilemmas for both patients and physicians. Further work is necessary to define staging systems for all mucosal locations, so that accurate prognoses can be assigned to such lesions.

Clinical Utility of Concurrent Single-Nucleotide Polymorphism Microarray on Fresh Tissue as a Supplementary Test in the Diagnosis of Renal Epithelial Neoplasms

OBJECTIVES The histologic and immunohistochemical variability of renal epithelial tumors makes classification difficult; with significant clinical implications, efforts to make the proper diagnoses are necessary. Single-nucleotide polymorphism (SNP) microarray analysis has been proposed as a supplementary study for the classification of renal epithelial neoplasms; however, its practical use in the routine clinical setting has not been explored. METHODS Surgical pathology cases that were classified histologically as renal epithelial tumor subtypes and had concurrent SNP microarray were retrospectively reviewed to correlate tumor morphology and SNP microarray results. RESULTS Of the 99 cases reviewed, 88 (89%) had concordant histologic and microarray results. Four (4%) cases were unclassifiable by microarray due to uncharacteristic chromosomal abnormalities. Seven (7%) of the 99 cases had discordant microarray and histologic diagnoses, and following review of the histology, the diagnoses in two of these cases were subsequently changed. CONCLUSIONS For most cases, concurrent SNP microarray confirmed the histologic diagnosis. However, discrepant microarray results prompted review of morphology and further ancillary studies, resulting in amendment of the final diagnosis in 29% of discrepant cases. SNP microarray analysis can be used to assist with the diagnosis of renal epithelial tumors, particularly those with atypical morphologic features.

The Supratentorial Mass in an Adult

36-year-old male Pain in right eye CT of orbits demonstrated left frontal abnormality Normal neurologic exam

Metachronous Aneurysmal Bone Cysts in a Fourteen-Year-Old Girl

Aneurysmal bone cysts (ABCs) were first described by Jaffe and Lichtenstein in 19421. Eighty percent of these lesions occur during the first two decades of life2; the most common location is the metaphysis of long bones. To the best of our knowledge, only four cases of individuals with multiple ABCs occurring over a period of time (metachronous ABCs) have been described to date3-6 (Table I). The cases all have been similar in presentation, imaging, and pathology to solitary ABCs; the only difference has been regarding the sex of the patient. While solitary ABCs have been shown to be predominant in females (62%)7, the reported cases of metachronous ABCs have all occurred in males. We report the case of an adolescent girl with multiple ABCs presenting separately in the proximal part of the femur and the distal part of the humerus over a five-month period. The patient and her parents were informed that data concerning the case would be submitted for publication, and they provided consent. View this table: TABLE I Reported Cases of Metachronous Aneurysmal Bone Cysts A healthy and active fourteen-year-old girl presented to the sports medicine clinic with unilateral hip pain. She had no history of trauma or an activity-related injury. Radiographs demonstrated a well-defined (5.4 × 2.8 cm) oval lucent geographic lesion in the proximal part of the femur, which initially was thought to be consistent with a unicameral bone cyst. At the short interval follow-up, the pain had worsened, and a new palpable mass was noted. Additional radiographs revealed substantial interval progression of the lesion with extension into the adjacent soft tissues with expansion of the bone (Fig. 1). Fig. 1 Anteroposterior radiograph demonstrates a lucent geographic lesion with a well-defined border (black arrow) in the right hip. However, there is focal extension …

The Infratentorial Intra-axial Tumor

Central cerebellar tumor, which heterogeneously enhances, is dark on T1 and bright on T2 (but not as bright on FLAIR). The cyst fluid is bright on T2.