Daniela Allende

Morphologic and Molecular Characterization of Traditional Serrated Adenomas of the Distal Colon and Rectum

Of the serrated polyps, the origin, morphologic features, molecular alterations, and natural history of traditional serrated adenomas (TSAs) are the least understood. Recent studies suggest that these polyps may arise from precursor lesions. The frequencies of KRAS and BRAF mutations vary between these studies, and only 1 small study has measured CpG island methylation using current markers of methylation. Mutations in GNAS, a gene commonly mutated in colorectal villous adenomas, have not been fully evaluated in TSAs. Finally, the expression of annexin A10 (ANXA10), a recently discovered marker of sessile serrated adenomas/polyps, has not been studied in these polyps. To further characterize these polyps, 5 gastrointestinal pathologists reviewed 55 left-sided polyps diagnosed as TSA at a single institution. Pathologists assessed various histologic features including cytoplasmic eosinophilia, ectopic crypt foci, presence of conventional dysplasia, and presence of precursor serrated lesions. KRAS, BRAF, and GNAS mutational analysis was performed, as well as CpG island methylation and ANXA10 immunohistochemistry. Ectopic crypt foci were seen in 62% of TSAs. Precursor lesions were seen in 24% of the study polyps, most of which were hyperplastic polyps. KRAS and BRAF mutations were common and were present in 42% and 48% of polyps, respectively. GNAS mutations occurred in 8% of polyps, often in conjunction with a BRAF mutation. Unlike sessile serrated adenomas/polyps, TSAs rarely had diffuse expression of ANXA10. Importantly, BRAF-mutated TSAs had more widespread methylation of a 5-marker CpG island panel compared with KRAS-mutated polyps. However, ectopic crypt foci, a proposed defining feature of TSA, were not associated with any specific molecular alteration.

Metanephric adenoma and solid variant of papillary renal cell carcinoma: common and distinctive features

To evaluate morphological and immunohistochemical (IHC) features helpful in distinguishing metanephric adenoma (MA) from solid papillary renal cell carcinoma (s‐PRCC).

Wegener's granulomatosis of the breast: a rare entity with daily clinical relevance

Wegeners granulomatosis (WG) is frequently diagnosed based on respiratory and renal manifestations. Breast involvement is rare. To date, approximately 27 cases of breast involvement by WG have been published. Most cases present in women between the third and seventh decades are unilateral and are accompanied by systemic manifestations of the disease. Although breast tissue is rarely affected by WG, the clinical presentation of these lesions requires that breast carcinoma be excluded from the clinical differential diagnosis. This publication is the most extensive review of the entity in the English literature in the last 3 decades.

Laparoscopic resection of rectal cancer results in higher lymph node yield and better short-term outcomes than open surgery: a large single-center comparative study.

BACKGROUND: Prognosis in rectal cancer is closely related to mesorectal integrity, margin status, and adequate lymph node dissection. The impact of laparoscopy on the pathologic and short-term outcomes remains controversial. OBJECTIVE: We aim to compare the pathologic and short-term outcomes of laparoscopic and open resections for rectal cancer. DESIGN: This is a large single-center retrospective comparative study using a prospective database. PATIENTS: All patients who underwent primary resections for rectal cancer from January 2007 to September 2011 were identified. MAIN OUTCOME MEASURES: Pathologic (nodal harvest, mesorectal integrity, circumferential, and distal margins) and operative outcomes were measured. RESULTS: Two hundred thirty-four (mean age, 61 years; 65% male) patients underwent resections for primary rectal cancer, including 118 laparoscopic (99 restorative proctectomies, 19 abdominoperineal resections) and 116 open (69 restorative proctectomies, 47 abdominoperineal resections) resections. Both groups were similar in demographics, comorbidities, and tumor characteristics. The laparoscopic group had significantly more lymph nodes (26 vs 21, p = 0.02) than the open group, with no differences in circumferential margins, proportion of distal resection margins <l cm, and completeness of total mesorectal excision. The impact of laparoscopic resection on lymph nodes was also observed for restorative proctectomy (27 vs 21, p = 0.03). Furthermore, obese and laparoscopic-converted patients had equivalent pathologic outcomes for laparoscopic and open resection. Laparoscopy was associated with longer operative time (245 vs 213 minutes, p = 0.002); less blood loss (284 vs 388 mL, p = 0.0l); shorter incisions (8 vs 20 cm, p = 0.0001) and hospital stay (7 vs 8 days, p = 0.05); and lower rates of 30-day morbidity (25% vs 43%, p = 0.04) and wound infections (9 vs 20%, p = 0.04). On multivariate regression, laparoscopic resection and year of surgery were the only independent predictors of greater lymph node harvest. CONCLUSIONS: Laparoscopy for primary rectal cancer is associated with a greater number of lymph nodes as well as short-term benefits.

Granulomas in Crohn's disease: does progression through the bowel layers affect presentation or predict recurrence?

Aim  The aim of the study was to correlate the presence and pattern of distribution of granulomas in resected specimens to clinical characteristics and outcome in patients undergoing surgery for Crohn’s disease.

Risk for esophageal neoplasia in Barrett's esophagus patients with mucosal changes indefinite for dysplasia.

Patients with Barretts esophagus (BE) are at increased risk for esophageal adenocarcinoma (EAC) and therefore require surveillance. Biopsies are classified as indefinite for dysplasia (IND) when the significance of epithelial abnormalities is uncertain due to inflammation or sampling. Our aim was to characterize the neoplastic risk of IND in BE patients and to identify predictors of neoplastic risk.

Factors influencing circumferential resection margin in rectal cancer

Aim  Abdominoperineal excision (APR) has been associated with higher circumferential resection margin (CRM) involvement and local recurrence rates than extralevator APR for low rectal cancer. This study aimed to evaluate the CRMs in APR and low anterior resection (LAR) specimens and to identify factors influencing CRM involvement.

Primary lymphoepithelioma-like carcinoma of the ureter

Lymphoepithelioma-like carcinoma (LELC) is an uncommon tumor of the urinary tract. We present a case of LELC involving the ureter of a 71-year-old male patient with gross hematuria. On biopsy, the patient was diagnosed with invasive poorly differentiated carcinoma, with a final diagnosis of LELC on subsequent nephroureterectomy. On resection, the neoplasm was solitary and consisted of undifferentiated neoplastic cells demonstrating a syncytial growth pattern, vesicular nuclei, prominent nucleoli, and an admixed polyclonal lymphoid infiltrate. Immunohistochemistry showed that the tumor cells were positive for Cam5.2 and CK7; focally positive for cytokeratinAE1/3, EMA, CK20, and p63; and negative for CK903. Epstein-Barr virus in situ hybridization was negative. No disease progression was noted at 5-month follow-up. Only 6 previous cases of LELC involving the ureter have been reported in the literature. We document an additional example of this uncommon entity and present a comprehensive review of LELC involving the ureter.

Ganglioneuroma of the adrenal gland.

THE spectrum of tumors arising from the embryonal sympathetic nervous system includes neuroblastoma, ganglioneuroblastoma and ganglioneuroma, with the latter representing the most differentiated tumor in this category. Ganglioneuroma is one of the most common sympathetic nervous system tumors in adults. Ganglioneuromas originate in association with the sympathetic nervous system chain, primarily located in the posterior mediastinum and retroperitoneum. Up to 30% of these tumors occur in the adrenal gland and it has been postulated that they are derived from neuroblasts in the adrenal medulla. The incidence of adrenal ganglioneuroma is low with only 8 of 97 adrenal tumors resected during a 10-year period diagnosed as ganglioneuroma in 1 report. In contrast to lesions in the retroperitoneum and posterior mediastinum, which often affect younger patients, ganglioneuromas in the adrenal gland tend to occur in the 4th and 5th decades of life. No gender predilection has been reported. Clinically ganglioneuroma is often an incidental finding. However, up to 37% of these tumors can produce catecholamines or other hormones such as vasoactive intestinal peptide with associated severe diarrhea and rarely testosterone with accompanying virilization. Although most ganglioneuromas are

Inter-observer and intra-observer variability in the diagnosis of dysplasia in patients with inflammatory bowel disease: correlation of pathological and endoscopic findings

Colonic epithelial dysplasia is deemed the precursor lesion of cancer arising in inflammatory bowel disease (IBD). It has been suggested that many dysplastic lesions could be endoscopically detected to obtain target biopsies, leading to better yield. However, the clinical impact of a diagnosis of dysplasia may be hampered by a significant degree of histological and endoscopic intra‐observer and inter‐observer variability. This study aimed to evaluate intra‐observer and inter‐observer variability in the microscopic diagnosis of dysplasia in IBD and correlate endoscopic and histological findings.