Squamous Metaplasia of the Ovarian Surface Epithelium and Subsurface Fibrosis: Distinctive Pathologic Findings in the Ovaries and Fallopian Tubes of Patients on Peritoneal Dialysis:

End-Stage Kidney Disease and Dialysis in Pregnancy

End-stage kidney disease is associated with low fertility, with rates of conception in women on dialysis estimated at 1/100th of the general population. However, live birth rates are increasing over time in women on hemodialysis, whereas they remain lower and static in women on peritoneal dialysis. Intensification of hemodialysis, targeting a serum blood urea nitrogen <35 mg/dL or 36 hours of dialysis per week in women with no residual kidney function, is associated with improved live birth rates and longer gestational age. Even in intensively dialyzed cohorts, rates of prematurity and need for neonatal intensive care are high, upwards of 50%. Although women on peritoneal dialysis in pregnancy do not appear to be at increased risk of delivering preterm compared with those on hemodialysis, their infants are more likely to be small for gestational age. As such, hemodialysis has emerged as the preferred dialysis modality in pregnancy. Provision of specialized nephrology, obstetric, and neonatal care is necessary to manage these complex pregnancies and family planning counseling should be offered to all women with end-stage kidney disease.

Squamous metaplasia of the peritoneum: report of a case

The ability of the peritoneum to undergo metaplasia, especially to Müllerian-type epithelium has been recognized for a long time. The ability of mesothelial cells to modulate cytoskeletal filaments and shape is provided through the distinct form of subserosal cells, called multipotential subserosal cells, that have the function of replicative cells that differentiate into surface epithelium when affected by various stimuli. Rare forms of peritoneal metaplasia include squamous and cartilaginous metaplasia. This report presents a case of fully developed, mature peritoneal squamous metaplasia in an 85-year-old woman who underwent surgery because of small bowel perforation leading to diffuse peritonitis. This rare incidental finding almost always occurs in the background of chronic peritoneal irritation as a response to mesothelial injury. Squamos peritoneal metaplasia should not be interpreted as metastatic squamous cell carcinoma. The most important distinguishing criteria are the lack of nuclear atypia, mitoses, necrosis, and desmoplastic stromal response.

Clear cell carcinoma of ovary with squamous metaplasia: A unique histopathological observation

Squamous metaplasia though is commonly associated with ovarian endometrioid neoplasm, mixed mullerian tumor and Brenner tumors; it has not been described in an ovarian clear cell carcinoma. Unusual presence of squamous islands, either in the form of morules or keratin plaques, may create diagnostic difficulty in a clear cell carcinoma of ovary, and thus the other common associations should be ruled out. Here, we describe a case of clear cell carcinoma of the ovary, with both gross and microscopically identifiable squamous metaplasia. To the best of our knowledge, this is the first report on this rare association and should be documented for wider awareness.

The expression and diagnostic utility of p63 in the female genital tract

p63 plays a key role in epithelial development in various organs, being expressed in myoepithelial cells and in basal cells of stratified epithelia. In the female genital tract, p63 is expressed in the basal and parabasal cells of mature cervical, vaginal and vulval squamous epithelium, and also in cervical reserve cells at the transformation zone and in immature metaplastic and atrophic cervical squamous epithelium. In this review, the diagnostic utility of p63 immunohistochemical staining in various pathologic scenarios within the female genital tract is discussed. Cervical microglandular hyperplasia is p63 positive with a characteristic subcolumnar location due to expression in reserve cells. There is increased expression in cervical intraepithelial neoplasia, in accordance with the degree of dysplasia. One of the most useful applications of p63 is in the evaluation of problematic cervical carcinomas; most squamous carcinomas exhibit diffuse nuclear immunoreactivity whereas most adenocarcinomas and neuroendocrine carcinomas are negative or focally positive. In conjunction with neuroendocrine markers, p63 is useful in distinguishing between a squamous carcinoma and a small cell or large cell neuroendocrine carcinoma. In the normal endometrium, a population of p63-positive cells is present which may act as a stem cell population and which is increased in various forms of metaplasia. Placental site nodule and epithelioid trophoblastic tumor (lesions derived from chorionic-type intermediate trophoblast) are usually p63 positive whereas placental site reaction and placental site trophoblastic tumor (lesions derived from implantation site intermediate trophoblast) are usually negative; thus, p63 may be useful in the diagnostic algorithm of trophoblastic lesions. p63 positivity in ovarian epithelial tumors is uncommon and largely restricted to squamous and transitional neoplasms, including benign and borderline Brenner tumor. p63 is also positive in cervical transitional metaplasia, Walthard rests, vulval Paget disease secondary to an underlying urothelial malignancy, tubulosquamous polyp of the vagina, and ectopic prostatic tissue in the cervix.