Cytology of the fallopian tube: A screening model for high-grade serous carcinoma

Abstract

Ovarian cancer is a heterogeneous disease having the highest gynecologic fatality in the United States with a 5-year survival rate of 46.5%. Poor overall prognosis is mostly attributed to inadequate screening tools, and the majority of diagnoses occur at late stages of the disease. Due to genetic and biological underpinnings, ovarian high-grade serous carcinomas (HGSC) have etiologic evidence in the distal fallopian tube. Fallopian tube screening modalities are aggressively investigated, but few describe cytological characteristics of benign tubal specimens to help in the comparative detection of HGSC precursor cells. Here, we describe fimbrial cytomorphological and nuclear features of tubal specimens (n = 75) from patients clinically indicated for salpingectomy, bilateral or unilateral salpingo-oophorectomy, and hysterectomies for any diagnosis other than ovarian or peritoneal cancer. Fallopian tube histology was used as the diagnostic reference. A total of 75 samples had benign diagnoses. The benign cytological characteristics of fimbrial tubal specimens included ciliated cells in clustered arrangements with mild nuclear membrane irregularity, mild anisonucleosis, round and/or oval nuclei, hyperchromatic chromatin, and mild nuclear membrane irregularity. In contrast, none of the cytology samples had spindle-shaped nuclei, significantly marked anisonucleosis (n = 1), nor had hypochromasia as a characteristic feature. These cytological characteristics could be a potential area of distinction from HGSC precursor cells. Our study establishes cytomorphological characteristics of nonmalignant tubal cells which help underscore the importance of distinguishing malignant HGSC precursors through fimbrial brush sampling in minimally invasive approach.

Cytologic studies of in vivo fallopian tube specimens in patients undergoing salpingo-oophorectomy

“…[ 16 , 17 ] There have been few previous studies that characterized nonmalignant cytomorphological and nuclear features of cells collected from FTs. [ 13 - 15 ] Consistent with these previous studies, we found there was a range of variations in cytological features present in nonmalignant samples. The variations could exist in appearance of cellular or nuclear features.…”

“…showed that in women undergoing salpingo-oophorectomy, FT samples collected ex vivo yielded encouraging cytology results that highly correlated to histopathology. [ 12 ] Benign tubal cytology has been characterized in samples collected through a cytobrush both in vitro [ 13 ] and in vivo . [ 14 , 15 ] However, the in vivo sample collection efficiency was not satisfactory partly because the cytobrush was not specifically designed for collecting samples from the FT, hindering further research into utilizing FT cytology for OC detection.…”

The Utility of Fallopian Tube Cytology in the Early Detection of Extrauterine Serous Gynecological Malignancies: A Narrative Literature Review

“…Five studies with a total of 278 patients and 423 specimens were investigated. The included studies [13][14][15][16][17] showed variations in the method of obtaining the samples, the cytopreservatives used, and the stains applied for cytological analysis (Table 2). Table 2 indicates that sample obtaining was performed ex vivo in the majority of the studies (4/5), and cytological evaluation was mostly performed on Papanicolaou stains.…”

“…The most commonly used brush was the cytobrush, while an electric toothbrush repurposed as a Tubebrush© was applied on fresh specimens in one study. Nonetheless, the most recent obtaining method utilized the Cytuity™ cell collection catheter to collect samples via hysteroscopy [13][14][15][16][17].…”

“…In an attempt to assess the diagnostic ability of cytological evaluation, 5 studies [13][14][15][16][17] correlated the cytological with the histopathological diagnosis, reporting promising results in the detection of atypical and malignant alterations of the salpingeal cells. All of these studies showed a high concordance rate (81.8-100%).…”