Nongynecologic XXXX : a potential mimic of tubal high-grade serous @entity189 or nonmucinous @entity1373 .

@entity851 @entity706 @entity5 @entity1373 @entity189 @entity2615 @entity876 @entity5274 @entity4648 @entity3 @entity420
Mucosal alterations of the fallopian tube are generally thought to represent alterations of the native tubal mucosal epithelium, whether benign or malignant. The current paradigm implicating the fallopian tube fimbriae as the origin of most pelvic high-grade serous @entity189 (HGSCs) is based on the premise that HGSC growing within the tubal mucosa originated there. This has fueled proposals to redefine classification rules for assigning the primary site of origin on the basis of the presence or absence of HGSC in the tubal mucosa. The corollary is that it is unlikely for @entity189 to @entity5274 . Evidence to support or refute this corollary is minimal, in part because the fallopian tubes historically have been ignored. This study reports the pattern and topography of 100 nongynecologic @entity5 that metastasized to the fallopian tubes. Most @entity5 were @entity420 (87%), and the remainder included @entity706 , and @entity2615 . The most common primary origins of @entity5 were the colon (35%) and breast (15%). Gross evidence of a tubal nodule or mass was only seen in 35% of cases. Ovarian @entity3 were present in 95% of cases, although 23% did not exhibit gross evidence of @entity3 . @entity5 involved the fimbriae in 49% of cases, including 10% of cases in which the @entity5 was restricted to the fimbriae without involving the nonfimbriated portion of the tube. The anatomic distribution of @entity3 included the tubal mucosa (29%), submucosa (43%), muscularis (54%), serosa (76%), lymphovascular spaces (38%), intraluminal space (16%), and mesonephric remnants (39%). The most common architectural pattern of @entity851 was a flat layer (22/29 cases), followed by varying degrees of stratification, tufting, and papillary growth. High-grade atypia was present in 18/29 cases of @entity851 , resulting in patterns that resembled primary tubal HGSC. Accompanying growth in the tubal submucosa frequently produced a pseudoinvasive pattern mimicking invasive tubal HGSC. Immunohistochemical expression of @entity876 by 8/18 high-grade mucosal @entity3 further contributed to the resemblance to primary tubal HGSC. Bland cytology was present in 11/29 cases of @entity851 , some of which also exhibited mucinous features, resulting in patterns that resembled either @entity4648 or nonmucinous @entity1373 . Although uncommon, it is possible for @entity3 of nongynecologic @entity5 to @entity5274 and create a potential diagnostic pitfall. Intramucosal growth of a @entity5 in the fallopian tube is not pathognomonic of a primary tubal origin of the @entity5 . These findings may carry implications for proposed criteria using the status of the fallopian tube mucosa to assign primary origin of a @entity5 .
