CONDITIONS SIMULATING OVARIAN NEOPLASMS I
Low-lying distended cecum. Normally, the cecum lies in the right iliac fossa upon the iliopsoas muscle, with its apex or lowest point a little to the mesial side of the middle of the inguinal ligament. In some cases, however, the cecum hangs over the pelvic brim or is lodged entirely within the pelvic cavity. It may be mistaken for an ovarian cyst.
Redundant sigmoid colon. The sigmoid lies in close relationship to the uterine fundus within the true pelvis. When the redundant loop is ﬁlled with fecal material or gas, it may suggest the possibility of ovarian neoplasm.
Appendiceal abscess. When the cecum is low or the appendix is long, the latter may lie within the right pelvis. Should an acute appendix rupture, the resultant localized abscess may be situated in the region of the right adnexa. The pelvic ﬁndings may suggest the possibility of a hemorrhage, rupture, or torsion of an ovarian neoplasm. A low-lying, acutely inﬂamed appendix with adherent omentum may also simulate an accident involving an ovarian neoplasm.
Paraovarian cysts, derived from the vestigial remnants of the wolfﬁan body within the broad ligament, are intraligamentous. They may be small, incidental ﬁndings at operation or may grow to a large size. A paraovarian cyst should be kept in mind if a unilateral, ovoid, ﬁxed, thin-walled cyst is palpated.
Ruptured ectopic pregnancy with hematocele may, at times, be confused with an acute accident in an ovarian tumor, an enlarged cystic corpus luteum with incomplete abortion, a rupture of a graaﬁan follicle or hemorrhagic corpus luteum, an acute appendicitis with adherent omentum, or an exacerbation of a predominantly unilateral chronic adnexitis.
Distended urinary bladder. A partially ﬁlled bladder may simulate a soft, thin-walled, anteriorly located neoplasm. If tensely distended, it may suggest a large cyst or uterine pregnancy. A catheter or bedside ultrasonography will resolve the question.
Intrauterine pregnancy. The corpus of a gravid uterus is oval, smooth, soft, cystic, and movable from side to side. When the isthmic portion of the uterus is particularly soft (Hegar sign), it is easily compressed between the examining ﬁngers in the vagina and on the abdomen, suggesting the possibility of a cystic mass separate from the cervix. The body of a pregnant uterus in marked retroversion and retroﬂexion may similarly be mistaken for a cyst in the posterior culdesac.
Pregnancy in one horn of a bicornuate uterus is associated with slight hypertrophy of the other horn. Pelvic examination during the ﬁrst half of pregnancy may suggest the presence of a cystic mass contiguous to a slightly enlarged uterus. If a double vagina or a double cervix is found, a uterus bicornis or didelphys may be suspected.
Desmoid tumor. Situated in the hypogastric portion of the anterior abdominal wall, this tumor may, on examination, suggest a possible origin in the pelvis. Desmoids are solid, ﬁbrous, benign tumors, oval in shape, and sometimes quite large. Sarcomatous changes may occur.
Urachal cyst. As a result of the incomplete obliteration of the urachus at birth, a cystic dilation may, at times, be found in the hypogastrium. Its location in the midline between the parietal peritoneum and the anterior abdominal wall aids in the diagnosis.
Uterine fibromyomas. The presence of other multiple ﬁbromyomas is helpful but not conclusive proof of origin. A pedunculated ﬁbroid is freely movable, as are most ovarian neoplasms. Its broad attachment, however, may be traced to a portion of the uterus other than the ovarian ligament. A pedunculated ﬁbroid may undergo torsion of its pedicle with infarction and peritoneal irritation, similar to twisted ovarian cysts. Ultrasonography, computed tomography, or magnetic resonance imaging may be helpful but may not always provide an unambiguous diagnosis.