Unusual Case of Postmenopausal Diffuse Endometriosis Mimicking Metastastic Ovarian Malignancy

Interference of Known or Suspected Endometriosis in Reporting FDG PET/CT Performed in Another Indication

INTRODUCTION

Endometriosis is a common gynecologic condition that may be visualized on 18F-FDG PET/CT and mimic lesions of malignancy. We analyzed the interference of known or suspected endometriosis in reporting 18F-FDG PET/CT performed in another indication.

RESULTS

The PET/CT images of 18 women with known (n = 15) or suspected (n = 3) endometriosis were analyzed. Based on clinical follow-up and results of other imaging, biopsy, and/or postsurgical histology, the presence of lesions of endometriosis at the time of 18F-FDG PET/CT was confirmed in 13 of 18 patients (72%). The per-patient positivity rate of 18F-FDG PET/CT was 8/18 (44%; 95% confidence interval, 22%-69%). The patient-based detection rate of 18F-FDG PET/CT in patients with confirmed lesions of endometriosis was 8/13 (62%; confidence interval, 32%-86%). On per-lesion/site basis, 18F-FDG PET/CT detected 11 of 20 sites (55%) of endometriosis. The SUVmax of these lesions/sites ranged between 1.8 and 5.3 (median, 3.8). In 9 of 18 patients (50%), a total of 13 non-endometriosis-related lesions/sites were detected by 18F-FDG PET/CT; their SUVmax ranged between 2.7 and 23 (median, 9.4).

CONCLUSION

The interference of known or suspected endometriosis in reporting 18F-FDG PET/CT performed in another indication was limited but possible and should be kept in mind, even in postmenopausal women, as the oldest patient with 18F-FDG-positive endometriosis was aged 63 years. The lesions of endometriosis showed inconstant 18F-FDG uptake with overlap of SUVmax with low-grade malignancies. In our series, the greatest SUVmax value of lesion of endometriosis was 5.3, somewhat higher than the threshold of 4 previously proposed for identification of malignant transformation of endometriosis.

Age‐dependent phenotypes of ovarian endometriomas

Purpose

To analyze the characteristics of the ovarian endometrioma (OE) across the life span of a woman. In the past, the OE has traditionally been viewed as a single, monolithic disease. Today, there are emerging data indicating that OE phenotypes differ according to the age of the woman.

Method

A narrative review of original articles on OE indexed by PubMed.

Results

When appearing in infancy and early adolescence, OE may be the consequence of endometrial cells retrogradely shed with neonatal uterine bleeding. The post‐menarcheal variant, manifesting itself during full adolescence, is singularly frequent in the presence of vaginal or uterine outflow obstructive anomalies. The typical and most frequent adult phenotype is characterized by increasing fibrosis and a tendency to progress; its mere presence exerts a detrimental effect on the surrounding healthy ovarian tissue. In postmenopause, an old lesion may be reactivated in the presence of exogenous or endogenous estrogens, or even be produced ex novo; rarely, it can spread to a variety of organs and structures and even degenerate causing malignancies.

Conclusions

Given the existence of these variants, it is important to agree on management guidelines that take into consideration these different phenotypes.

Traditionally, ovarian endometriomas are considered rightfully as one subtype of endometriosis that is different from other subtypes. Beyond that, it is considered as a monolithic disease entity. In this review, we synthesized published data and argue that this subtype actually has age‐dependent phenotypes, and as such, management should be ideally tailored to achieve the best results.

18F-FDG PET/CT Imaging of Peritoneal Fibrosis Mimicking Persistent Metastatic Ovarian Carcinoma

A 65-year-old woman was addressed for clinical and biological suspicion of ovarian cancer relapse. ¹⁸F-FDG PET/CT revealed massive peritoneal carcinomatosis. Post-chemotherapy PET/CT showed complete metabolic response in initial localizations albeit three new ¹⁸F-FDG uptakes appeared in the mesentery and in the retro-hepatic space. Close follow-up (including PET/CT scan) and surgical examination of the abdominal cavity confirmed the absence of malignancy and the benign nature of these lesions, which appeared to be peritoneal fibrosis mimicking persistent carcinomatosis.

Postmenopausal endometriosis, where are we now?

PURPOSE OF REVIEW

Postmenopausal endometriosis is a gynecologic disease, affecting 2-5% of postmenopausal woman. Current literature assessing the prevalence, pathogenesis, and treatment of this uncommon condition is limited, stressing the necessity for future research. This review examines the current literature on postmenopausal endometriosis to help inform clinical decision-making and point to novel approaches for treatment and management.

RECENT FINDINGS

Although one unifying theory to explain the pathogenesis of endometriotic lesions has not been elucidated, estrogen dependence is central to the pathophysiological process. The total quantity of estrogen production is mediated by multiple enzymes in complex pathways. Recent studies have confirmed the presence of these necessary enzymes in endometriotic lesions thereby suggesting a local source of estrogen and a likely pathogenic contributor. More research is needed to fully elucidate the mechanism of local estrogen biosynthesis; however, the current data provide possible explanations for the presence of postmenopausal endometriosis in an otherwise systemically hypoestrogenic environment.

SUMMARY

All suspected endometriosis lesions should be surgically excised for optimization of treatment and prevention of malignant transformation. If hormone replacement therapy is initiated, combined estrogen and progestin is recommended, even in the setting of previous hysterectomy, given the risk of disease reactivation and malignant transformation of endometriotic lesions. Further research is needed to understand the true prevalence, cause, and progression in this patient demographic. Histologic studies evaluating tissue lesions and peritoneal fluid for estrogen receptors, estrogen metabolizing enzymes, immune cells, and nerve fibers will aide in clinical management and treatment planning.

Symptomatic endometriosis developing several years after menopause in the absence of increased circulating estrogen concentrations: a systematic review and seven case reports

Background

To review women with symptomatic and clinically progressive endometriosis after menopause in the absence of estrogen intake or excessive systemic endogenous production.

Design

Seven case reports and a systematic review of the literature from 1995 till February 2018.

Results

Only 7 case reports from the authors and 29 cases from the literature described women with either cystic ovarian or deep endometriosis. Severity, symptoms, and localization are highly variable. No case report describes symptomatic superficial typical lesions. In 22 of 36 women (61%), symptoms started more than 10 years after menopause.

Conclusions

Symptomatic and clinically progressive endometriosis after menopause in the absence of increased systemic estrogen concentrations or exogenous estrogen intake starts more than 10 years after menopause in the majority of women. This observation suggests that a genetic and/or epigenetic incident caused estrogen-independent progression, increased sensitivity to estrogens or increased local production of estrogens. This observation is important for understanding the pathophysiology of endometriosis, for the management of postmenopausal endometriosis, and for individualization of medical therapy of endometriosis since estrogen-independent endometriosis growth probably also occurs before menopause.

Endometriosis resembling endometrial cancer in a postmenopausal patient

Endometriosis occurs in 2-4% of postmenopausal women. There have been a few reports of endometriosis in women in whom neither history nor diagnostic imaging indicated the presence of this disease, either at reproductive age or after menopause. A case is described of an 84-year-old patient with extensive deep pelvic endometriosis imitating advanced neoplastic process.

Endometriosis Mimicking an Advanced Malignant Tumor

A 27-year-old woman with swelling left leg, groin pain, and increased serum CA125 level underwent FDG PET/CT to evaluate a pelvic mass revealed by an MRI performed from an outside hospital. A large hypermetabolic solid mass in the left pelvic wall and several lymph nodes with elevated FDG activity were noted, which indicated malignancy. However, histopathological examination demonstrated endometriosis.

Ovarian Hyperstimulation and Oocyte Harvesting Prior to Systemic Chemotherapy-A Possible Pitfall in 18F-FDG PET/CT Staging of Oncologic Patients

A 33-year-old woman with Hodgkin disease Ann Arbor stage IIA underwent baseline F-FDG PET/CT scanning. The scan showed gross multicystic enlargement of both ovaries and a nodule at the edge of the right ovary with intense FDG uptake (SUVmax = 14.8). Differential diagnosis would include ovarian lymphoma manifestation, endometrioma, and ovarian or pelvic neoplasia. However, chart analysis revealed previous superstimulation with gonadotropins and gonadotropin release hormone antagonist, and transvaginal oocyte retrieval the day before FDG PET/CT. This led to the diagnosis of ovarian hyperstimulation syndrome, with the FDG-avid focus representing a hemorrhagic follicle after transvaginal oocyte retrieval procedure.