Imaging in gynecological disease (19): clinical and ultrasound features of extragastrointestinal stromal tumors (eGIST)

Pancreatic Extragastrointestinal Stromal Tumor: A Case Report

Gastrointestinal stromal tumors (GISTs) are soft tissue sarcomas that originate from the mesenchymal cells of the gastrointestinal tract. Extra-GISTs (EGISTs) are caused by sites outside the gastrointestinal tract. We reported a case of EGIST of the pancreas in a 51-year-old woman. Enhanced CT scan showed a rounded, slightly hypointense focus in the head of the pancreas and the right pars compacta of the descending duodenum. Routine laboratory and endocrine tests were unremarkable. The patient underwent laparoscopic surgery. The diagnosis of EGIST was confirmed through histopathological and immunohistochemical examination. The tumor was found to be CD117+, CD34+, and DOG+ with a high risk of malignancy. No recurrence was observed during the nine-month postoperative follow-up.

Imaging in gynecological disease (26): clinical and ultrasound characteristics of benign retroperitoneal pelvic peripheral-nerve-sheath tumors

OBJECTIVE

To describe the clinical and sonographic characteristics of benign, retroperitoneal, pelvic peripheral-nerve-sheath tumors (PNSTs).

METHODS

This was a retrospective study of patients with a benign, retroperitoneal, pelvic PNST who had undergone preoperative ultrasound examination at a single gynecologic oncology center between 1 January 2018 and 31 August 2022. All ultrasound images, videoclips and final histological specimens of benign PNSTs were reviewed side-by-side in order to: describe the ultrasound appearance of the tumors, using the terminology of the International Ovarian Tumor Analysis (IOTA), Morphological Uterus Sonographic Assessment (MUSA) and Vulvar International Tumor Analysis (VITA) groups, following a predefined ultrasound assessment form; describe their origin in relation to nerves and pelvic anatomy; and assess the association between their ultrasound features and histotopography. A review of the literature reporting benign, retroperitoneal, pelvic PNSTs with preoperative ultrasound examination was performed.

RESULTS

Five women (mean age, 53 years) with a benign, retroperitoneal, pelvic PNST were identified, four with a schwannoma and one with a neurofibroma, of which all were sporadic and solitary. All patients had good-quality ultrasound images and videoclips and final biopsy of surgically excised tumors, except one patient managed conservatively who had only a core needle biopsy. In all cases, the findings were incidental. The five PNSTs ranged in maximum diameter from 31 to 50 mm. All five PNSTs were solid, moderately vascular tumors, with non-uniform echogenicity, well-circumscribed by hyperechogenic epineurium and with no acoustic shadowing. Most of the masses were round (n = 4 (80%)), and contained small, irregular, anechoic, cystic areas (n = 3 (60%)) and hyperechogenic foci (n = 5 (100%)). In the woman with a schwannoma in whom surgery was not performed, follow-up over a 3-year period showed minimal growth (1.5 mm/year) of the mass. We also summarize the findings of 47 cases of benign retroperitoneal schwannoma and neurofibroma identified in a literature search.

CONCLUSIONS

On ultrasound examination, no imaging characteristics differentiate reliably between benign schwannomas and neurofibromas. Moreover, benign PNSTs show some similar features to malignant retroperitoneal tumors. They are solid lesions with intralesional blood vessels and show degenerative changes such as cystic areas and hyperechogenic foci. Therefore, ultrasound-guided biopsy may play a pivotal role in their diagnosis. If confirmed to be benign PNSTs, these tumors can be managed conservatively, with ultrasound surveillance. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

High negative prediction for the Basel sarcoma score: Sonographic assessment of features suspicious of uterine sarcoma

INTRODUCTION

In the management of uterine myomas, laparoscopic surgery with morcellation enables a minimal invasive procedure. Cases of unsuspected uterine sarcoma dissemination have been reported and led to regulative restrictions. To help to distinguish preoperatively myomas from sarcomas, we assessed the value of six sonographic criteria (Basel Sarcoma Score, BSS) in a prospective outpatient cohort of consecutive patients with uterine masses.

MATERIAL AND METHODS

We prospectively evaluated all patients presenting with myoma-like masses planned for surgery with standardized ultrasound examination. BSS including the following criteria was investigated: rapid growth in past three months, high blood flow, atypical growth, irregular lining, central necrosis and oval solitary lesion. For each criterion, a score 0/1 was given. BSS (0-6) equals the sum of all given scores. Histological diagnosis was used as reference.

RESULTS

Among 545 patients, 522 had the final diagnosis of myoma, 16 had peritoneal masses with sarcomatous components (PMSC), and seven had other malignancies. Median BSS for PMSC was 2.5 (range: 0-4) vs 0 for myomas (range: 0-3). The most common sonographic criteria leading to a false positive score in myomas were rapid growth in past three months and high blood flow. For the detection of sarcomatous masses with BSS threshold of >1, sensitivity was 93.8%, specificity 97.9%, and positive predictive value (PPV) and negative predictive value (NPV) were 57.7% and 99.8%, respectively (AUC 0.95).

CONCLUSION

BSS can help distinguishing between myomas and sarcomatous masses, with high NPV. Caution is required when >1 criterion is present. As a simple tool, it could easily be integrated into routine myoma sonographic examination and help develop standardized assessment of uterine masses for better preoperative triage.

Extra-Gynecological Pelvic Pathology: A Challenge in the Differential Diagnosis of the Female Pelvis

Ultrasound technology with or without color Doppler allows a real-time evaluation of the entire female pelvis including gynecologic and non-gynecological organs, as well as their pathology. As ultrasound is an accurate tool for gynecological diagnosis and is less invasive and less expensive than other techniques, it should be the first imaging modality used in the evaluation of the female pelvis. We present a miscellany of non-gynecological pelvic images observed during the realization of gynecological ultrasound. Transvaginal and transabdominal ultrasound is the first choice among diagnostic techniques for the study of the female pelvis, providing information about gynecological and extra-gynecological organs, allowing for an orientation toward the pathology of a specific organ or system as well as for additional tests to be performed that are necessary for definitive diagnosis.

Malignant epithelioid neoplasm of the ileum with ACTB-GLI1 fusion mimicking an adnexal mass

BACKGROUND

Malignant epithelioid neoplasm with ACTB-GLI1 fusion are considered different from the more common pericytic lesions, such myopericytoma, because they have a spectrum of different genetic abnormalities. They appear to pursue a benign clinical course in young adults, although in sporadic cases lymph node metastasis were described. The categorization of this new type of tumor may also lead to new therapeutic strategies, because they might be sensitive to SHH pathway inhibitors.

CASE PRESENTATION

The case involves a 72-years-old multiparous woman who accessed our department after an incidental finding of a right adnexal mass of 43 mm with contrast-enhancement on a control computed tomography scan made for suspected diverticulitis. Our intervention was a detailed ultrasound description of the suspected neoplasm; a diagnostic laparoscopy and the contextual laparotomic removal of abdominal mass; its histological and immunohistochemical analysis. Our main outcome measure is the definition and future recognition of new pathologic entity called malignant epithelioid neoplasm with ACTB-GLI1 fusion.

CONCLUSIONS

We described for the first time the ultrasound characteristic of this type of lesion using standardized terminology and we believe that it may be the first step to improve the acknowledgement of this novel pathologic entity defined as malignant epithelioid neoplasm with GLI-1 fusions.