Tumeurs stromales gastro-intestinales (GIST) de taille limitée (inférieure à 5cm) : revue de la littérature et propositions pour la prise en charge

Challenge of gastro-intestinal stromal tumor management in low-income countries: example of Benin

BACKGROUND

GISTs are rare tumors but the most frequent mesenchymal tumors of the digestive tract. Diagnosis and treatment are challenging in low-income countries due to relatively poor access to immunohistochemistry and targeted therapy. In Africa, there are few studies about it. Imatinib, an oral targeted therapy, has been available in Benin since 2010 and free since 2016. This study describes the diagnosis and therapeutic management of GIST in Cotonou, Benin.

METHODS

This is a descriptive cross-sectional study, with retrospective data collection over a 10-year period from 2010 to 2020, focused on patients with histological confirmed gastro-intestinal stromal tumor (GIST). Cases were identified using the registry database and the archival files of the Hubert Koutoukou Maga National University Hospital of Cotonou (CNHU-HKM).

RESULTS

Fifteen GISTs were identified during the study period. The median age was 52 and the sex ratio was 2:1 (10 males and 5 females). The most frequent symptom was abdominal pain (n = 12). Delay in care seeking after onset of symptoms ranged from 24 h to 15 years. The most common site for GISTs was the stomach (n = 8). The median tumor size was 11 cm and the majority (n=10) was metastatic or locally advanced at the time of diagnosis. The tumors were often spindle-shaped at histology (n = 13) and the majority expressed KIT (n = 14). Most of the tumors (n = 12) were at high risk of recurrence according to the Joensuu scoring system. The availability of imatinib has improved the outcome of GIST with response in all cases it was used in neoadjuvant setting (n = 7).

CONCLUSION

GISTs are rare tumors and preferentially affect the stomach in Cotonou). Most of the tumors were large, unresectable at the time of diagnosis and at high risk of recurrence. Access to imatinib has revolutionized the management of those tumors in our country.

The Outcome of Neoadjuvant Imatinib Therapy Combined With Surgery for Rectal Gastrointestinal Stromal Tumors: A Report of Three Cases and a Review of the Literature

Gastrointestinal stromal tumors (GISTs) represent the most frequent mesenchymal tumors of the gastrointestinal tract. They occur most frequently in the stomach. Rectal localization remains rare and represents only 5% of all GIST cases and 0.1% of all rectal tumors. Immunohistochemical staining (CD117, DOG1) and molecular analysis remain the gold standard for diagnosis; DOG1 represents a very sensitive marker regardless of CD117 expression. Complete en-bloc resection constitutes the only curative treatment; however, surgical management of rectal GIST remains challenging and can involve extensive surgery such as abdominoperineal resection with significant morbidity. The role of neoadjuvant Imatinib therapy in rectal GISTs is controversial and mainly indicated in a locally advanced tumor or sphincter invasion to increase the chance of complete resection and sphincter preservation. Herein, we report three cases of a rectal GIST treated with neoadjuvant Imatinib therapy and who underwent extensive surgery with complete resection (R0), as well as a recent review of the literature, to study clinicopathological features, surgical challenges, and perioperative Imatinib therapy outcome of rectal GISTs.

Gastrointestinal stromal tumours (GISTs): French Intergroup Clinical Practice Guidelines for diagnosis, treatments and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO)

BACKGROUND

This document is a summary of the French Intergroup guidelines regarding the management of gastrointestinal stromal tumours (GISTs) updated in December 2018.

DESIGN

This collaborative work summarizes clinical practice recommendations (guidelines) on the management of GISTs. It is based on recent literature review, ESMO recommendations and expert opinions.

RESULTS

The diagnosis of GIST is based on histological examination and immunohistochemistry with markers KIT and DOG-1. Each case must be discussed within a multidisciplinary team. Complete surgical resection tumour, avoiding peroperative perforation, is the potentially curative treatment of localized GISTs. The estimation of the recurrence risk is essential, or adjuvant treatment,and follow-up adaptation. Genotyping (KIT and PDGFRA) of all but very low-risk GISTs is recommended. The nature of mutation has a prognostic value and predictive influence on drug efficacy. Imatinib, a tyrosine-kinase inhibitor, is the standard adjuvant treatment after R0 resection of a GIST with a high risk of recurrence, and the first line therapy for advanced GISTs. Suninitib and regorafenib are respectively the second- and third-line standard treatments for advanced GISTs.

CONCLUSION

Guidelines for management of GISTs are continuously evolving and need to be regularly updated. This constant progress is made possible through clinical and translational research.

[Gastrointestinal stromal tumors]

Gastrointestinal stromal tumors (GIST) are the most common sarcomas of the gastrointestinal tract. They affect all segments of the digestive tract. They develop from the interstitial cells of Cajal. Mutations in the Kit gene is present in 86% of cases and in PDGFR gene in 15% of cases. The marker CD 117 is present in 95% of cases. Surgery is the standard treatment in localized forms. The tyrosine kinase inhibitor, imatinib is standard in first-line metastatic gastrointestinal stromal tumors, as well as adjuvant treatment after surgery. Sunitinib is the standard in second line.