A rare cause of severe dyspareunia: a case report and literature review

Perforated rectosigmoid colon resulting from gastrointestinal stromal tumor presenting with peritonitis: A case report

INTRODUCTION

Colorectal perforations can arise from various causes. The most common cause of the colorectal perforations is diverticulitis, while tumors account for only a small part. Perforations frequently occur in older patients, particularly in the sigmoid colon, and distinguishing between those caused by diverticulitis and colorectal cancer can be clinically challenging. Gastrointestinal stromal tumors (GISTs) account for a small percentage of gastrointestinal malignancies, and rectal perforation due to GISTs is rare but can lead to severe complications such as peritonitis.

CASE PRESENTATION

A 55-year-old male with a medical history of hypertension and urethral stones presented with left lower quadrant abdominal pain for two days. Abdomen computed tomography (CT) revealed perforation of rectosigmoid colon, leading to an anterior resection and loop ileostomy due to short transverse colon. Postoperative histological examination identified GIST through KIT (CD117) and DOG-1 staining. The tumor was staged as pT2N0M0 (stage I), and classified as high risk in NIH criteria.

DISCUSSION

Differentiating between colorectal cancer perforation and diverticulitis is challenging, but CT findings like the absence of diverticula and shouldered edges help distinguish them. Sigmoid colon perforation due to GISTs is rare, often caused by tumor rupture. Early surgical resection with clear margins and adjuvant therapy like Imatinib improve survival rates. For colorectal perforations, immediate surgery is essential to prevent life-threatening complications like peritonitis and ensure optimal outcomes.

CONCLUSION

Accurate differentiation between malignancy-related colonic perforation and diverticulitis is vital. Early recognition, prompt surgery, and tailored treatment are key in managing perforated rectal GISTs.

Gastrointestinal stromal tumors arising in the perianal and perineal region: Two case reports and literature review

INTRODUCTION AND IMPORTANCE

Gastrointestinal stromal tumor (GIST) is rare because of its variable clinical incidence reported (from 0.4 to 2/100,000 per year) in the literature, mainly occurs primarily in the stomach and small intestine. GISTs in the perianal and perineal regions have been reported in a few pieces of literature. GIST located in the perianal and perineal regions may be misdiagnosed and missed due to atypical symptoms. We report two cases of GIST in rare sites and hope to reduce the occurrence of such events through a review of the relevant literature.

CASE DESCRIPTION

We reported two cases of GIST located in the perianal and perineal regions with different symptoms. One case underwent an emergency procedure to stop bleeding and resect the mass, and the other case was discovered during the physical examination and slowly grew in the follow-up. Following the completion of the relevant examination, the patient underwent surgical resection. Both cases were finally diagnosed as GIST by immunohistochemistry.

CLINICAL DISCUSSION AND CONCLUSION

Due to atypical clinical symptoms of perianal and perineal GIST, definitive diagnosis depends on pathology and immunohistochemistry, which can lead to misdiagnosis and missed diagnosis. Surgical resection is the preferred option for localized masses. Surgical resection of GIST located in the perianal and perineal regions requires an appropriate surgical approach based on the patients' actual condition, taking into account the protection of anal function and complete resection of the mass. Masses located in perianal and perineal region should be taken seriously by clinicians.

Mutational spectrum and therapy response of metastasized GIST in Central Switzerland - a population-based study

BACKGROUND

Until now, no population-based studies investigated the mutational status of primary GIST (PT) and corresponding metastases and correlated these data with response to Imatinib or Sunitinib therapy.

PATIENTS AND METHODS

In a retrospective observation study, all metastatic GISTs of the last 15years of our institution were investigated for mutations in c-kit and in PDGFRα gene in each PT and corresponding metastasis. Correlation with clinical outcome and response to Imatinib or Sunitinib therapy was performed.

RESULTS

In 13 PT c-kit mutations in exon 9 (3), exon 11 (7) and exon 13 (1), 2 wild type genotypes, and no PDGFRα mutation were detected. In three metastases a switch from heterozygosity to homozygosity and one additional exon 13 mutation was observed. All 10 persons with available follow-up received Imatinib as first-line chemotherapy. Five of them (3 exon 9 mutations, 1 wild type, 1 additional exon 13 mutation) stopped Imatinib due to tumour progression. In three cases, Sunitinib as second-line chemotherapy was ended due to the same reasons.

CONCLUSIONS

Our data support previous observations, that PDGFRα mutations play no important role in metastasized GISTs. The influence of Imatinib and Sunitinib therapy in metastasized GISTs with wild type genotype and c-kit exon 9 mutations needs further investigation.

Gastrointestinal stromal tumor presenting as a rectovaginal mass. Clinicopathologic and molecular-genetic characterization of a rare tumor with a literature review

Rectal gastrointestinal stromal tumors are rare. To date, 12 gastrointestinal stromal tumors have been reported as pelvic vaginal masses. We describe a rectovaginal tumor in a 39-year-old woman. The tumor frequently recurred after multiple surgical excisions and interrupted imatinib treatment without metastasizing. Magnetic resonance tomography demonstrated a partial response under imatinib. The patient was alive with stable disease under imatinib 44 months from initial diagnosis. Molecular analysis showed a somatic 6-base pair deletion in exon 11 of c-KIT (W557_K558del) in both the primary tumor and the third recurrence; the recurrence had an additional exon 17 mutation (N822K). Comparative genomic hybridization analysis of the primary tumor showed loss of 14q and gain of 1q. Recurrence showed complete loss of nuclear p16 expression. Molecular studies and p16 status confirmed the typical characteristics of gastrointestinal stromal tumors with an aggressive phenotype underscoring the need for a special interdisciplinary treatment and for achieving complete local excision with free margins.