Primary leiomyosarcoma of the colon: a case report and review of the literature

High grade leiomyosarcoma of the transverse colon with positive lymph node metastasis: to treat or not to treat with adjuvant radiation therapy?

Intra-abdominal leiomyosarcomas (LMSs) are aggressive malignant tumours arising from smooth muscle cells. These neoplasms are extremely rare and account for 10%-20% of primary soft tissue sarcomas and approximately 0.1% of all colorectal malignancies. Intra-abdominal LMS has a very poor prognosis with an estimated 5-year survival rate between 20% and 50% and the size of the tumour being the main determinant of prognosis. Treatment is further complicated by different anatomic variants with differing clinical behaviours impacting prognosis. Newer techniques in radiation treatment such as intensity-modulated, intraoperative electron and proton beam radiotherapies allow for cases with high probability of local recurrence or likelihood of residual microscopic disease after surgical resection to be treated with precise radiation doses to the targeted tumour volume. We present a case of high grade LMS of the distal transverse colon with positive lymph node metastasis treated by surgical excision followed by adjuvant radiotherapy and discuss the current role of radiotherapy.

Unexpected Origin of Lung Metastases: Rare Colon Leiomyosarcoma Detected by 18F-FDG PET/CT

ABSTRACT

A 49-year-old woman was referred to our hospital due to suspected lung metastases for 1 month. She had a history of thyroid micropapillary carcinoma and uterine leiomyomas. An 18F-FDG PET/CT scan, which was performed to search the source of the presumed metastasis of the disease, showed multiple lung metastases and 2 18F-FDG-avid foci in the thyroid and colon. Biopsy of lung and resection of colon lesions were then performed, and the disease was finally identified to be rare primary colon leiomyosarcoma with multiple lung metastases.

Curative resection of leiomyosarcoma of the descending colon with metachronous liver metastasis: A case report

BACKGROUND

Leiomyosarcoma (LMS) has a poor prognosis and rarely originates from the colon. If resection is possible, surgery is the first treatment most commonly considered. Unfortunately, no standard treatment exists for hepatic metastasis of LMS; although, several treatments, such as chemotherapy, radiotherapy, and surgery, have been used. Subsequently, the management of liver metastases remains controversial.

CASE SUMMARY

We present a rare case of metachronous liver metastasis in a patient with LMS originating from the descending colon. A 38-year-old man initially reported abdominal pain and diarrhea over the previous two months. Colonoscopy revealed a 4-cm diameter mass in the descending colon, 40 cm from the anal verge. Computed tomography revealed intussusception of the descending colon due to the 4-cm mass. The patient underwent a left hemicolectomy. Immunohistochemical analysis of the tumor revealed that it was positive for smooth muscle actin and desmin, and negative for cluster of differentiation 34 (CD34), CD117, and discovered on gastrointestinal stromal tumor (GIST)-1, which are characteristic of gastrointestinal LMS. A single liver metastasis developed 11 mo post-operatively; the patient subsequently underwent curative resection thereof. The patient remained disease-free after six cycles of adjuvant chemotherapy (doxorubicin and ifosfamide), and 40 and 52 mo after liver resection and primary surgery, respectively. Similar cases were obtained from a search of Embase, PubMed, MEDLINE, and Google Scholar.

CONCLUSION

Early diagnosis and surgical resection may be the only potential curative options for liver metastasis of gastrointestinal LMS.

Giant leiomyosarcoma of the transverse colon

Leiomyosarcoma (LMS) of the colon accounts for <1% of all colorectal malignancies. Our patient was a 72-year-old man with a history of aortic valvular disorder and congestive heart failure, who presented with an abdominal mass and no constitutional symptoms. The CT scan finding suggested a large tumour with both solid and cystic components. Intraoperatively, a portion of the involved colon was resected along with the tumour. Microscopically, the tumour was found to invade the muscularis propria layer of the transverse colon. The final diagnosis was LMS, FNCLCC grade 2 of 3 based on the histology and immunochemistry.

A pooled analysis of risk factors of surgically treated leiomyosarcoma of the colon in adults

Background

This current systematic review aimed to evaluate the role of surgical management and risk factors by pooled cases from all identified patients with colonic leiomyosarcomas.

Methods

The authors searched the Ovid MEDLINE, Embase, PubMed, and Cochrane databases using the keywords “colonic,” “colon,” and “leiomyosarcoma.” Risk factors of colonic leiomyosarcoma in the pooled cohort were also evaluated.

Results

Between 1923 and 2019, 41 cases of colonic leiomyosarcoma were identified in 22 (53.7%) males and 19 (46.3%) females, with a mean and median age of 58.7 ± 2.2 years and 56.0 years. According to univariate analysis, smaller tumor size < 8 cm was significantly associated with longer progression-free survival (HR = 6.957, 95% CI 1.405–34.442; p = 0.017), and younger age < 60 years was trending toward better overall survival (HR = 2.765, 95% CI 0.924–8.272; p = 0.069).

Conclusions

Colonic leiomyosarcomas are rare neoplasms with aggressive clinical behaviors. Age < 60 years and tumor size < 8 cm were favorable factors for patients’ better survival.