Outcomes of Primary Colorectal Sarcoma: A National Cancer Data Base (NCDB) Review

The sentinel polyp: high-grade sarcoma revealed after colonic polypectomy

An 87-year-old man presented with malaise, anorexia and postprandial vomiting for 3 days. At presentation the patient was hypotensive and tachycardic, without any other relevant findings. Laboratory workout showed a normocytic normochromic anemia of 4.9g/dl. No hematic losses from the gastrointestinal tract were described or seen. The patient underwent a colonoscopy to study the anemia and an 18mm semi-pedunculated polyp in the descendent colon was found and excised. A whole-body tomography performed during hospitalization showed multiple nodular lesions in the lungs, pleura, peritoneum and left gluteal muscle compatible with metastatic disease. The polyp histological examination was finally compatible with a high-grade undifferentiated sarcoma. Patient died during hospitalization due to disease progression and multiple complications. Colorectal sarcomas are a very rare group of mesenchymal tumours, accounting for 0,1% of all colonic cancers [1]. They usually present as a high grade and aggressive tumour and are often located in the colon (70%) comparing with the rectum. Metastization is common and more often to the liver, peritoneum and lung. Curative treatment depends on surgical resection without need of extensive lymphadenectomy due to its rare lymphatic dissemination, but prognosis is usually poor [2]. Even so, the polyp described probably reflects a metastatic lesion of an extra-colonic sarcoma and not the primary sarcoma itself. Extrapulmonary metastases, namely intra-abdominal metastases, of musculoskeletal sarcomas are rare and are associated with even poorer prognosis [3]. There are few published papers describing the presence of colonic metastases since their implantation is usually subepithelial.

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.

The importance of surgical resection in the management of rectal sarcoma: A national cancer database analysis of 133 cases

BACKGROUND AND PURPOSE

Rectal sarcomas (RS) are rare malignant tumors with a very poor prognosis. This study aimed to assess the characteristics, treatment, and outcomes of RS in the United States.

METHODS

This study was a retrospective analysis of the National Cancer Database (NCDB) from 2004 to 2019 of patients with a diagnosis of RS. The main outcome measures were overall survival (OS) and its predictors.

RESULTS

133 RS patients (39.1% female) with a mean age of 65.7 ± 15.6 years were included in the study. Mean tumor size was 6.1 ± 3 cm. The crude OS rate was 22.5% and median survival duration was 10.1 (IQR: 3.2-21) months. Factors associated with an improved OS on were private insurance (HR = 0.23, p = 0.001) and undergoing surgery (HR 0.23, p < 0.001), Factors associated with poor survival were age (HR 1.02, p = 0.005), male sex (HR 2.27, p = 0.001), Charlson score of 3 (HR 5.17, p = 0.003), and positive resection margins (HR: 2.64, p = 0.01). Multivariate Cox regression analysis revealed that male sex (HR 2.16, p = 0.04) and positive resection margins (HR 2.31, p = 0.03) were predictors of poor survival whereas surgery was an independent predictor of improved OS (HR 0.321, p < 0.001) CONCLUSIONS: RS is a very rare rectal malignancy with an even poorer prognosis than previously reported. However, undergoing surgery with curative intent while obtaining negative margins may confer better OS.

Colorectal leiomyosarcoma with BRCA2 mutation benefit from treatment with olaparib: a case report

Background

Colorectal leiomyosarcoma (LMS) is a rare colorectal malignancy accounting for approximately 1% of all colorectal malignancies with a poor prognosis and limited treatment options. Targeted therapies have been applied for breast cancer 2 (BRCA2) alterations, but their role remains to be explored in colorectal LMS. This case could provide clinical proof for the application of olaparib for LMS patients.

Case Description

Here, we present a case of colorectal LMS with BRCA2 alterations who was treated with olaparib and achieved progression-free survival (PFS) for 1 year. In August 2016, a 46-year-old female patient was admitted to hospital due to a mass in the left lower abdomen and was diagnosed with LMS of the sigmoid colon. After surgical resection, chemotherapy with ifosfamide or ifosfamide combined with pirarubicin was given and achieved stable disease (SD) until the disease progressed 1.5 years later. Afterwards, a multi-target tyrosine kinase inhibitor, anlotinib, was taken. Before the observation of lung and liver metastasis, the patient's disease was stable for 1 year. BRCA2 mutation and rearrangement was revealed by next-generation sequencing (NGS), and the targeted therapy, olaparib, was given. Efficacy evaluation showed SD for 1 year, and no obvious toxic and side effects were observed.

Conclusions

Our case suggested that NGS should be considered for further treatment of patients with colorectal LMS, and poly (ADP-ribose) polymerase (PARP) inhibitors could be a feasible therapy for LMS patients with BRCA2 alterations.

Spindle Cell Sarcoma (SCS); a case of primary leiomyosarcoma (LMS) of the sigmoid colon presented as intestinal obstruction

Leiomyosarcoma (LMS) is a common form of soft tissue sarcoma. Primary colonic LMS is an extremely rare entity, comprising 1-2% of gastrointestinal malignancies. Primary mesenchymal sarcomas of the gastrointestinal system are rare and constitute just 0.1-3% of all gastrointestinal tumours. LMS is the most common variant of such tumours and represents just 0.12% of colorectal malignancies. We present a case of a 65-year-old female, who presented to the emergency department with 3 days history of obstipation and generalized abdominal pain. Radiology (X-ray and ultrasound) indicated a large pelvic mass compressing the sigmoid colon and its surrounding structures. Histopathological analysis indicated a primary LMS of the sigmoid colon. Diagnosis is established mostly postoperatively after histopathological evaluation. Prognosis and treatment modalities for this aggressive malignancy remain insufficient. LMS is relatively impervious to chemotherapy/radiotherapy. Our patient was treated by surgical excision of the tumour and referred postoperatively for adjuvant chemotherapy.

Primary leiomyosarcoma of the sigmoid colon: Case report and review of literature

Leiomyosarcomas of the sigmoid colon are aggressive and extremely rare tumors representing less than 0.1% of all colorectal malignancies. Few cases have been reported in the literature and their imaging features need to be more detailed. We report the case of a 70 year old male patient, smoker, with a history of arterial hypertension, admitted for abdominal pain and hypogastric mass. Computed tomography has shown a voluminous heterogeneously enhancing tumor process with a necrotic center, attached to the sigmoid wall, with multiple secondary peritoneal and hepatic masses. The anatomopathological examination of the biopsy sample with immunohistochemistry allowed the diagnosis of leiomyosarcoma of the sigmoid colon. Clinical presentation and radiological features of leiomyosarcomas are non-specific, and the definitive diagnosis is only established after an anatomopathological examination.

Laparoscopic Right Hemicolectomy to Curatively Treat Primary Leiomyosarcoma at the Ileocecal Valve

Primary leiomyosarcomas of the colon (PLC) are rare tumors, representing 0.12% of all colon malignancies. We report a 59-year-old man with weight loss, mild anemia, and rectal bleeding. Colonoscopy revealed a 3.2 × 2.6-cm mass at the ileocecal valve. Histopathological examination of the biopsy showed a spindle cell neoplasm that stained positive for smooth muscle actin, caldesmon, and desmin. A diagnosis of PLC was made. Subsequently, a laparoscopic right hemicolectomy was performed, and no local recurrence was noted 6 months after the resection. Given the rarity of PLC, more studies on the clinical features and treatments of this tumor are warranted.

Outcomes of surgically managed primary lung sarcomas: a National Cancer Database analysis

Background

Primary lung sarcoma (PLS) represents a rare form of lung cancer with outcomes that are poorly defined by small datasets. We sought to characterize clinical and pathological characteristics and associated survival within the surgically managed subgroup of these unusual pulmonary malignancies.

Methods

We performed a retrospective analysis of the National Cancer Database (NCDB), which was queried for cases of surgically managed PLS diagnosed between 2004–2014. Adjusted mortality was evaluated in a multivariable Cox proportional hazards model and compared to surgically manage non-small cell lung cancer (NSCLC) patients from the same time period.

Results

A total of 695 patients with surgically managed PLS were identified with 37 different histologic subtypes. The mean age of diagnosis was 57.7 years (range, 18–90 years). A majority of patients underwent surgical resection alone (64.3%) with an estimated 5-year overall survival (OS) of 51%. The multivariable Cox model identified increasing age, Charlson-Deyo score ≥2, high tumor grade, tumor size >5 cm, positive margins, and positive lymph nodes to be associated with higher risk for mortality (P<0.05). Compared to 101,428 surgically managed patients with adenocarcinoma, PLS patients were younger with fewer comorbidities but had larger tumors, higher grade tumors, and were more likely node negative (P<0.001). Surgery with adjuvant chemotherapy was associated with worse survival than surgery alone (HR 1.41, 95% CI: 1.05–1.88). The extent of parenchymal resection (lobar vs. sublobar) was not predictive for survival. Five-year OS was lower for patients with PLS (44%) than adenocarcinoma (53.6%, P<0.001).

Conclusions

The survival of surgically managed PLS is reasonable and impacted by tumor attributes and the completeness of surgical resection. Further study to define the role of multimodal therapy is indicated.

The prognostic factors of primary colorectal sarcoma and the clinical outcomes of negative lymph node dissection

Background

Primary colorectal sarcoma is an extremely rare malignancy that is associated with poor patient outcomes. The aim of this study was to identify the prognostic factors of primary colorectal sarcoma and evaluate the clinical outcomes associated with these prognostic factors.

Methods

Between January 1, 2000 and December 31, 2016, the clinical data of 315 patients with primary colorectal sarcoma were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Cancer-specific survival (CSS) was analyzed by the Kaplan-Meier method and by log-rank test. The prognostic factors were identified by univariate and multivariate Cox regression analysis and hazard ratio (HR) and 95% confidence interval (CI) of covariates were also estimated. The optimal cutoff value for NLN count at dissection was identified using X-tile software and validated by univariate Cox regression analysis.

Results

Of the 315 patients with primary colorectal sarcoma identified, 88.6% received surgery. The median follow-up time was 34 months with an interquartile range (IQR) of 9-79 months. The 5-year rate of CSS was 76.73% and 27.8% for the surgery group and the non-surgery group, respectively (P<0.0001). Univariate and multivariate Cox regression analysis performed on the data of nonmetastatic patients demonstrated that sex, race, radiotherapy, and chemotherapy had no effect on patient CSS, with age, tumor site, tumor grade, and NLN dissection being independent prognostic factors. A significant correlation was found between advanced age (>80 years old) and poor CSS (HR 1.964; 95% CI: 1.005-3.839; P=0.048). There were also significant correlations between colonic tumors and poor CSS (HR 2.903; 95% CI: 1.348-6.250; P=0.006) and grade IV tumors and poor CSS (HR 3.431; 95% CI: 1.725-6.823; P<0.001), while NLN dissection was associated with improved CSS (HR 0.946; 95% CI: 0.911-0.983; P=0.004). X-tile software analysis was used to determine that the optimal cutoff value for NLN count was 13. Patients who received NLN dissection with a cutoff value of 13 or more displayed better CSS than those who did not (P=0.016).

Conclusions

Primary colorectal sarcoma patients can benefit significantly from primary tumor surgery. Age, tumor site, grade and NLN dissection are independent prognostic factors for CSS in nonmetastatic patients. Importantly, nonmetastatic patients treated with NLN dissection with an NLN count of 13 or more have significantly better CSS.

Surgical resection improves overall survival of patients with small bowel leiomyosarcoma

PURPOSE

Small bowel leiomyosarcoma (SB LMS) is a rare disease with few studies characterizing its outcomes. This study aims to evaluate surgical outcomes for patients with SB LMS.

METHODS

The National Cancer Database was queried from 2004 to 2016 to identify patients with SB LMS who underwent surgical resection. The primary outcome was overall survival.

RESULTS

A total of 288 patients with SB LMS who had undergone surgical resection were identified. The median age was 63, and the majority of patients were female (56%), White (82%), and had a Charlson comorbidity score of zero (76%). Eighty-one percent of patients had negative margins following surgical resection. Fourteen percent of patients had metastatic disease at the time of diagnosis. Nineteen percent of patients received chemotherapy and 3% of patients received radiation. One-year overall survival was 77% (95% CI: 72-82%) and 5-year overall survival was 43% (95% CI: 36-49%). Higher grade (HR: 1.98, 95% CI: 1.10-3.55, p = 0.02) and metastatic disease at diagnosis (HR: 2.57, 95% CI: 1.45-4.55, p = 0.001) were independently associated with higher risk of death.

CONCLUSION

SB LMS is a rare disease entity, with treatment centering on complete surgical resection. Our results demonstrate that overall survival is higher than previously thought. Timely diagnosis to allow for complete surgical resection is key, and investigation into the possible role of chemotherapy or radiation therapy is needed.

Racial/Ethnic Disparities and Survival Characteristics in Non-Pancreatic Gastrointestinal Tract Neuroendocrine Tumors

Simple Summary

The impact of race and ethnicity on survival characteristics in non-pancreatic gastrointestinal tract neuroendocrine tumors is understudied. We evaluated the survival outcomes and racial/ethnic disparities in the gastrointestinal tract neuroendocrine tumors, including the esophagus, stomach, small intestine, colon, rectum, and appendix. Survival trends were determined among three groups: Hispanic, non-Hispanic White, and non-Hispanic Black. We analyzed a large national database and found that race/ethnicity is an independent prognostic factor in patients with gastrointestinal neuroendocrine tumors. Hispanic patients had better overall survival than non-Hispanic White patients, whereas non-Hispanic Black patients had favorable cause-specific survival compared to non-Hispanic White patients. This survival disparity can be attributed to differences in the site of origin, age, and stage at presentation between various race/ethnicity. Understanding these differences between race and ethnicity is needed to reduce disparities in cancer outcomes.

Abstract

Background: We studied the effect of race and ethnicity on disease characteristics and survival in gastrointestinal neuroendocrine tumors. Methods: The Surveillance, Epidemiology, and End Results database was used to select patients with non-pancreatic gastrointestinal neuroendocrine tumors diagnosed between 2004 and 2015. Trends in survival were evaluated among three groups: Hispanic, non-Hispanic White, and non-Hispanic Black. Kaplan–Meier and Cox regression methods were performed to calculate overall survival and cause-specific survival after adjusting for patient and tumor characteristics. Results: A total of 26,399 patients were included in the study: 65.1% were non-Hispanic White, 19.9% were non-Hispanic Black, and 15% were Hispanic. Non-Hispanic White patients were more likely to be male (50.0%, p < 0.001), older than 60 years (48.0%, p < 0.001), and present with metastatic disease (17.7%, p < 0.001). Non-Hispanic White patients had small intestine neuroendocrine tumors, while Hispanic and non-Hispanic Black patients had rectum neuroendocrine tumors as the most common primary site. Hispanic patients had better overall survival, while non-Hispanic Black patients had better cause-specific survival versus non-Hispanic White patients. This finding was confirmed on multivariable analysis where Hispanic patients had improved overall survival compared to non-Hispanic White patients (Hazard ratio (HR): 0.89 (0.81–0.97)), whereas non-Hispanic Black patients had better cause-specific survival compared to non-Hispanic White patients (HR: 0.89 (0.80–0.98)). Conclusions: Race/ethnicity is an independent prognostic factor in patients with gastrointestinal neuroendocrine tumors.

Analysis of the Incidence and Clinical Features of Colorectal Nonadenocarcinoma in Korea: A National Cancer Registry-Based Study

Purpose

Although most colorectal malignancies are adenocarcinomas from mucosa, various types of malignant and benign tumors can develop. Due to extremely low incidence, little research has been conducted. The purpose was to assess incidence and compare it according to demographic factors.

Methods

Data from the Korea National Cancer Registry from 2007 to 2016 were used. The crude incidence, age-standard incidence rate (ASR) of colorectal nonadenocarcinomas were calculated.

Results

Over 11 years, there were 267,142 patients with colorectal malignancies. The patients of 14,495 (5.43%) were diagnosed with nonadenocarcinoma. The ASR was 2.52 per 100,000 in men and 1.56 in women. Lesions were classified according to histologic categories; neuroendocrine tumor (NET) was the most common malignancy (10,919 [75.33%]). Nonadenocarcinoma was the most common in 40s and 50s (40 to 49 years, 3,530 [24.35%]; 50 to 59 years, 3,991 [27.53%]). Lymphoma was high (54.46%) in patients in teenagers. Proportion of NET decreased with age and that of carcinoma increased with age. Carcinoma, sarcoma, and lymphoma were more common among men and melanoma was more common among women. The most common site was the rectum (11,066 [76.34%]). Lymphoma occurred more frequently in proximal colon. Melanoma, gastrointestinal stromal tumor, and NET occurred mostly in rectum. A total of 10,155 patients (70.06%) were classified as having localized disease.

Conclusion

This study is meaningful as it is the first study to examine incidence of colorectal nonadenocarcinoma. Differences in incidence of different lesions based on demographic factors were identified. This study will play a role in cancer prevention and diagnosis projects.

Mesenteric Lymph Node Recurrence of a Primary Colorectal Leiomyosarcoma

Primary colorectal leiomyosarcoma is an excessively rare entity. It is associated with an aggressive behavior and typically favor hematogenous spread. The current standard of care is surgical resection. A 49-year-old patient presented with a 2-month history of fever. A PET-scan revealed a hypermetabolic mass in the transverse colon, and colonoscopy confirmed a tumor. A right hemicolectomy was performed. Histopathological diagnosis was of a leiomyosarcoma. Fourteen months after the surgery, a follow-up abdominal scan revealed a 2 cm mesenteric lymph node that was hypermetabolic on PET-scan. The mesenteric lymph node was resected and histopathology confirmed a leiomyosarcoma metastasis. This case opens the controversy on the management of rare lymph node recurrences in colorectal leiomyosarcoma.

Leiomyosarcoma of the Rectum as a Radiation-Induced Second Malignancy after Cervical Cancer Treatment: Case Report with Review of the Literature

BACKGROUND

Incidence of cervical cancer among women of reproductive age still remains significantly high. In regard to prognostic features and risk factors, the standard treatment for most types of cervical cancer represents a combination of surgical treatment and radiation therapy, such as external beam radiation therapy and brachytherapy. Despite significant advances of long-term oncological outcomes, radiation-induced secondary malignancies among cervical cancer survivors are still an issue. Current case report describes an incredibly rare case of radiation-induced leiomyosarcoma of the rectum, which occurred 32 years after cervical cancer treatment.

CASE PRESENTATION

A 62-year-old female had a past medical history of FIGO stage IIB cervical cancer (squamous cell carcinoma pT2bN0M0). In 1987, she underwent radical hysterectomy with bilateral iliac lymph node dissection, followed by adjuvant radiation therapy-70 Gy external beam pelvic irradiation followed by 30.5 Gy of brachytherapy. Thirty-two years later, she presented with signs of rectal bleeding. Regarding past medical history, radiologic, endoscopic, and pathologic data, the patient was initially diagnosed with a malignant nonepithelial lower rectal tumor of the unknown origin and staged as mrT3a mrN0 cM0. Total mesorectal excision with complete mesocolic excision and central vascular ligation (CME/CVL) carried by an open approach was carried out. In an attempt to identify the tissue of origin, an immunohistochemistry assay had been performed. Tumor cells showed a high rate of mitotic activity with a 45% rate of Ki-67 expression, positive reaction for desmin, and SMA in all samples. Negative reaction for CD117 and S100 was observed. As a conclusion, the immunophenotype was identified as a grade 3 leiomyosarcoma (ISD-code 8890/3).

CONCLUSIONS

We suggest that up to date, radical surgery with curative intent, as it was performed in our study, is the most evidence-based treatment option for patients with radiation-induced sarcomas of the rectum.

Beyond adenocarcinoma: MRI of uncommon rectal neoplasms and mimickers

OBJECTIVE

To provide a review of rare rectal tumors beyond adenocarcinoma.

RESULTS

Rectal cancer is a common malignancy, both in the United States and abroad. In addition to adenocarcinoma, abdominal radiologists will encounter a variety of other less common rectal masses, both benign and malignant neoplasms as well as non-neoplastic mimickers. Familiarity with these conditions and their characteristic features on MRI is useful in clinical practice. In this article, a number of such conditions are discussed, with an emphasis on distinguishing features on MRI of the rectum.

CONCLUSION

Familiarity with the MRI features of rare rectal tumors beyond adenocarcinoma, as well as a small number of non-neoplastic mimics, is important for abdominal imagers to make diagnostic differentials and to assist in treatment planning.

The opportunities and shortcomings of using big data and national databases for sarcoma research

The rarity and heterogeneity of sarcomas make performing appropriately powered studies challenging and magnify the significance of large databases in sarcoma research. Established large tumor registries and population-based databases have become increasingly relevant for answering clinical questions regarding sarcoma incidence, treatment patterns, and outcomes. However, the validity of large databases has been questioned and scrutinized because of the inaccuracy and wide variability of coding practices and the absence of clinically relevant variables. In addition, the utilization of large databases for the study of rare cancers such as sarcoma may be particularly challenging because of the known limitations of administrative data and poor overall data quality. Currently, there are several large national cancer databases, including the Surveillance, Epidemiology, and End Results database, the National Cancer Data Base of the American College of Surgeons and the American Cancer Society, and the National Program of Cancer Registries of the Centers for Disease Control and Prevention. These databases are often used for sarcoma research, but they are limited by their dependence on administrative or billing data, the lack of agreement between chart abstractors on diagnosis codes, and the use of preexisting documented hospital diagnosis codes for tumor registries, which lead to a significant underestimation of sarcomas in large data sets. Current and future initiatives to improve databases and big data applications for sarcoma research include increasing the utilization of sarcoma-specific registries and encouraging national initiatives to expand on real-world, evidence-based data sets.

Colorectal sarcoma: more than a gastrointestinal stromal tumor

Primary colorectal sarcomas have been defined as a rare and diverse group of mesenchymal cancers distinct from gastrointestinal stromal tumors (GISTs). Primary colorectal sarcomas have been recognized as a distinct entity from GISTs due to the dramatically worse prognosis these sarcomas carry. Also, primary colorectal sarcomas when compared to the more common colorectal adenocarcinoma, demonstrate more aggressive biology, present at a younger age and carry worse outcomes. At this time, surgery remains the mainstay of treatment and adjuvant chemotherapy has an unclear role in treatment of primary colorectal sarcoma. This paper attempts to review the available data regarding primary colorectal sarcomas.

National cancer database analysis of outcomes in pediatric glioblastoma

Glioblastoma in children is an aggressive disease with no defined standard therapy. We evaluated hospital‐based demographic and survival patterns obtained through the National Cancer Database to better characterize children with glioblastoma. Our study identified 1173 patients from 0 to 19 years of age between 1998 and 2011. Comparisons were made among demographics, clinical characteristics, treatment, and survival variables. Fifty‐four percent of patients were over 10 years of age. Approximately 80% of patients underwent either partial or complete resection. Adjuvant therapy was used variably, and its use increased with patient age. Forty‐eight percent of patients received the combination of surgery, radiation, and chemotherapy, and 4% did not receive any treatment. As expected, patients ≤5 years of age had better 5‐year survival than those ages 6–10 (P = 0.01) or 11–19 years (P = 0.0077). Other factors associated with poor survival included black race and central tumor location. Better outcomes were associated with treatment that included surgery, radiotherapy, and chemotherapy compared to any other treatment combinations. Radiotherapy had no impact on survival in the 0 to 10‐year‐old age group, but was associated with improved survival for patients 11–19 years. We report an extensive demographic and survival analysis of pediatric glioblastoma. The observed differences likely reflect variances in tumor biology and likelihood of treatment receipt. Improved survival was associated with the use of surgery, radiotherapy, and chemotherapy. Radiation therapy was not associated with survival in patients younger than 10 years of age.

Primary leiomyosarcoma in the colon: A case report

RATIONALE

Leiomyosarcoma (LMS) is a common type of soft tissue sarcoma. Primary colonic LMS in general is a very rare entity, accounting for 1% to 2% of gastrointestinal malignancies.

PATIENT CONCERNS

We report a case of 55-year-old female who presented with a sudden onset of sharp right lower quadrant abdominal pain. Electronic colonoscopy showed a normal lumen. However, an abdominal computed tomography scan revealed a mass of soft tissue attenuation inseparable from the ascending colon which appeared as a gastrointestinal stromal tumor (GIST).

DIAGNOSES

It is important to diagnose LMS definitively by immunohistochemical profiling of smooth muscle actin, desmin, and CD34.

INTERVENTIONS

She underwent laparotomy and right hemicolectomy, and histology confirmed a colonic LMS. The patient received no oncological treatment after surgery.

OUTCOMES

No recurrence or metastasis was observed at 5 months postoperatively. It is crucial to identify colonic LMS precisely based on immunohistochemistry, and thereby distinguish it from GIST.

LESSONS

Further investigation on LMS cases so far is required to establish standard treatment strategies.