Clinicopathological features of primary leiomyosarcoma of the gastrointestinal tract following recognition of gastrointestinal stromal tumours

Colorectal Leiomyosarcoma: Demographics Patterns, Treatment Characteristics, and Survival Analysis in the U.S. Population

BACKGROUND

Colorectal leiomyosarcoma (CR-LMS) is a rare neoplasm arising from smooth muscle cells. It accounts for less than 0.1% of all colorectal malignancies. In this population-based study, we aim to understand the demographics, treatment characteristics, and pathologic factors associated with survival in CR-LMS.

METHODS

Data from the SEER Program (2000-2018) were analyzed using SEER*Stat and SPSS. Statistical methods included descriptive analysis, Kaplan-Meier survival curves, log-rank tests, and Cox proportional hazards regression to assess the impact of various factors on disease-specific and overall survival.

RESULTS

A total of 191 cases of CR-LMS were identified. Most patients were 60-69 years of age (median: 64 years) and Caucasian (78%). There was nearly the same distribution in sex (M:F ratio; 1:1.2). The overall 5-year observed survival was 50.3% (95% C.I., 46.3-54.2). The 5-year disease-specific survival (DSS) was 66.1% (95% C.I., 62.0-70.1). The 5-year overall survival after resection was 60.8% (95% C.I., 56.3-65.3). Multivariable analysis identified grades III and IV (p = 0.028) as negative predictors of overall survival. Regional spread and distant stage are negative predictors of overall survival (p < 0.01).

CONCLUSION

Our data reveals that colorectal leiomyosarcoma (CR-LMS) often presents in patients around 64 years old with advanced stages and poor differentiation. Key adverse prognostic factors include older age, high tumor grade, large tumor size, and distant metastases, with surgical resection showing the best survival outcomes. To improve outcomes, further research and consolidation of data are essential for developing targeted therapies and comprehensive guidelines.

Statistics of Visceral Sarcoma in Japan: Report From the Population-Based National Cancer Registry (NCR) in Japan

BACKGROUND AND OBJECTIVES

Sarcomas developing in the visceral organs are extremely rare, with no previous reports to describe their national epidemiology. We analyzed Japanese domestic statistics for visceral sarcoma, using the National Cancer Registry (NCR) in Japan, a population-based database launched in 2016.

METHODS

We identified 3245 cases of visceral sarcomas in the NCR dated 2016-2019 to analyze demographic and disease information, initial diagnostic process, volume and type of the hospitals, treatment, and prognosis.

RESULTS

Visceral sarcoma shows a higher prevalence in the older generation (60+ years), with a significant male predominance (p = 0.006). Leiomyosarcomas occurred frequently in the gastrointestinal tract (N = 240; 39.5%), and angiosarcomas in the liver, gall bladder, pancreas, and spleen (N = 244; 43.9%). Visceral sarcomas were often treated in facilities of lower volume without specific adjuvant treatments (p < 0.001). The cumulative 3-year overall survival was 44.8%, and several factors such as surgery or absence of chemotherapy positively affected survival.

CONCLUSIONS

This is the first nationwide study in Japan to analyze the inclusive epidemiology of visceral sarcomas. Visceral sarcomas are characterized by senior and male predominance with relatively poor prognosis, often managed in nonspecialized facilities and rarely with adjuvant therapies. Several histologic subtypes had the propensity to develop in specific organs.

Leiomyosarcoma of the abdomen and retroperitoneum; a systematic review

Background

Intraabdominal and retroperitoneal leiomyosarcomas are rare cancers, which cause significant morbidity and mortality. Symptoms, treatment and follow up differs from other cancers, and proper diagnosis and treatment of intraabdominal and retroperitoneal leiomyosarcomas is of utmost importance. We performed a systematic review to collect and summarize available evidence for diagnosis and treatment for these tumours.

Methods

We performed a systematic literature search of Pubmed from the earliest entry possible, until January 2021. Our search phrase was (((((colon) OR (rectum)) OR (intestine)) OR (abdomen)) OR (retroperitoneum)) AND (leiomyosarcoma). All hits were evaluated by two of the authors.

Results

Our predefined search identified 1983 hits, we selected 218 hits and retrieved full-text copies of these. 144 studies were included in the review.

Discussion

This review summarizes the current knowledge and evidence on non-uterine abdominal and retroperitoneal leiomyosarcomas. The review has revealed a lack of high-quality evidence, and randomized clinical trials. There is a great need for more substantial and high-quality research in the area of leiomyosarcomas of the abdomen and retroperitoneum.

Systematic Review Registration

PROSPERO, identifier, CRD42023480527.

Diagnostic and therapy of an early-stage primary leiomyosarcoma of the sigmoid colon: A case report

Key Clinical Message

Primary leiomyosarcoma of the colon is a very rare tumor entity. Because of unspecific findings, diagnostic can be challenging. Most cases are diagnosed in advanced stages with poor overall survival. Unclear histological findings of smooth muscle cell tissue in colon biopsies together with a tumor of the colon wall in computed tomography (CT) imaging should lead to the differential diagnosis of primary colonic leiomyosarcoma and further diagnostic procedures.

Abstract

Primary colonic leiomyosarcoma is an extremely rare tumor entity arising from smooth muscle cells in the colon wall. Only 0.1% of all colorectal malignancies are leiomyosarcomas. Most patients are diagnosed in advanced disease stages. The overall survival rates are low, and recurrence rates are high. Only few data regarding the outcome in localized early disease stages are available. We report the case of an early-stage primary leiomyosarcoma of the sigmoid colon treated with surgical resection. We present the case of a 53-year-old male patient who underwent a colonoscopy due to intermittent rectal bleeding. Colonoscopy revealed an intraluminal polypoid growing tumor in the sigmoid colon. A biopsy was performed with inconclusive histological results. A CT scan revealed a process in the sigmoid colon with wall thickening; there was no evidence of metastatic lesions. After laparoscopic oncological resection of the sigmoid colon, histological examination surprisingly revealed a localized high-grade leiomyosarcoma. Primary leiomyosarcoma of the colon is a rare tumor entity and diagnostic can be challenging. Only a few patients with colonic leiomyosarcoma diagnosed in localized early disease stages and treated with complete surgical resection have been reported in the literature. These patients seem to have a better prognosis with longer overall survival. Because of unspecific diagnostic findings and the lack of symptoms in early disease stages, interdisciplinary collaborations between gastroenterologists, radiologists, pathologists, and surgeons are crucial for early diagnosis and treatment.

A rare case of leiomyosarcoma with a pleomorphic component of the sigmoid colon

A 66-year-old man presented to our institution with a positive fecal occult blood test and lower abdominal pain. Although a tumor was found in the sigmoid colon, biopsy and imaging studies failed to enable the diagnosis of the cancer, and the patient underwent surgery for treatment and diagnosis. The tumor had two distinct areas with differing features shown both histopathologically and on imaging; it was thus diagnosed as a leiomyosarcoma of the sigmoid colon with a pleomorphic component. Here, we describe a rare case of leiomyosarcoma of the sigmoid colon with a pleomorphic component. There are no reports of leiomyosarcoma with pleomorphic components arising in the colon in the literature; thus, the recurrence and metastatic characteristics are unknown. Therefore, accumulating cases in the literature may provide valuable insights into diagnosing and treating these rare tumors.

Gastric Leiomyosarcoma in Post-Gastrointestinal Stromal Tumor Era: Revisit

Primary gastric leiomyosarcoma is an exceptionally rare disease. This review covers 41 post-gastrointestinal stromal tumor (GIST) era gastric leiomyosarcoma cases that are supported by immunohistochemistry markers. Other spindle cell lesions are also excluded through histological and immunohistochemistry evaluations. The patients range from 3 to 82 years old, with an average age of 54.6 years. The male-to-female ratio is 1.4:1, from diverse geographic areas. Patients may experience abdominal symptoms, and tumor sizes vary between 1 cm and 22 cm. Morphologically, tumors originate from the muscularis propria or the muscularis mucosae, well-circumscribed with spindle cells arranged in fascicule. Tumoral cells exhibit positivity for smooth muscle markers while being negative for GIST markers and others. The mitotic index ranges from 2 to 500/50 high power field. Ki-67 index varies from 15% to 70%. Management typically involves gastrectomy and other appropriate treatments, with tumor recurrence being uncommon. 56% of patients are alive, with 5 patients dying from this disease. Statistical analyses conducted on post-GIST era cases reveal that a mitotic index of ≥100/50 high power field, tumor recurrence, metastasis, or positive lymph nodes significantly correlate with prognosis.

Current landscape of primary small bowel leiomyosarcoma: cases report and a decade of insights

The incidence of leiomyosarcoma (LMS) is about 4-5/100,000 individuals per year. LMSs occurring in the small bowel are even rarer, and their preoperative diagnosis is very difficult. We described two patients with pathologically confirmed small bowel LMS and analyzed their clinical and medical imaging features. Similar cases reported in English in Pubmed database over the past decade were reviewed and summarized. These tumors were categorized by the growth direction and relationship with the intestinal lumen into three types: intraluminal (n = 10), intermural (n = 3), and extraluminal (n = 7). Notably, among the three types of LMS, the intramural leiomyosarcoma stands out as a noteworthy subtype. Emerging evidence suggests that smaller tumor size (< 5 cm) and the intraluminal type may serve as favorable prognostic indicators, while the extraluminal type is associated with relatively poor prognosis. Furthermore, the integration of imaging features with CA125 and LDH biomarkers holds promise for potential diagnostic value in LMS.

Non-gastrointestinal stromal tumor, mesenchymal neoplasms of the gastrointestinal tract: a review of tumor genetics, pathology, and cross-sectional imaging findings

There is a diverse group of non-gastrointestinal stromal tumor (GIST), mesenchymal neoplasms of the gastrointestinal (GI) tract that demonstrate characteristic pathology and histogenesis as well as variable imaging findings and biological behavior. Recent advancements in tumor genetics have unveiled specific abnormalities associated with certain tumors, influencing their molecular pathogenesis, biology, response to treatment, and prognosis. Notably, giant fibrovascular polyps of the esophagus, identified through MDM2 gene amplifications, are now classified as liposarcomas. Some tumors exhibit distinctive patterns of disease distribution. Glomus tumors and plexiform fibromyxomas exhibit a pronounced affinity for the gastric antrum. In contrast, smooth muscle tumors within the GI tract are predominantly found in the esophagus and colorectum, surpassing the incidence of GISTs in these locations. Surgical resection suffices for symptomatic benign tumors; multimodality treatment may be necessary for frank sarcomas. This article aims to elucidate the cross-sectional imaging findings associated with a wide spectrum of these tumors, providing insights that align with their histopathological features.

Leiomyosarcoma of the rectum: A systematic review of recent literature

Leiomyosarcomas (LMSs) are rare tumors originating from the muscular layer. We performed a literature review of cases of confirmed rectal leiomyosarcomas (rLMSs) to clarify the history of such an infrequent tumor arising at such an uncommon location. In this research local recurrence was related to poorly differentiated rLMS and no other association between recurrence and any criteria was found. Concerning overall survival (OS), rLMS patients developing recurrence presented shorter longevity compared with the group without.

Primary Gastric Leiomyosarcoma: A Rare Case

Gastric leiomyosarcoma is extremely rare. In this paper, we present a case of primary gastric leiomyosarcoma located in the fundus/cardia region. The tumoral spindle cells show diffusely moderate nuclear atypia, with focally marked atypia and rare mitotic figures. Additionally, the tumoral cells exhibit positive immunoreactivity to smooth muscle actin and desmin while testing negative for CD117 (c-kit). The tumor was successfully resected through a laparoscopic partial gastrectomy, and the patient experienced a full recovery. There has been no recurrence or metastatic tumor detection during the seven-year follow-up period. Furthermore, we conducted a literature review on primary gastric leiomyosarcoma.

The Landscape of Primary Gastric Leiomyosarcoma in Texas Population: Analysis of Texas Cancer Registry Data

Introduction Primary gastric leiomyosarcoma is an extremely rare disease. There have been no previous studies regarding gastric leiomyosarcoma in the Texas population. Methods Anonymous data of gastric leiomyosarcoma from the Texas Cancer Registry (TCR) was used. Information collected included the primary tumor site, age at diagnosis, gender, race/ethnicity, diagnosis and treatments, tumor size, lymph node and metastasis status, grade and stage, body weight and height, public health regions and payer, metropolitan status, neighborhood poverty level, smoking status, survival interval, and cause of death for statistical analysis. Result Thirty-three cases from 2003-2019 were selected. Primary gastric leiomyosarcoma was more commonly diagnosed in patients over 50 years of age, females, and individuals of white race. The diagnosis was primarily based on histology, and the disease was typically treated with surgery and chemotherapy. At the time of diagnosis, 45.5% of patients were in the late stage, and 48.5% of patients died from gastric leiomyosarcoma with a mean survival interval of 15.3 months. BMI scores showed a positive correlation with survival intervals. Surveillance, Epidemiology and End Results (SEER) tumor staging was associated with the prognosis of gastric leiomyosarcoma. Conclusion There were multiple disparities among patients with primary gastric leiomyosarcoma in the Texas population. The SEER summary stage was associated with the prognosis of gastric leiomyosarcoma.

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.

Rectal leiomyosarcoma as the initial phenotypic manifestation of Li-Fraumeni-like syndrome: a case report and review of the literature

BACKGROUND

Leiomyosarcoma is a rare malignant tumor of smooth muscle origin and represents 10-20% of all soft tissue sarcomas. Primary colon and rectal sarcomas constitute < 0.1% of all large bowel malignancies. In Li-Fraumeni syndrome, sarcomas are the second most frequent cancer (25%). Li-Fraumeni syndrome is a genetic disease with a familial predisposition to multiple malignant neoplasms. This syndrome has an autosomal dominant pattern of inheritance and high penetrance characterized by germline TP53 mutations. Patients with a history of cancer who do not meet all the "classic" criteria for Li-Fraumeni syndrome are considered to have Li-Fraumeni-like syndrome. To the best of our knowledge, this article is the first report of a patient with rectal leiomyosarcoma as the initial phenotypic manifestation of Li-Fraumeni-like syndrome. The authors also present a literature review.

CASE PRESENTATION

A 67-year-old Brazilian woman underwent anterior rectosigmoidectomy and panhysterectomy secondary to rectal leiomyosarcoma. She subsequently developed carcinomatosis and died 2 years after the operation. Her family medical history consisted of a daughter who died at 32 years of age from breast cancer, a granddaughter diagnosed with adrenocortical carcinoma at 6 years of age and two siblings who died from prostate cancer. A genetic study was carried out to identify a pathogenic variant of Li-Fraumeni syndrome. In the DNA extracted from the peripheral blood leukocyte, restriction fragment length polymorphism was analyzed to search for mutations in the TP53 gene. The DNA sequencing identified the germline pathogenic variant p. R337H heterozygous in exon 10 of TP53. The patient was classified as having Li-Fraumeni-like syndrome.

CONCLUSION

In patients with rectal leiomyosarcoma, it is advisable to investigate the family history of cancer and perform genetic studies to screen for Li-Fraumeni syndrome.

Totally laparoscopic resection using delta-shaped anastomosis of jejunal leiomyosarcoma with intussusception at the angle of Treitz: a case report

Background

A leiomyosarcoma of the gastrointestinal tract is extremely rare. We report a case of jejunal leiomyosarcoma with intestinal intussusception at the angle of Treitz that was successfully treated with laparoscopic resection followed by intracorporeal reconstruction using a delta-shaped anastomosis.

Case presentation

A 54-year-old man was referred to our hospital due to fatigue and loss of appetite. Blood tests showed anemia. Enteroscopy and subsequent enterography using meglumine sodium amidotrizoate showed easily hemorrhagic tumor (10 cm in diameter) in the jejunum just beyond the angle of Treitz. Contrast-enhanced computed tomography revealed jejunojejunal intussusception. Histopathological examination of a biopsy specimen revealed a leiomyosarcoma. Laparoscopic resection of the tumor without reduction of the intussusception was performed. The resected line of the proximal intestine was very close to the ligament of Treitz in the present case. Intracorporeal jejunojejunostomy was completed using a delta-shaped anastomosis, wherein anastomosis was performed between the posterior walls of the proximal and distal jejunums after minimal mobilization around the ligament of Treitz. The patient’s postoperative course was uneventful, and he was discharged at 10 days postoperatively. No recurrence has been observed within 2 years after surgery.

Conclusions

We present a case in which a totally laparoscopic surgery for leiomyosarcoma located at the angle of Treitz with jejunojejunal intussusception was performed successfully.

Mesenchymal tumors of the stomach: radiologic and pathologic correlation

Mesenchymal tumors of the stomach are uncommon, with gastrointestinal stromal tumor (GIST) being the most common among them. Majority of the tumors may arise from cells of Cajal, smooth muscle cells, neural cells, totipotent stem cells, adipocytes or fibroblasts. Imaging plays an important role not only in staging but also in characterizing these tumors. Many of these tumors have characteristic imaging features. GISTs usually present as large cavitating and necrotic tumors with exophytic component. Presence of fat tissue within the tumor suggests a lipoma or a teratoma, early phase hyperenhancement indicates glomus tumor and hemangioma, and delayed contrast enhancement is seen in schwannoma. Their differentiation from epithelial tumors like carcinoma and neuroendocrine tumors is often possible based on the location (mesenchymal tumors are intramural), spread, morphological appearance and enhancement patterns. However, overlapping features exist between these tumors with imaging often being only suggestive. A biopsy is necessary for a definitive diagnosis in many cases.

Correlation between pneumo-computed tomography and pathology findings for subepithelial gastric lesions

OBJECTIVE

This article aims to show the usefulness of the pneumo-computed tomography gastric distention technique in the detection and morphological characterization of subepithelial gastric lesions. We correlate the pneumo-computed tomography and pathology findings in lesions studied at our institution and review the relevant literature.

CONCLUSION

Pneumo-computed tomography, combined with multiplanar reconstructions, three-dimensional reconstructions, and virtual endoscopy, is useful for delineating the morphological details of subepithelial gastric lesions, thanks to the additional gastric distention. This technique better delimits and characterizes the upper and lower margins of the lesions. Pneumo-computed tomography can be considered a useful noninvasive imaging techniques for characterizing these lesions.

Primary duodenal dedifferentiated liposarcoma: A case report and literature review

BACKGROUND

Dedifferentiated liposarcoma (DDLPS) is an extremely rare neoplasm that exhibits various morphologies. The tumor is characterized by immunoreactivity to MDM2 and CDK4 and can be confirmed by detecting MDM2 amplification via fluorescence in situ hybridization (FISH). Herein, we report an unusual case of DDLPS arising from the duodenum.

CASE SUMMARY

A 64-year-old man presented with repeated abdominal pain and weight loss. Radiologic studies revealed a mass of the duodenum involving the pancreas. The patient was treated with pylorus-preserving pancreaticoduodenectomy. Histologically, the tumor showed a high-grade sarcoma. Immunohistochemistry demonstrated that the tumor cells were positive for MDM2 and CDK4 expression. MDM2 amplification was detected via FISH, leading to the final diagnosis of DDLPS. Following surgery, the patient was treated in the intensive care unit due to peritonitis, and died 60 d after surgery.

CONCLUSION

To the best of the authors’ knowledge, this is the first case of primary duodenal DDLPS in Korea and the third case in the English-language literature. Care must be taken not to misdiagnose DDLPS as another high-grade tumor. Liposarcoma should be in the differential diagnosis list.

Clinical and Molecular Characteristics of Rare Malignant Tumors of Colon and Rectum

Simple Summary

Tumors of colon and rectum other than adenocarcinomas represent a neglected issue from clinical and laboratory points of view because of their rarity. In this review, we summarize and describe the rare histologic entities occurring in colon and rectum. Clinical and pathologic characteristics, prognostic behavior, treatments, and altered genes are reported to provide readers with a paramount and comparative perspective. In relation to this, we propose that improvements in registries and multidisciplinary research are warranted to ameliorate their management.

Abstract

The most frequent form of colorectal cancer is represented by adenocarcinoma being about 98% of tumor histological types. However, other rare histotypes can be found in colon and rectum (adenosquamous, goblet cell adenocarcinoma, lymphoma, medullary carcinoma, melanoma, mesenchymal, neuroendocrine, plasmacytoma, signet ring, squamous tumors). Altogether, these forms account for less than 2% of colorectal tumors. There are no specific diagnostic or therapeutic recommended approaches and most of the information available from literature derives from small and retrospective clinical series. In the present study, we provide a paramount and updated view on clinical and biologic characteristics of rare colorectal tumors.

Prognostic Factors in Gastrointestinal Leiomyosarcomas: An Analysis Using the Surveillance, Epidemiology, and End Results (SEER) Database

Background Gastrointestinal leiomyosarcomas (LMSs) from intramural smooth muscle are extremely rare, with limited literature. This paper evaluates the epidemiology and survival and prognostic factors in LMSs of the gastrointestinal tract. Methods Clinical data from the Surveillance, Epidemiology and End Results (SEER) 18 registry from 2001 to 2016 with additional treatment fields were compared between primary tumor sites using the chi-squared test for categorical variables and ANOVA for continuous variables. A five-year survival rate analysis was performed for overall and cancer-specific survival. Hazard ratios (HRs) were calculated using univariate and multivariate Cox proportional models using the variables age group, tumor location, grade, stage, surgery, and chemotherapy. Results We identified a total of 523 patients diagnosed with LMSs of the gastrointestinal tract. The median age of diagnosis was 66 years, with no significant difference between tumor sites for age, sex, and race. The five-year overall survival was 77.3%, and the cancer-specific survival was 90.3%. In the multivariate analysis, grade and stage of tumor were the only factors significantly affecting survival in this cohort. Conclusion While surgical status significantly affected survival in the univariate analysis, when adjusted for other factors, the HR for death was not significantly different by surgical therapy. Grade 3 tumors and tumors with distant metastasis at diagnosis were associated with worse survival among these patients.

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.

Two cases of primary leiomyosarcoma of sigmoid colon treated with laparoscopic surgery: A case report and a review of literature

INTRODUCTION AND IMPORTANCE

Leiomyosarcoma (LMS) of the colon is an extremely rare and highly invasive tumor arising from the muscularis propria of the gastrointestinal tract. After the introduction of oncogenic role of KIT by immunohistochemistry (IHC), the reported cases of gastrointestinal leiomyosarcoma were highly limited. True LMS of the colon is such a rare disorder that there isn't much description of its nature.

CASE PRESENTATION

We reported two very rare cases of primary leiomyosarcoma of sigmoid colon, which referred to our institution with symptoms of abdominal pain, lower GI bleeding and fatigue. After the initial investigations, both patients were diagnosed with primary LMS of sigmoid colon that underwent laparoscopic tumor resection.

CLINICAL DISCUSSION

The classical colonic LMS presents with a vast majority of non-specific symptoms including mild abdominal pain, fresh/obscure rectal bleeding, and weight loss. The most common location for colonic LMS is the sigmoid colon, and ascending colon. The prognostic factors for the disease outcome have not been established properly; however, patient age, tumor size/grade, and local/distant dissemination are of great importance.

CONCLUSION

Herein, we reported two rare cases of primary leiomyosarcoma of sigmoid colon that was treated with laparoscopic surgery.

Gastric mesenchymal tumor with smooth muscle differentiation and echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion

Gastric mesenchymal tumors are relatively rare, and their molecular pathogeneses are poorly understood, except for gastrointestinal stromal tumor, desmoid, and inflammatory myofibroblastic tumors. We report a case of a gastric mesenchymal tumor with prominent smooth muscle cell differentiation and an echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion. On gross section, the tumor was 26 mm at the largest diameter, well-circumscribed, and located in the submucosal and muscular layers of the stomach wall. Histologically, the tumor comprised intersecting fascicles of spindle cells, non-atypical nuclei, and highly eosinophilic cytoplasm. Myxoid changes were observed focally, but inflammatory infiltrates were only evident in limited areas. Immunochemical staining revealed that the tumor was positive for α-smooth muscle actin and desmin. Diffuse positive staining for h-caldesmon was observed throughout the tumor, which suggested smooth muscle cell differentiation. Intracytoplasmic staining for ALK protein was also observed, and fluorescence in situ hybridization using ALK break-apart probes showed split chromosomal signals. RNA-sequencing analysis identified EML4-ALK fusion transcripts. We concluded that the tumor was a gastric mesenchymal tumor with smooth muscle differentiation based on its distinct differential smooth muscle properties, such as highly eosinophilic cytoplasm and diffuse expression of h-caldesmon. Furthermore, activated ALK may underly the tumor's pathogenesis.

Laparoscopic and endoscopic cooperative surgery for leiomyosarcoma of the stomach: a case report with a review of the literature

Background

Leiomyosarcoma is a rare tumor that could originate from the gastrointestinal tract, uterus, kidney, retroperitoneum, and the soft tissues of the extremities. It accounts for only 1% of all gastrointestinal mesenchymal tumors and primary leiomyosarcoma of the stomach is extremely rare. Most cases reported as leiomyosarcoma of the stomach before the development of KIT immunohistochemistry might be gastrointestinal stromal tumors (GISTs) of the stomach and only 18 cases of leiomyosarcoma of the stomach have been reported since early 2000s. We report here a patient with leiomyosarcoma of the stomach treated by laparoscopic and endoscopic cooperative surgery (LECS).

Case presentation

A 59-year-old man was referred to our hospital for an early gastric cancer, which was initially treated by endoscopic submucosal dissection. Six months after his initial treatment, a follow-up esophagogastroduodenoscopy revealed a small polypoid lesion at the lesser curvature of the proximal stomach, which appeared to be a hyperplastic polyp. However, one and a half years later, the lesion grew and showed more irregular surface. Biopsy at the time revealed smooth muscle cell proliferation suggestive of leiomyoma. Three years later, the lesion grew even larger and biopsy showed pleomorphic spindle cells. Immunohistochemical study showed positive staining for alpha-smooth muscle actin and desmin, but negative for c-kit and CD34. Ki-67 labeling index was nearly 60%. Based on these findings, the diagnosis of leiomyosarcoma was established. The patient subsequently underwent a partial gastrectomy by LECS. The patient is currently in good condition without recurrence or metastasis at 12 months after surgery.

Conclusions

Leiomyosarcoma of the stomach is extremely rare. This is the first report of leiomyosarcoma of the stomach treated by LECS. We could also follow its appearance change through endoscopic examination for 3 years.

Mesenchymal tumours of the gastrointestinal tract

Mesenchymal tumours represent a heterogenous group of neoplasms encopassing benign, intermediate malignancy, and malignant entities. Sarcomas account for approximately 1% of human malignancies. In consideration of their rarity as well as of intrinsic complexity, diagnostic accuracy represents a major challenge. Traditionally, mesenchymal tumours are regarded as lesions the occurrence of which is mostly limited to somatic soft tissues. However, the occurrence of soft tissue tumours at visceral sites represent a well recognized event, and the GI-tract ranks among the most frequently involved visceral location. There exist entities such as gastrointestinal stromal tumours (GIST) and malignant gastointestinal neuroectodermal tumors that exhibit exquisite tropism for the GI-tract. This review will focus also on other relevant clinico-pathologic entities in which occurrence at visceral location is not at all negligible.

The Clinico-histopathological Spectrum of Tumors and Tumor-Like Lesions in Adult Intussusception

BACKGROUND

Intussusception is an uncommon cause of intestinal obstruction in adults. The etiology of this disease differs from the children. Thus, its management depends on the possible etiology and is different from pediatric cases.

AIMS

We aimed to study the clinico-histopathological spectrum of the tumors and tumor-like lesions in the intussusception in adults.

MATERIAL AND METHODS

A retrospective review of the adult (> 18 years) intussusception cases was performed. The clinical data and follow-up were obtained. The histopathology was reviewed along with the special stains and immunohistochemistry for ascertaining a histopathological diagnosis.

RESULTS

Fifteen cases of adult intussusception were identified from 107 resected specimens of adult intestinal obstruction. The mean age was 44.5 years with a male/female ratio of 1.1:1. A definitive pathology could be ascertained in 80% of the cases (n = 12/15). Eight cases had benign non-neoplastic etiology (53.3%) (33.3% tumor-like lesions) while seven cases (46.7%) had neoplastic etiology (20% benign neoplastic; 26.7% malignant neoplastic). All cases of colonic or enterocolic intussusceptions were associated with neoplasia whereas 90% of the enteric intussusceptions occurred due to benign non-neoplastic causes.  CONCLUSIONS: Non-neoplastic causes are predominant in the enteric intussusceptions while neoplastic causes are more commonly associated with colonic or enterocolic intussusceptions. The post-operative histopathological examination concludes on the adequacy of the index surgery or the provision of further management if required.

Leiomyosarcoma of the small intestine presenting as abdominal myofascial pain syndrome (AMPS): case report

OBJECTIVE

To highlight an extremely unusual presentation of an aggressive, rare small bowel malignancy presenting as abdominal myofascial pain syndrome.

CASE PRESENTATION

The report is presented from a tertiary pain medicine unit at a university teaching hospital. A female patient presenting with chronic abdominal pain was initially diagnosed as abdominal myofascial pain syndrome. The report details the possible facilitation of the diagnosis of a rare, highly aggressive small bowel tumour by interventional treatment for abdominal myofascial pain syndrome.

CONCLUSION

This case highlights a rare and aggressive malignancy of the small intestine presenting clinically as abdominal myofascial pain syndrome.

Leiomyosarcoma of the transverse colon with lymph node metastasis and malignant transformation: a case report

Background

The concept of GIST was established in 1998, clearly differentiating between gastrointestinal leiomyosarcoma and GISTs among gastrointestinal mesenchymal tumors. Lymph node metastasis is extremely rare in true gastrointestinal leiomyosarcoma, and there are no reports of malignant transformation from leiomyoma.

Case presentation

The patient was an old woman who had undergone endoscopic mucosal resection for an Is polyp on the left side of the transverse colon at the age of 73. She was diagnosed with leiomyoma with positive surgical margins. Subsequently, she presented to our institution with a sensation of pressure in the upper abdominal region as a chief complaint at the age of 76 years. Abdominal computed tomography and colorectal endoscopy showed a tumor lesion with invagination of the intestines in the transverse colon, the same site as that of the previously resected leiomyoma. A biopsy suggested a smooth muscle tumor, and we performed partial left transverse colectomy and lymph node dissection under a diagnosis of recurrence and enlargement of the previously incompletely resected leiomyoma. Histopathological examination revealed spindle-shaped tumor cells, and the mitotic activity was 30–40/10 high-power field. Tumor cells were immunohistologically positive for α-smooth muscle actin and h-caldesmon; partially positive for desmin; negative for c-kit, CD34, DOG-1, and the S-100 protein; and showed a Ki-67 labeling index of 70–80%. She was diagnosed with leiomyosarcoma malignantly transformed from leiomyoma. Metastasis was found in 1 of the 14 resected lymph nodes. The patient did not undergo adjuvant chemotherapy, but has survived with no recurrence at 2 years after the surgery.

Conclusions

We have reported a case of leiomyosarcoma of the transverse colon with lymph node metastasis that was malignantly transformed from a leiomyoma.

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

Introduction: Primary leiomyosarcoma (LMS) of the colon is a rare and aggressive gastrointestinal tract tumor, associated with poor prognosis.Case presentation and methods: We present the case of an asymptomatic patient who was diagnosed with a low sigmoidal stricture on routine colonoscopy. Although biopsies were inconclusive, an oncological partial mesorectal excision (PME) was performed due to the malignant macroscopic aspect. Pathological examination surprisingly revealed a LMS. The patient received no adjuvant chemo- or radiotherapy, but is seen on regular follow-up. We review the literature on leiomyosarcoma of the colon: its diagnosis, treatment, and prognosis.Results: Up until now the patient shows no sign of recurrence, 15 months postoperatively.Conclusion: Radical resection is the treatment of choice for primary leiomyosarcoma of the colon and long-term follow-up is needed to evaluate metastatic disease or local recurrence.

Smooth muscle tumors of the gastrointestinal tract: an analysis of prognostic features in 407 cases

Smooth muscle tumors represent the second most common mural mesenchymal neoplasm in the gastrointestinal tract, but established criteria for prognostic assessment of these tumors are lacking. A large cohort of surgically resected intramural gastrointestinal smooth muscle tumors from 31 institutions was analyzed to identify potential prognostic features. Pathologic features were assessed by expert gastrointestinal and/or soft tissue pathologists at each center. Immunohistochemical confirmation was required. A total of 407 cases from the esophagus (n = 97, 24%), stomach (n = 180, 44%), small bowel (n = 74, 18%), and colorectum (n = 56, 14%) were identified. Patients ranged in age from 19 to 92 years (mean 55 years), with a slight female predominance (57%). Mean tumor size was 5.4 cm, with the largest tumor measuring 29 cm. Disease progression following surgery, defined as local recurrence, metastasis, or disease-related death, occurred in 56 patients (14%). Colorectal tumors were most likely to progress, followed by small bowel and gastric tumors. None of the esophageal tumors in this series progressed. Receiver operator characteristic analysis identified optimal cutoffs of 9.8 cm and 3 mitoses/5 mm² for discriminating between progressive and non-progressive tumors. Histologic features strongly associated with progression by univariate analysis included moderate-to-severe atypia, high cellularity, abnormal differentiation (defined as differentiation not closely resembling that of normal smooth muscle), tumor necrosis, mucosal ulceration, lamina propria involvement, and serosal involvement (P < 0.0001 for all features). Age, sex, and margin status were not significantly associated with progression (P = 0.23, 0.82, and 0.07, respectively). A risk assessment table was created based on tumor site, size, and mitotic count, and Kaplan-Meier plots of progression-free survival for each subgroup revealed progression-based tiers. Based on our findings, it appears that nonesophageal gastrointestinal smooth muscle tumors measuring >10 cm and/or showing ≥3 mitoses/5 mm² may behave aggressively, and therefore close clinical follow-up is recommended in these cases.

Ileo-ileal intussusception caused by small bowel leiomyosarcoma: A rare case report

INTRODUCTION

Intussusception is the telescoping of one segment of the bowel into an adjacent bowel segment, causing venous congestion, edema, and blood supply reduction. We present a case of ileo-ileal intussusception in an adult patient with intestinal obstruction caused by a rare mesenchymal malignant lesion of the distal ileum: Leiomyosarcoma (LMS).

PRESENTATION OF CASE

A 90-year-old Caucasian man presented to the hospital with a two-day history of abdominal pain, nausea, and bowel occlusion. Preoperative Computer Tomography (CT) showed a solid mass with stratified walls in the lumen of the cecum with the classics "bulls-eye" appearance with concentric rings, suggestive of intussusception. The patient underwent emergency laparotomy with evidence of a small bowel wall tumor driving ileo-ileal intussusception with ischemic damage. Ileocecal resection was performed without postoperative complications. Histopathological examination showed a tumor on the muscular layer of the small bowel. The definitive diagnosis was LMS.

DISCUSSION

Adult intussusception is a rare condition, with an incidence of 2/1 000 000 cases per year worldwide. About 60% of patients suffering from this disease require surgery. Clinical presentation can be non-specific because of its no characteristic signs and symptoms. The most common presenting symptom is abdominal pain with bowel obstruction sings. Intussusception can occur anywhere along the small and large intestine and it is typically associated with a Lead Point (LP). The LP may be benign or malignant conditions. Infrequent malignant causes include LMS.

CONCLUSION

Diagnosis of intussusception is relatively challenging because of its non-specific symptoms. CT scan is the examimation of choice for the diagnosis because of its peculiar images. In adults, surgical treatment is recommended with laparoscopic or open approach according to surgeon expertise, sometimes in an emergency setting.

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.

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.

Leiomyosarcoma of the stomach: A case report

BACKGROUND

Leiomyosarcoma of the stomach is extremely rare, and only 13 cases have been reported in the literature. Before the advent of KIT immunohistochemistry, gastrointestinal stromal tumors (GISTs) were misdiagnosed as leiomyomas and leiomyosarcomas. Leiomyosarcoma rarely occurs in organs besides the uterus and is rarely located in the stomach.

CASE SUMMARY

A 57-year-old woman presented with the symptom of melena over a one-month period. She had suffered weight loss, weakness, nausea and vomiting for fifteen days. At a local hospital, computed tomography showed a very large mass in the stomach, and the results of endoscopic examination and histopathological diagnosis were unclear. She received transfusion therapy and was transferred to our hospital. Upon arrival at our hospital, the patient was anemic. She denied any family history and had no specific past history. No signs of pulmonary metastasis were found on chest radiographs. Magnetic resonance imaging and computed tomography confirmed a very large tumor in the stomach, and no visible signs of metastatic disease were found. On October 30, 2013, the patient underwent resection of the stomach tumor and did not undergo any adjuvant treatment. The margins were negative and she had an uneventful recovery and was discharged after 12 d. One year after surgery, the patient died at home, and the cause of death were gastrointestinal obstruction and malnutrition. During that time, she was treated with Chinese medicine but the effect was not ideal. Because of gastrointestinal obstruction, the patient did not receive any re-examination.

CONCLUSION

Surgical resection is the standard treatment for gastric leiomyosarcoma. The diagnosis of this tumor mainly depends on histopathological examination. This case may suggest the aggressive behavior and poor prognosis of this tumor.

The malignancy among gastric submucosal tumor

The origin and characteristics of most submucosal tumors (SMTs) cannot easily be confirmed by gastrointestinal endoscopy or other radiological examinations. Excluding GISTs, for those other gastric SMTs, most of which are deemed benign, the necessity and timing of intervention has been ignored. Thus, the malignancy of gastric SMTs still remains unknown. In order to summarize the malignancy of these gastric SMTs, we reviewed literatures and analyzed cases of gastric SMTs including heterotopic pancreas, leiomyoma, schwannoma, glomus tumor, hemangioendothelioma, granular cell tumor (GCT), lipoma, hemangiopericytoma, lymphangioma and neurofibroma. In these literatures, there are cases of malignancy among heterotopic pancreas, leiomyoma, schwannoma, glomus tumor, hemangioendothelioma and GCT. As a result, it suggests that although most of gastric SMTs are considered benign, there are still possibilities of malignancy, which requires our attention, even active intervention and long-term follow-up.

Laparoscopic surgery to treat leiomyosarcomas of the sigmoid colon:a case report and literature review

Background

Leiomyosarcomas (LMSs) of the colon are extremely rare and highly aggressive. Although treatment of gastrointestinal LMS is not standardized, surgical resection is generally performed. The fact that the tumors are usually large at the time of diagnosis may explain why no report on laparoscopic resection of a colonic LMS has appeared.

Case presentation

A 46-year-old male presented with hematochezia 1 month in duration. Abdominal examination including palpation was normal. The levels of several blood tumor markers were normal. Colonoscopy revealed a polypoid lesion approximately 30 mm in diameter in the sigmoid colon 30 cm from the anal verge. Contrast-enhanced computed tomography revealed that the tumor was 28 mm in diameter, and that no lymph node or distant metastasis was apparent. Histopathological examination of a biopsy specimen revealed spindle-shaped cells exhibiting significant nuclear atypia and a trabecular proliferation pattern upon hematoxylin-eosin staining. Immunohistochemically, the sample was positive for SMA and desmin, and negative for c-kit, DOG-1, CD34, and S-100. Furthermore, the Ki-67 index was > 50%. We thus diagnosed a leiomyosarcoma of the sigmoid colon without any metastasis. We performed laparoscopic sigmoid colectomy and regional lymphadenectomy using five trocars. After complete curative resection, a colorectal end-to-end anastomosis was created employing the double-stapling technique. All surgical margins were negative, and no lymph node metastasis was observed. The postoperative course was uneventful, and the patient was discharged 9 days after operation. No recurrence was noted to 1 year after surgery.

Conclusions

We report the first case of a colonic LMS treated via laparoscopic surgery. Although further work is necessary to assess prognosis and to develop the treatment further, laparoscopic surgery to treat small colonic LMSs may be feasible, being both minimally invasive and curative.

An estrogen receptor-positive locally aggressive smooth muscle neoplasm of the transverse colon: A case report

RATIONALE

Extrauterine leiomyomas (LMs) in women are often positive for the estrogen receptor (ER); however, almost all extrauterine leiomyosarcomas (LMSs) are negative for ER. Invasive smooth muscle neoplasms (SMNs) of the gastrointestinal tract walls are very rare and those ER statuses have not been well studied.

PATIENT CONCERNS

A 48-year-old woman presented to our hospital with a 10 years history of recurrent severe abdominal pain and diarrhea lasting about an hour, with frequency of about twice per year. She was clinically diagnosed with a submucosal tumor (SMT) of the transverse colon and underwent a partial transverse colectomy.

DIAGNOSIS

A colonoscopy revealed a 30-mm SMT in the transverse colon. A contrast abdominal computed tomography detected a 21-mm mass with significant late phase enhancement in the transverse colon and the lesion was clinically diagnosed as an SMT. Post-operative pathology confirmed a diagnosis of ER-positive locally aggressive SMN.

INTERVENTIONS

The patient underwent laparoscopic partial transverse colectomy.

OUTCOMES

The patient received no adjuvant therapy postoperatively. The patient has remained disease-free without recurrence 13 months after the surgery.

LESSONS

This is the first case of an ER-positive invasive SMN in the gastrointestinal tract. It highlights the difficulty in classifying some gastrointestinal SMNs as either LMs or LMSs and the importance of ER status in SMNs.

Coexistence of gastrointestinal stromal tumor and leiomyosarcoma of the stomach presenting as a collision tumor: A case report and review of literature

Collision tumor of the stomach is rare. We report a rare case of a gastric collision tumor consisting of gastrointestinal stromal tumors (GISTs) and leiomyosarcoma (LMS). Computed tomography scan revealed a 15 cm sized mass in the posterior wall of the body of the stomach. Gross examination of the wedge resection specimen showed the tumor located in the muscularis propria with extramural protrusion into the peritoneal cavity and the gastric cavity with geographic necrosis, hemorrhage, and mucosal ulceration. Histologically, the majority of the tumor consisted of the GIST component and the minor area in the submucosal region consisted of the LMS component. The tumor showed an abrupt transition between GIST and LMS by histologically and immunohistochemically, suggesting a collision tumor. Furthermore, the GIST components exhibited a c-kit exon 11 mutation. On the other hand, LMS component exhibited neither c-kit nor platelet-derived growth factor receptor-alpha (PDGFRA) mutation. Here we describe a case of the collision tumor consisting of GIST and LMS and its literature review.

Leiomyosarcoma of the stomach treated by endoscopic submucosal dissection

There have been no reports of primary leiomyosarcoma of the stomach treated by endoscopic submucosal dissection (ESD). We report an extremely rare case of gastric leiomyosarcoma that was successfully treated by ESD. An asymptomatic 74-year-old female underwent esophagogastroduodenoscopy for screening in December 2013. A centrally depressed submucosal tumor 10 mm in diameter was detected at the posterior wall of the upper gastric body. Follow-up esophagogastroduodenoscopy conducted 5 months later showed that the tumor diameter had increased to 15 mm. Endoscopic ultrasound revealed a hypoechoic mass located in the second to the middle of the third layer. Endoscopic ultrasound-guided fine-needle aspiration demonstrated a myogenic tumor. The tumor was completely resected by ESD without complications. Immunohistopathological diagnosis of the resected specimen was gastric leiomyosarcoma derived from the muscularis mucosae, with negative lateral and vertical margins. No local recurrence or metastasis has been detected at 36 months after ESD. This is the first report of gastric leiomyosarcoma treated by ESD in the English language literature.

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.

Primary Leiomyosarcoma of the Colon: A Report of Two Cases, Review of the Literature, and Association with Immunosuppression for IBD and Rheumatoid Arthritis

Primary leiomyosarcomas (LMS) of the colon are rare and aggressive neoplasms and have been infrequently reported in the literature. These tumors are more aggressive and have poorer prognoses than adenocarcinoma of the colon and are often mistaken as such on initial evaluation. While the former has a clear association with inflammatory bowel disease (IBD), this correlation is not known to exist with LMS and IBD. Nor is there a known link between LMS and the immunosuppression for IBD, despite the known association between malignancy and immunosuppression for other diseases. Due to the low prevalence of this disease entity, there is limited knowledge and literature on the approach to diagnosing and treating these neoplasms, especially in the setting of the aforementioned comorbidities. Here, we describe two cases of this rare entity, presenting in two different circumstances: one in the setting of immunosuppression for IBD and arthritis, with a synchronous urothelial carcinoma, and the second appearing as the source of an acute abdomen. Both diagnoses were established following pathologic analysis.

Giant leiomyosarcoma of the rectum with lymph node metastasis: A case report and review of the literature

INTRODUCTION

Leiomyosarcoma of the gastrointestinal tract is very rare, with a reported frequency of less than 0.1% of all malignancies of the colorectum. It is important to diagnose leiomyosarcoma definitively by immunohistochemical profiling of smooth muscle actin, desmin, and CD34. True leiomyosarcoma of the colorectum diagnosed by immunnohistochemical profiling is extremely rare that only 13 reports have been published in reviews of resected gastrointestinal mesenchymal tumors after 1998. In addition, lymph node involvement is rare in patients with leiomyosarcoma. Herein we report an aggressive case of LMS in a rectosigmoid lesion with lymph node metastasis.

CASE PRESENTATION

A 76-year-old woman visited our hospital complaining of intermittent anal bleeding that had lasted 5 months. Image studies aiming at examining the cause of her anal bleeding revealed a tumor located between the right ovary, uterus, and the rectosigmoid. Histopathology of biopsied materials from the colonoscopy suggested a malignant tumor of mesenchymal origin. Surgical resection was performed with curative intent. The tumor was diagnosed as leiomyosarcoma by pathological examination. Moreover, one of the 31 regional lymph nodes retrieved was metastasized by leiomyosarcoma. Eight months later, follow-up CT scans revealed multiple recurrent lesions in the liver and peritoneum. Despite systematic chemotherapy, she deceased 12 months after the surgery.

CONCLUSION

It is crucial to diagnose leioyosarcoma precisely based on immunohistochemistry, and thereby distinguish it from GIST. Although lymph node metastasis is rare, lymphadenectomy appears to be important for high-risk LMSs to perform R0 resection. Further investigation on leiomyosarcoma cases so far is required to establish standard treatment strategies.

Cytohistological and immunohistochemical characteristics of spindle-shaped mesenchymal neoplasms occurring in the gastrointestinal tract

The purpose of the present review is to analyze the cytohistological and immunohistochemical characteristics of spindle-shaped mesenchymal gastrointestinal neoplams (MGNs), a group of unusual neoplastic conditions with different biological behavior. These tumors exhibit clinical pictures strictly related to the site of origin and dimensions, even if they appear generally with an intramural localization. This latter point may suggest an useful application of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), mainly followed by the cell-block procedure (CBP) in the differential diagnostic approach. First of all, we discuss the most common entity of MGNs represented by gastrointestinal stromal tumors (GISTs), analyzing the morphologic characteristics and stressing the strength of immunohistochemical algorithm for diagnostic purposes. Successively, we have reported the less common group of spindle-shaped MGNs comprehensive of those arising elsewhere the soft tissues, such as leiomyomas, leiomyosarcomas, schwannomas, inflammatory myofibroblastic tumor and intra-abdominal desmoid fibromatosis. Finally, very uncommon spindle-shaped MGNs, like clear cell, follicular dendritic cell, undifferentiated pleomorphic and radiation-induced sarcomas as well as spindle cell dedifferentiated liposarcomas, have been briefly mentioned.