Low-grade fibromyxoid sarcoma of the sigmoid colon

A rare case report of pancreatic low-grade fibromyxoid sarcoma (LGFMS)

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is an uncommon neoplasm generally affecting muscle tissue. It presents rarely in abdominal viscera and even more rarely occurs in the pancreas. All types of pancreatic sarcomas are uncommon, and LGFMS is a rarer still. We present the case of an LGFMS in the pancreas. Because of its rarity, there are no guidelines for appropriate treatment or summations of the natural course of this illness.

CASE PRESENTATION

We present the case of a 49-year-old female who presented with epigastric pain. She had a prior history of three episodes of acute pancreatitis many years earlier. A CT revealed a pancreatic body mass, which was biopsied. Pathology returned LGFMS. The patient underwent a distal pancreatectomy and splenectomy. She did well after the case and did not require further intervention.

CONCLUSION

Though it is exceedingly rare, cases of pancreatic LGFMS should be reported in order to guide clinical decisions. LGFMS has been shown to have high malignant potential in other tissues, and there is no reason to think pancreatic masses will be different. By building a body of evidence about these rare tumors, patient care will benefit.

Sarcoma fibromixoide de baixo grau em região paratesticular

Objetivos: relatar um caso raro de sarcoma fibromixoide de baixo grau (SFMBG) em uma localização incomum de modo a reforçar aspectos histopatológicos e imunoistoquímicos relevantes para o reconhecimento desta entidade e o adequado diagnóstico diferencial de massas paratesticulares. Relato de caso: homem de 20 anos, com massa escrotal à direita, cuja análise histopatológica demonstrou a presença de tecido fibroso com áreas mixoides e predominância de células fusiformes. A imunoistoquímica foi positiva para vimentina, com índice de Ki67 de 2%, e negativa para S100, CD-34, beta-catenina, desmina e miogenina. Conclusões: caso raro de SFMBG na região paratesticular que reforça a importância da histopatologia e da imunoistoquímica no diagnóstico desse tumor. Apesar da característica histológica benigna, o SFMBG apresenta altas taxas de recorrência e metástases, sendo essencial o seguimento do paciente. 

Primary Site and Other Prognostic Factors for Fibrosarcoma: An Analysis of the National Cancer Database

Purpose: Fibrosarcoma (FS) is a rare and malignant tumor that can occur in a variety of anatomic sites. The goal of this study is to use the National Cancer Database (NCDB) to analyze various factors affecting overall survival in FS and to be one of the rare studies to characterize the significance of the primary anatomic sites.

Methods: The study cohort included 2,278 patients diagnosed with fibrosarcoma who received surgery from the NCDB. Kaplan-Meier curves, log-rank tests, and a multivariable Cox proportional hazard model were used to analyze the significance of factors affecting overall survival.

Results: The head, face, and neck (HR = 1.44; 95% CI: 1.01-2.05; P = 0.046) and thorax anatomical sites (HR = 1.33; 95% CI: 1.02-1.73; P = 0.035) had a higher increased risk of death in comparison to the lower limb and hip. Compared to patients with private insurance, patients without insurance (HR = 1.99; 95% CI: 1.22 to 3.25; P = 0.006) and patients with Medicaid (HR = 1.99; 95% CI: 1.37 to 2.90; P < 0.001) had decreased overall survival. Patients associated with a zip code-level median household income ≥ $63,000 had a decreased risk of mortality when compared to lower income groups.

Conclusion: In general, older patients with comorbidities, advanced-stage disease, and larger tumors who did not have private insurance and were from areas associated with lower income levels had poorer overall survival. No significant difference in overall survival was associated with receipt of neoadjuvant chemotherapy or neoadjuvant radiation.

Primary small intestine mesenteric low-grade fibromyxoid sarcoma with foci of atypical epithelioid whorls and diffuse DOG1 expression: a case report

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare fibroblastic tumor often involving deep tissue of trunk and lower extremities in young to middle-aged patients. Rarely, LGFMS can occur in other sites including head and neck, chest, abdomen and female reproductive system. Three cases of LGFMS in mesentery of small intestine have been reported and all have conventional histologic features. Herein we reported a unique case of LGFMS in mesentery of small intestine.

CASE PRESENTATION

A 43 year-old male with chief complaint of lower back pain for 4 years presented to our hospital. Physical exam reveal a firm, non-tender, non-distended, mobile large abdominal mass, which was shown on abdominal CT as a 10 cm retroperitoneal tumor. Biopsy revealed a spindle cell neoplasm in a myxoid background with a delicate vascular network. Tumor resection was performed. Gross examination of the resected specimen showed a 10.8 cm, tan-white, smooth, firm, lobulated mesenteric mass with bulging and gelatinous cut surface and confined within small bowel serosa. Microscopic examination demonstrated foci epithelioid cords and whorls with prominent atypia, in additional of regular, bland-appearing spindle cells in a fibrous and myxoid stroma and osseous metaplasia. The tumor cells stained diffusely positive for DOG1 with moderate staining density, and diffusely and strongly positive for MUC4. Rearrangement involving FUS (16p11.2) gene was identified with break-apart probe and confirmed by Anchored Multiplex PCR. A final diagnosis of low-grade fibromyxoid sarcoma was rendered.

CONCLUSION

Our case highlights the importance of including LGFMS in the differential diagnosis of mesenteric tumors and the DOG1 positivity which could represent a potential diagnostic pitfall.

Huge mesenteric low-grade fibromyxoid sarcoma: A case report and review of the literature

Low-grade fibromyxoid sarcoma is a rare soft tissue tumor which has been mostly reported in lower extremities; however, it can also occur in other parts of the body such as head and neck and abdominal wall, but its occurrence in the abdominal cavity and mesentery of bowel is an extremely rare event and has very rarely been reported. Herein, we report our experience with a 24-year-old lady with a huge mesenteric mass, turned out to be low-grade fibromyxoid sarcoma. This case is the largest one reported in the English literature. We will also discuss about the previously reported cases of low-grade fibromyxoid sarcoma in the English literature.

Abdominopelvic and Retroperitoneal Low-Grade Fibromyxoid Sarcoma: A Clinicopathologic Study of 13 Cases

OBJECTIVES

Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor often arising in the lower extremities. Only rare examples in the abdominal cavity, pelvis, and retroperitoneum have been reported.

METHODS

cases of abdominopelvic and retroperitoneal LGFMS were retrieved. MUC4, Actin, ALK, β-catenin, desmin, DOG1, KIT, S100 protein, and STAT6 testing was performed, and a subset was tested for FUS rearrangement.

RESULTS

Sites included intra-abdominal/abdominal wall (four cases), retroperitoneum (three cases), pelvis (three cases), small bowel (two cases), and kidney (one case) (median size, 15 cm; age range, 5-61 years). Tumors harbored spindled cells with mild to moderate atypia, displaying alternating myxoid nodules and hyalinized areas. All cases were positive for MUC4, and five (of five) cases tested harbored FUS rearrangement. Variable positivity for DOG1 (four of 10) and actin (two of 10) was identified. Six tumors recurred, and one patient developed metastasis.

CONCLUSION

LGFMS arising in these central locations exhibits similar clinicopathologic features to its counterpart in the extremities. LGFMS at these sites may show limited immunoreactivity for DOG1 and actin.

Low-grade fibromyxoid sarcoma of the external anal sphincter: a case report

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue tumor that has a tendency to grow in the deep soft tissue of the trunk and extremities. Despite its benign appearance, the tumor has a high recurrence rate and metastatic potential. LGFMS in the perineal space is rare, and only a few cases have been reported. We present the first case of LGFMS to be located at the external anal sphincter.

CASE PRESENTATION

A 27-year-old male patient admitted to our Surgical Department with perianal pain and swollen for a year. The digital rectal examination revealed a perianal mass. Oral metronidazole and analgesia were prescribed on suspicion of perianal abscess failed to alleviate the symptom; hence, the patient was scheduled for surgery. Intraoperative diagnosis revealed an encapsulated tumor in the external anal sphincter that extended from the perianal region orally to the pararectal space. The results of immunohistochemistry (MUC4 staining) and FUS gene rearrangement by fluorescence in situ hybridization confirmed the diagnosis of LGFMS.

CONCLUSIONS

This case is unique in terms of the location of the rare soft tissue tumor. Although LGFMS is considered low grade, its unpredictable behavior necessitates a long-term follow-up.