Jejunal calcifying fibrous tumor: A jigsaw puzzle with a pool of diagnostic dilemma

Abstract

Calcifying fibrous tumor (CFT) is a very rare benign fibroblastic tumor featuring a wide anatomical distribution and mimicking various spindle cell tumors. CFT has been documented in soft tissues, gastrointestinal tract (GIT), neck, adrenal glands, and pleura. Within the GIT, it is reported in the stomach, small bowel, large intestine, stomach, esophagus, and appendix. The occurrence of CFTs in the gastrointestinal tract presents a diagnostic dilemma, firstly due to the rarity of the lesion and secondly, due to the occurrence of a variety of other stromal lesions in the gastrointestinal tract with histological features that overlap with CFT. In the jejunum, it is extremely rare. We present one such rare case of jejunal CFT at an unusual age, complicated by jejuno-jejunal intussusception resulting in acute intestinal obstruction.

INTRODUCTION

The calcifying fibrous tumor (CFT) is a rare benign lesion characteristic of hypocellular, bland fibroblastic proliferation embedded in the hyalinized collagenous stroma with chronic inflammation and prominent calcification.^[1] This tumor was first reported by Rosenthal and Abdul-Karim as calcifying fibrous pseudotumor with psammoma bodies and later redefined as calcifying fibrous pseudotumor by Fetsch.^[2] Pseudotumor was used to reflect the belief that the underlying process was most likely inflammatory. The tumor was primarily regarded as a late stage of inflammatory myofibroblast tumor (IMT) but now has been proposed as a distinct fibroblastic tumor.^[1,3,4] However, Nascimento et al.^[1] suggested it as a true neoplasm with a tendency for local recurrence.

CASE PRESENTATION

A 20-year-old male presented with a chief complaint of severe abdominal pain and vomiting. An emergency abdominal X-ray showed air/fluid levels suggestive of intestinal obstruction [Figure 1a]. The general examination was unremarkable. Routine blood investigations were normal. The patient was taken up for an abdominal computed tomography (CT) scan, which revealed moderate to severe dilatation of the jejunum due to intussusception along with a hypodense, enhancing polypoidal mass-like lesion in the jejunum [Figure 1b]. The patient underwent emergency exploratory laparotomy along with segmental resection of the jejunum, and the surgical specimen was sent for histopathological examination. Macroscopically, the jejunal segment measured 7.5 cm in length. The serosa was congested. On the mucosal surface, a well-delineated lobulated mass was noted, measuring 5 × 4 × 3.8 cm³, having a smooth surface with a hard consistency, the cut surface of which was tan-white in color with myxoid areas [Figure 2a and b]. On microscopic examination, a paucicellular fibroblastic proliferation of bland spindle-shaped cells embedded in dense collagenous tissue was noted. Few myxoid areas were noted. There was a varying degree of lymphocytes, plasma cells, and eosinophils scattered throughout, along with small foci of dystrophic or psammomatous calcification [Figure 3a and b]. There was no mitosis or necrosis. In order to distinguish benign spindle cell neoplasms, we considered CFT, gastrointestinal tumors (GIST), schwannoma, and neurofibromatosis as our main differential diagnoses. Immunohistochemical stains were performed, which revealed focal membranous positivity for CD 34 and negativity in tumor cells with SMA, S-100, and CD117. [Figure 3c-f]. Based on histopathological and IHC findings, a final diagnosis of CFT was rendered.

Figure 1: (a) Emergency abdominal X-ray showed air/fluid levels suggestive of intestinal obstruction (b) Abdominal CT scan showing hypodense enhancing polypoidal mass in the jejunum (red arrow)

Figure 2: (a) Surgically removed mass in jejunum intraoperatively (b) Macroscopically, the jejunal segment with a well-delineated, tan-white, hard, lobulated mass on a mucosal surface measuring 5 × 4 × 3.8 cm³ with myxoid areas

Figure 3: Calcifying fibrous tumor (CFT). (a) Histopathology: fibroblastic proliferation of bland spindle-shaped cells in dense collagenous tissue with small foci of dystrophic/psammomatous calcification (Hematoxylin and Eosin ×100), (b) bland spindle-shaped cells with myxoid change (Hematoxylin and Eosin ×400). Immunohistochemistry: (c) CD 34, diffuse membranous positivity in tumor cells (IHC ×400), (black arrow) (d) SMA, negative in tumor cells (IHC ×100). (e) S-100, negative in tumor cells (IHC ×100), (f) CD 117, negative in tumor cells (IHC ×100)

DISCUSSION

CFT is a very rare benign fibroblastic tumor featuring a widely anatomical distribution and may mimic various spindle cell tumors. Its etiopathogenesis has not been fully elucidated yet, but it may be associated with trauma, previous surgical procedures, and chronic infections. The tumor affects people of any age, with tumors of somatic tissues often occurring in children (median age: 3 years), while visceral tumors occur in adults (median age: 43 years) with an equal predilection for males and females.^[5] CFT has been documented at a variety of sites, including soft tissues, neck, GIT, mediastinum, adrenal gland, and pleura. In GIT, CFT is reported in the small bowel, large intestine, stomach, and esophagus and rarely in the appendix and pancreas.^[6] Clinically, the patients are asymptomatic, and occasionally, patients with intra-abdominal soft tissue masses may experience nonspecific symptoms, such as abdominal discomfort or pain and acute intestinal obstruction. CFTs present a diagnostic challenge due to histologic features that overlap with numerous stromal lesions. Understanding the core clinical, histologic, and immunophenotypic features of CFTs is important for making an accurate diagnosis. CFT originates from the subcutaneous and deep soft tissue, and macroscopically, it is a well-circumscribed, nonencapsulated mass that has got a wide range of size and diameter (0.1–25 cm) and can infiltrate the surrounding tissues. Histology shows three characteristic features: Spindle cell proliferation within a densely hyalinized stroma, scattered calcifications, and lymphoplasmacytic inflammation.

Immunohistochemically, CFT is positive for CD34, and negative for CD 117, DOG-1, desmin, and S100.^[7]

The differential diagnosis of CFT depends on its localization. The major diagnostic problem is determining the character of the tumor, which means that it is difficult to distinguish malignant from benign tumors in the preoperative stage. Intra-abdominal CFT may GIST, solitary fibrous tumors, inflammatory IMT, carcinoid tumors, lipomas, reactive nodular fibrous tumors, leiomyoma, schwannoma, inflammatory fibrous polyp (IFP), desmoid-type fibromatosis, retroperitoneal fibrosis, associated fibrous-inflammatory sclerotic infiltrations, calcifying aponeurotic fibroma, neuroendocrine tumors, myomas, cystic lesions, neurofibromas, small bowel desmoids, plexiform fibromyxoma, mesenteric fibromatosis, sclerosing mesenteritis, and adrenal neuroblastoma.^[8]

Nevertheless, the main consideration in the differential diagnosis in our case was GIST, schwannoma, and neurofibromatosis. GIST is much more cellular than CFT, does not consist of hyalinized collagen and calcifications, and is not characterized by chronic inflammation. The mesenteric one has malignant behavior. The cells of GIST are strongly positive for CD117 and CD34. Schwannoma and neurofibromatosis show positivity for S-100.^[4] Keeping IHC in consideration, all our differentials were ruled out.

Treatment of intestinal CFT is primarily aimed at addressing symptoms (obstruction, intussusception, etc.). They are predominantly treated by segmental resection, although enucleation has also been performed. CFT is considered benign and cured by local removal, although rare recurrences have been noted in extra-GI (gastrointestinal) lesions.^[8]

CONCLUSION

The diagnosis of CFT is based on the imaging findings and the pathological findings (histological appearance and immune histochemical studies) owing to the heterogeneity of symptoms. Recognizing CFTs is important because surgery is curative, and their prognosis is much better than that of other soft tissue tumors of the gastrointestinal tract. In an adult with intussusception, a thorough evaluation of the CT findings, along with clinical details, physical and histopathology examination, is warranted for a definite diagnosis. The case was presented to highlight the awareness of this rare lesion at an uncommon location which avoids misdiagnosis and overtreatment.

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Conflicts of interest

There are no conflicts of interest.