A case of cutaneous inflammatory myofibroblastic tumor

Cutaneous Inflammatory Myofibroblastic Tumor with CARS-ALK Fusion: Case Report and Literature Review

Cutaneous inflammatory myofibroblastic tumors (IMT) constitute a rare entity, generating a diagnostic pitfall when diagnosing spindle cell proliferation within the dermis. Raising awareness of this tumor among dermatopathologists remains vital in differentiating it from common cutaneous tumors such as fibrous histiocytoma, atypical fibroxanthoma, melanoma, poorly differentiated carcinoma, and other more aggressive tumors. Accurate diagnosis of IMT aid in ensuring appropriate management and follow-up for patients while preventing unnecessary harm and overtreatment. Here we report a case of a 38-year-old female with a painless, slow-growing nodule of the left posterior scalp initially diagnosed as a dermatofibroma. The histological examination revealed an ill-defined dermal nodule of spindled cells without connection or infiltration of the epidermis. At high power, the cells were arranged in fascicles with a prominent background of lymphocytic infiltrate. Immunohistochemical analysis showed strong diffuse immunoreactivity for anaplastic lymphoma kinase (ALK), targeted RNA sequencing identified a CARS-ALK fusion ultimately confirming the accurate diagnosis of a cutaneous IMT. This article is protected by copyright. All rights reserved.

Rare presentation of inflammatory myofibroblastic tumor on a digit

Inflammatory myofibroblastic tumors (IMTs) are rare soft tissue neoplasms consisting of a mixture of spindle-shaped myofibroblasts or fibroblasts and a variable inflammatory infiltrate composed of eosinophils, plasma cells, and lymphocytes. Associations with trauma and infectious agents have been proposed, but the etiology is unknown. While IMT predominantly develops in the lungs of pediatric patients or young adults, extrapulmonary IMT is well documented and may occur anywhere. Cutaneous IMT is rare and few have been reported on the hand in the English language. The mean age of onset is 10 years, with a slight female predilection. IMT demonstrates intermediate malignant potential, with a tendency to recur locally. Metastases are rare. According to a recent review, anaplastic lymphoma kinase (ALK) positivity on immunohistochemistry is related to local recurrence, but not distant metastases. We report an unusual case of a 36-year-old male, with a lesion on the right second digit, displaying classic histopathologic and immunohistochemical features of IMT, including ALK staining, and confirmatory fluorescence in situ hybridization-proven ALK gene rearrangement.

Inflammatory myofibroblastic tumors in children

BACKGROUND

Inflammatory myofibroblastic tumor (IMFT) is an uncommon neoplasm in children.

METHODS

Retrospective review from 1993 to 2014 of patients ≤18years of age with a histopathologic diagnosis of IMFT treated at two tertiary centers.

RESULTS

Thirty-two patients were diagnosed with IMFT. Mean (±SD) age was 9.3±5.7years at diagnosis. Tumor location was variable: abdomen/pelvis (28%), head/neck region (22%), intrathoracic (22%), genitourinary (9%), bowel (6%) liver (6%), and musculoskeletal (6%). Median follow-up was 2.6±4.6years, with 3 recurrences and 2 deaths, which occurred only after recurrence. Positive microscopic margin after resection was associated with recurrence, compared to those that had a negative margin (40% vs. 0%, p=0.04). Recurrence was associated with increased mortality (67% vs 0%, p=0.01). Time from first symptoms to resection was shorter in those with recurrence (25.8±22 vs. 179±275days, p=0.01) and in nonsurvivors (44.0±8.0 vs. 194.3±53.4days, p=0.02). Adjuvant chemotherapy, not including steroid monotherapy, either given before or after resection, was administered more often to nonsurvivors (100% vs 4%, p=0.009), and use of corticosteroids was also higher in the nonsurvivors (100% vs. 15%, p=0.04).

CONCLUSIONS

IMFT is a rare pediatric neoplasm with variable locations. Complete excision is critical for cure. Proposed guidelines for diagnosis, treatment and surveillance of theses tumors in children are reported.

Focal hand lesions: review and radiological approach

Focal hand lesions are commonly encountered in clinical practice and are often benign. Magnetic resonance (MR) imaging is the imaging modality of choice in evaluating these lesions as it can accurately determine the nature of the lesion, enhancement pattern and exact location in relation to surrounding tissues. However, while MR features of various soft tissue lesions in the hand have been well described, it is often still difficult to differentiate between benign and malignant lesions. We review the MR imaging features of a variety of focal hand lesions presenting at our institution and propose a classification into "benign", "intermediate grade" (histologically benign but locally aggressive with potential for recurrence) and frankly "malignant" lesions based on MR findings. This aims to narrow down differential diagnoses and helps in further management of the lesion, preoperative planning and, in cases of primary malignancy, local staging. Teaching Points • Hand lesions are often benign and MR is essential as part of the workup. • MR features of various hand lesions are well described but are often non-specific. • Certain MR features may help for the diagnosis but histological examination is usually required. • We aim to classify hand lesions based on MR features such as margin, enhancement and bony involvement. • Classifying these lesions can help narrow down differential diagnoses and aid management.

Anaplastic lymphoma kinase (ALK1) immunohistochemistry in diagnostic dermatopathology; an update

The use of anaplastic lymphoma kinase antibodies (ALK1) as a diagnostic aid has expanded since becoming a routinely available immunohistochemical stain. Because the skin may be the site of a wide variety of hematolymphoid and fibroblastic proliferations, dermatopathologists commonly use ALK1 as part of a broader staining panel in diagnosing soft tissue and cutaneous hematolymphoid neoplasms. Furthermore, new entities and differential diagnostic contexts are emerging, which broaden the utility of ALK1 immunohistochemistry. We review the expanding role of ALK1 immunohistochemistry in contemporary dermatopathology.

Inflammatory myofibroblastic tumour of the bladder: Case report and review of the literature

Inflammatory myofibroblastic tumour (IMT) is a rare tumour with malignant potential, and has been described in many major organs. However, bladder location is very uncommon. We report the case of a 23-year-old woman who presented with painless gross hematuria for 2 weeks. Contrast-enhanced computed tomography revealed a bladder tumour. The patient underwent an open partial cystectomy and the final pathologic diagnosis was IMT of bladder. Typical IMTs can be locally aggressive, therefore close follow-up is necessary.

Soft-tissue inflammatory myofibroblastic tumors (IMTs) of the limbs: potential and limits of diagnostic imaging

OBJECTIVE

The objective of this work was to evaluate the potential of diagnostic imaging in the identification, localization, and characterization of soft-tissue inflammatory myofibroblastic tumors (IMTs) of limbs with correlation to differential diagnosis and therapy.

MATERIALS AND METHODS

From a retrospective analysis of 324 histologically verified soft-tissue lesions of limbs and extremities diagnosed in our institute from January 2002 to July 2010, we selected seven cases of histologically proven IMT. These included six males and one female, aged between 28 and 81 years (mean age, 57 years). Lesions were localized in three cases to the thigh, in two cases to the popliteal space, and in the remaining two cases, to the shoulder girdle. All patients were evaluated on the basis of US, CT, and MRI.

RESULTS

Ultrasound detected the presence of a non-homogeneous solid formation in all cases and calcifications in three cases. CT showed the presence and type of calcification/ossification and bone reaction. On MRI, all cases had low signal intensity on SE T1-weighted sequences and an intermediate-low signal intensity on SE and FSE T2-weighted sequences in six of them; only one case had an intermediate-high signal intensity on SE and FSE T2-weighted sequences. Both contrast-enhanced CT and MRI showed precocious enhancement in association with multiple peripheral hypertrophic blood vessels.

CONCLUSIONS

On the basis of integrated imaging data obtained by US, CT, and MRI, it is possible to evaluate the lesion extension to provide a loco-regional staging, to characterize IMTs, and to allow an optimal therapeutical planning.