ALK-negative lung inflammatory myofibroblastic tumor in a young adult: A case report and literature review of molecular alterations

Inflammatory Myofibroblastic Tumor: A Rare Case Report

Inflammatory myofibroblastic tumors (IMTs) are rare benign tumors that can occur anywhere in the body, most commonly in the pediatric and young adult populations. The gold standard treatment is surgical resection, possibly along with chemotherapy and/or radiotherapy. IMTs have a high recurrence rate and may present with secondary symptoms, such as hemoptysis, fever, and stridor. We present a 13-year-old male patient with hemoptysis for one month who was subsequently diagnosed with an obstructing IMT of the trachea. The preoperative assessment showed the patient was not in acute distress and could protect his airway, even when lying flat. The treatment plan was discussed with the otolaryngologist, to keep the patient spontaneously breathing throughout the case. Anesthesia was induced with boluses of midazolam, remifentanil, propofol, and dexmedetomidine. Doses were adjusted as needed. Glycopyrrolate was also given to limit the patient's secretions before initiating the surgical procedure. The FiO₂ was kept under 30% as tolerated to reduce the risk of airway fire. During surgical resection, the patient was kept spontaneously breathing, and paralytics were avoided. Due to high tumor vascularity and inability to obtain hemostasis, the patient was kept intubated and on ventilation post-operatively until definitive treatment could be performed. On postoperative day 3, the patient returned to the operating room due to a worsening condition. He was found to have a partial obstruction of the right mainstem bronchus by the tumor. More of the tumor was debulked, and he remained intubated above the level of the debulked mass. The patient was then transferred to a higher acuity institution for advanced care. After the transfer, the patient underwent a carinal resection on cardiopulmonary bypass. This case provides insight into successfully sharing the airway during tracheal tumor resection, emphasizing minimizing the risk of airway fire and constant communication with the surgeon.

Inflammatory Myofibroblastic Tumor of the Hilar Bile Duct: A Case Report and Literature Review

Background

Inflammatory myofibroblastic tumor (IMT) is a very rare tumor and occurs seldom in the biliary tract. IMT can occur in any part of the body and in people of any age; however, it most commonly occurs in children or adolescents. Its etiology and pathogenesis are currently unknown. The clinical manifestations of a hilar inflammatory myofibroblastic tumor are atypical, and the imaging examination is nonspecific. The diagnosis is mainly based on histopathology and immunohistochemistry findings, and surgical resection is the preferred treatment method.

Case Description

Herein, we report a rare case of hilar bile duct IMT and review the related literature. Our patient was a 54-year-old woman presenting with a 1-day history of upper abdominal pain as the main clinical symptom. She was misdiagnosed as having cholangiocarcinoma before the surgery. She underwent surgery and was ultimately diagnosed with IMT based on histopathology and immunohistochemistry findings. On 1-year follow-up, no tumor recurrence or related complications were noted.

Conclusions

We hope this case report helps clinicians gain a deeper understanding of biliary IMT of the hilum.

NTRK Fusions in 1113 Solid Tumors in a Single Institution

Most NTRK fusions occur at very low frequencies in various common cancers. Recent recommendations on NTRK testing recommend immunohistochemistry (IHC) as the initial test for tumor types with a low frequency of NTRK fusions. This study investigated the accuracy of an IHC assay to detect NTRK fusions and characterize the clinicopathological and molecular features of NTRK-rearranged tumors. This retrospective study was conducted on 1113 solid tumor samples known to harbor no oncogenic driver alterations, including 510 non-small cell lung cancers (NSCLC), 503 colorectal cancers (CRC), and 79 inflammatory myofibroblastic tumors (IMT). Additionally, 21 ALK expression-positive cases were included. TRK expression was evaluated using a pan-Trk IHC assay, and positive cases were validated using NGS. TRK expression was observed in three NSCLCs (0.6%), six CRCs (1.2%), and six IMTs (6%). NTRK fusions were finally detected in two NSCLCs (0.4%), six CRCs (1.2%), and one IMT (1%). In NSCLC and CRC, the majority of NTRK fusions were readily discernible due to diffuse moderate-to-strong cytoplasmic staining on pan-Trk IHC. In IMT, focal weak nuclear staining indicated the presence of NTRK fusion. Therefore, the utility of pan-Trk IHC should be assessed considering that the difference in performance depends on tumor type.

Inflammatory Myofibroblastic Tumor 12 Years After Treatment for Synovial Sarcoma: A Case Report

Inflammatory myofibroblastic tumors (IMTs) are mesenchymal neoplasms most seen in the abdominopelvic region, lung, and retroperitoneum; and less commonly seen in virtually any other site. We report a case of two lower limb masses consistent with diagnosis of IMTs. This is a 39-year-old woman with a history of right lower extremity popliteal fossa synovial sarcoma diagnosed 12 years prior and treated with chemotherapy, surgery, and radiation. She presented with two new - one anterior and one posterior - right thigh masses. Biopsies of the lesions demonstrated low-grade inflammatory spindle cell lesions at both sites. Wide resection was performed for both masses and further characterization of the surgical specimens was most consistent with IMT. At follow-up, the patient is well with no signs of recurrence 19 and 7 months postoperative to the resection of the anterior and posterior thigh masses, respectively. This case represents the first reported IMTs occurring as late as 12 years after primary cancer treatment, and the first occurring after synovial sarcoma.