Pathological Complete Response of Clinical T4b Ascending Colon Cancer after Preoperative Chemotherapy Using Pembrolizumab

Preoperative chemotherapy is efficacious in several cancers. However, it is not an established treatment for locally advanced colon cancer, particularly cases with microsatellite instability-high (MSI-H)/deficient mismatch repair. Herein, we report a case of pathological complete response of MSI-H clinical T4b ascending colon cancer to preoperative treatment with pembrolizumab. A 78-year-old man was diagnosed with ascending colon cancer that invaded into the iliacus muscle and enlarged regional lymph nodes. The tumor was classified as T4bN1bM0 stage IIIC according to the 8th Union for International Cancer Control guidelines, with MSI-H status. Based on our initial diagnosis, this tumor could not be resected completely. Thus, the patient underwent preoperative therapy with CAPOX (capecitabine and oxaliplatin combination) plus bevacizumab. After 4 cycles of preoperative CAPOX/bevacizumab, we observed tumor reduction corresponding to a partial response based on the Response Evaluation Criteria in Solid Tumors criteria. Nevertheless, tumor invasion of the iliacus muscle persisted. Since oxaliplatin-induced peripheral sensory neuropathy was observed, we discontinued treatment with oxaliplatin and changed the regimen to pembrolizumab in anticipation of the therapeutic effect of this immune checkpoint inhibitor against MSI-H tumors. After 2 cycles of therapy with pembrolizumab (200 mg/body on day 1 every 3 weeks), there was drastic tumor regression. In addition, computed tomography indicated that all lymph node metastases had disappeared. Therefore, the patient underwent laparoscopic right hemicolectomy with D3 lymph node dissection. Analysis of the resected specimen showed pathological complete response.

Development of an Iliacus Muscle Abscess after School Exercise in a 17-Year-Old Female Student

Primary psoas abscess is due largely to hematogenous or lymphatic spread under immunocompromised conditions, whereas secondary psoas abscess is due largely to direct spread from adjacent infected structures. Trauma or hematoma within the muscle may predispose to the development of a primary abscess, especially if infection is present prior to injury, despite the absence of previous signs or symptoms of infection. This report describes a 17-year-old female high school student who developed an abscess within her iliacus muscle due to methicillin-susceptible <i>Staphylococcus aureus</i> after running 3 km on a hill as a school exercise. She was positive for antinuclear antibody and had had atopic dermatitis, suggesting that these factors, as well as exercise-related minor trauma or hematoma within the muscle, may have predisposed to abscess formation. She was treated with appropriate antibiotics and surgical drainage, resulting in recovery after 4 weeks.

Adolescent Male with Severe Groin Pain Due to Traumatic Injury

Case Presentation: A 14-year-old boy presented to the emergency department complaining of severe groin pain on the right side following a minor fall. Computed tomography and magnetic resonance imaging revealed a hematoma in his right iliacus muscle. He was diagnosed with a traumatic iliacus hematoma, and he recovered spontaneously with short-term oral analgesics. Discussion: Traumatic iliacus hematomas are rare entities and subside with conservative management in most cases. However, this condition may be associated with femoral nerve palsy, and surgery is indicated in severe cases. Traumatic iliacus hematoma should be considered in the differential diagnosis of severe groin pain.

A Rare Case of Recurrent Phyllodes Tumor of Bilateral Breasts with Metastasis to the Retroperitoneum and Duodenum

Phyllodes tumors are uncommon fibroepithelial tumors of the breast. These tumors are graded based on the World Health Organization criteria into benign, borderline, and malignant subtypes. While benign phyllodes tumors are by far the most common presentation, borderline and malignant tumors have important clinical implications, as they are more likely to locally recur and metastasize. The most common sites of distant metastasis include the lung, bone, heart, and liver. Rare spread to the small intestines, kidney and pelvis have also been reported. We report a case of a 71-year-old woman with a history of locally recurrent phyllodes tumor of the breasts found to have retroperitoneal and intraperitoneal metastases. The retroperitoneal mass was just below the left kidney, extending into the pelvis, and overlying the psoas and iliacus muscle. The second mass involved the second portion of the duodenum, the proximal transverse colon, and the overlying mesentery. This is a rare case of delayed metastatic spread of phyllodes tumor to two sites, seventeen years after first presentation.

Spontaneous muscle hematoma complicating dengue hemorrhagic fever: a case report

Dengue is endemic in Bangladesh and is an emerging infection in many parts of the world. Its clinical manifestations are wide spectrum, may present as mild fever to shock. Muscle hematomas are rare complications in dengue hemorrhagic fever. We report a case of 21-year-old male with dengue hemorrhagic fever who developed right sided iliacus muscle hematoma. He presented with fever, progressive thrombocytopenia and evidence of plasma leakage. During the recovery phase, he developed severe pain in right hip during movement. Diagnosis was confirmed by pelvic computed-tomography scan and he was managed conservatively. Birdem Med J 2020; 10(1): 76-77

Spontaneous Progressive Muscle Weakness with Persistent Leukocytosis

Iliacus compartment syndrome is a rare clinical condition which can result in a severe, unilateral, femoral neuropraxia. Recognition of this syndrome as the cause of a developing neuropathy is often delayed given a lack of familiarity with this clinical diagnosis and the retroperitoneal location of the iliacus muscle. Prompt diagnosis is important to avoid risk of consequent muscle necrosis, rhabdomyolysis, and possibly permanent nerve injury. We describe a case of iliacus compartment syndrome in an elderly, frail woman with end-stage renal disease, anticoagulated for atrial fibrillation, who presented with subacute, progressive lower extremity muscle weakness and pain in the setting of complicated metabolic derangements. She was found to have a spontaneous large hematoma in her left iliacus muscle on computed tomography scan. Despite an initial diagnostic delay, she was successfully managed with an iliacus fasciotomy, which led to complete resolution of her symptoms.