Aggressive gluteal fibromatosis: a rare case associated with spontaneous superior gluteal artery pseudoaneurysm.

Deep fibromatosis is a locally aggressive neoplasm commonly involving the extremities. Several authors have described imaging features and complications associated with deep fibromatosis. We present the case of a 33-year-old man who presented with a right gluteal fibrous mass identified on magnetic resonance imaging (MRI), which was associated with a pseudoaneurysm originating from the right superior gluteal artery on serial follow-up with MRI and computed tomography. No intervention was done, and after conservative management, spontaneous thrombosis of the pseudoaneurysm was developed. Such imaging finding is the first report of a spontaneous development of pseudoaneurysm caused by deep fibromatosis, which could be a life-threatening condition and should be considered when dealing with deep fibromatosis and deciding on the appropriate treatment.

The largest malignant peripheral nerve sheath arising from the gluteal region: case report.

We report a unique case of a huge malignant peripheral nerve sheath tumor with probable smooth muscle differentiation.

It is all about form and function: a new approach to giant neonatal sacrococcygeal teratomas.

INTRODUCTION: Giant sacrococcygeal teratomas (GSCTs) involve severe deformation of the buttock region in addition to potential functional impacts. Little interest has been given to improving the aesthetic post-operative appearance in children with these tumours. METHODS: We describe a new technique for immediate reconstruction of GSCTs using buried dermal-fat flaps and a low transverse scar in the infragluteal fold. RESULTS: Our technique allows wide exposure for tumour resection and functional restoration of the pelvic floor while placing the scars in anatomical locations and restoring buttock aesthetics including gluteal projection and infragluteal fold definition. CONCLUSION: Reestablishment of function and form should be kept in mind at initial surgery in GSCT surgery to maximize results and enhance post-operative outcomes. LEVEL OF EVIDENCE: IV.

[A Case of Triple Negative Breast Cancer with Left Buttock Metastasis].

A female patient in her 50s was diagnosed with triple negative breast cancer in the left breast with a buttock metastasis. After neoadjuvant chemotherapy, the patient underwent surgery on the left breast. As the histopathological findings indicated a residual tumor, she was further treated with capecitabine postoperatively. Twenty months postoperatively, a CT scan revealed a tumor on her left buttock. She was also diagnosed with a relapse of the breast cancer after a core needle biopsy. She was treated with atezolizumab and nab-paclitaxel as first-line therapy for the metastasis and with eriburlin as second- line therapy. As she became uncomfortable sitting owing to the regrowth of the buttock tumor, the left buttock tumor was resected. She has been treated with bevacizumab and paclitaxel for subsequent lung metastases.

Indolent expanding plaque with satellites on buttocks.

A 74-year-old man was referred with a 10-year history of a plaque on the left buttock. Prior to presentation to dermatology, he had undergone biopsy under plastic surgery for a presumptive diagnosis of psoriasis, but histology was nonspecific. Further clinical examination and repeat biopsies were needed for the diagnosis.

MRI Findings of Muscle Damage after Total Hip Arthroplasty Using the Complete Muscle Preserving Anterolateral Supine Approach.

Background and Objectives: We performed anterolateral total hip arthroplasty (ALS THA) with the purpose of complete muscle-tendon preservation without muscle-tendon dissection. This study aimed to evaluate muscle damage in the periprosthetic hip joint muscles of patients undergoing ALS THA at 1-year post-operative hip magnetic resonance imaging (MRI). Materials and Methods: We evaluated changes in the muscle cross-sectional area (M-CSA) and fatty atrophy of the periprosthetic muscles. We also assessed the Harris hip score on pre-operative and 12-month post-operative MRI in 66 patients who underwent ALS THA. The grade of M-CSA atrophy was classified into no atrophy, slight atrophy, moderate atrophy, and severe atrophy. Fatty atrophy was classified as improved, no change, and worsened using the Goutallier classification. Results: More than 90% of patients' M-CSA had no atrophy in the obturator internus (Oi), obturator externus (Oe), gluteus medius (Gmed), and gluteus minimus (Gmin), and some improvement was observed in terms of fatty atrophy. In contrast, M-CSA of the tensor fascia latae (TFL) muscle was clearly decreased, and there was no improvement in the TFL fatty atrophy. However, the presence or absence of TFL atrophy did not affect clinical outcome. Conclusions: We performed the complete muscle preserving procedure, ALS THA, with attention to preserving the Oi and Oe by direct visual confirmation and gentle treatment of the Gmed and Gmin with effective retraction. Post-operative M-CSA atrophy evaluation on MRI showed that the Oi, Oe, Gmed, and Gmin were satisfactorily preserved; however, the TFL was clearly atrophic. In the ALS approach, where entry is made between Gmed and TFL, atrophy of the TFL due to superior gluteal nerve injury must be tolerated to some extent.

Symmetric drug-related intertriginous and flexural exanthema: Clinicopathologic study of 19 cases and review of literature.

BACKGROUND: Symmetric drug-related intertriginous and flexural exanthema (SDRIFE) is a cutaneous drug reaction characterized by gluteal/anogenital erythema and symmetric involvement of other intertriginous location(s) without systemic signs. Clinicopathologic characterization has been limited to case reports and small series. We describe 19 new cases and review the literature to better define the clinical and histopathologic spectrum of SDRIFE. METHODS: Pathology archives were searched for "SDRIFE" and "baboon syndrome." Cases meeting clinical criteria were included. Clinical and histopathologic features were recorded. Previous reports of SDRIFE with histopathologic descriptions were reviewed. RESULTS: Nineteen new cases were included, over half triggered by antibiotics. Six new causative medications were identified. Median onset was 7 days. Typical lesions were erythematous plaques or papules with or without scale. The most common histopathologic finding was superficial perivascular lymphocytic infiltrate followed by dermal eosinophils, spongiosis, and orthokeratosis. Basal vacuolization and apoptotic keratinocytes were less common. Interstitial histiocytes were present in almost half of our cases. Other findings included atypical lymphocytes and "flame figure." CONCLUSIONS: Appreciation of the range of inciting medications and clinicopathologic features in SDRIFE will improve recognition of this condition. Although many histopathologic features overlap with other common dermatitides, biopsy may assist in excluding key clinical mimics.

Coexistence of three nevus lipomatosus cutaneus superficialis with typical, cutaneous adenolipoma-like, and dermal spindle cell lipoma-like histopathological features in a patient.

We report an unique case of a patient who showed coexistence of three nevus lipomatosus cutaneus superficialis (NLCS) with typical, cutaneous adenolipoma (AL)-like, and dermal spindle cell lipoma (SCL)-like histopathological features. A 53-year-old woman presented with a 20-year history of skin-colored and slightly elevated nodules. These lesions were separately located on the lateral side (lesion 1) and medial side (lesion 2) of her left buttock and on her right thigh (lesion 3). Microscopically, all were ill-defined dermal lesions with some subcutaneous involvement and were mostly composed of mature adipocytes. The adipocytes formed small aggregates around blood vessels in the upper dermis. Lesions 1, 2, and 3 were diagnosed as NLCS, and additional features were recognized in lesions 2 and 3. Lesion 2 revealed eccrine glands and ducts amongst the lipomatous component, as seen in cutaneous AL. Lesion 3 had scattered CD34-positive spindle cells, which is representative of dermal SCL. These appearances were considered to be on the morphological spectrum of NLCS. In all three lesions, CD34-positive cells proliferated between the upper dermal blood vessels and their peripheral mature adipocytes. This pathological finding could be principal in NLCS and might be associated with its pathogenesis.

Development of sacral/buttock retiform purpura as an ominous presenting sign of COVID-19 and clinical and histopathologic evolution during severe disease course.

Retiform purpura has been described as a relatively frequent cutaneous finding in patients with coronavirus disease 2019 (COVID-19). The etiology is hypothesized to be related to thrombotic vasculopathy based on lesional biopsy specimen findings, but the pathogenesis of the vasculopathy is not completely understood. Here, we present a case of a retiform purpuric patch on the sacrum/buttocks in a hospitalized patient prior to subsequent diagnosis of COVID-19 and an eventual fatal disease course. Two lesional biopsy specimens at different time points in the disease course revealed thrombotic vasculopathy, despite therapeutic anticoagulation. Detailed histopathologic evaluation using immunohistochemical markers suggest the etiology of the vasculopathy involves both persistent complement activation and platelet aggregation, which possibly promote ongoing thrombus formation. This case highlights that sacral/buttock retiform purpuric patches may be a presenting sign of infection with SARS-CoV-2 virus and may represent an ominous sign supporting a future severe disease course. In addition, biopsy specimen findings at separate time points demonstrate that cutaneous vasculopathy may persist despite adequate systemic anticoagulation, possibly due to the combination of persistent complement and platelet activation. Finally, occlusive thrombi in sacral/buttock retiform purpuric patches may contribute to future ulceration and significant cutaneous morbidity in patients who survive COVID-19.

Cytological features of BCOR-CCNB3 sarcoma: Comparison with Ewing sarcoma and synovial sarcoma.

INTRODUCTION: BCOR-CCNB3 sarcoma (BCS) is one of the histological types classified as an undifferentiated small round cell sarcoma of bone and soft tissue. This sarcoma frequently develops in males under 20 years of age. Histologically, a delicate capillary network has been reported as a conspicuous finding. In this study, the cytological findings of BCS were observed in two cases of primary lesions and one case of a lung metastatic lesion. The cytological findings of BCS were compared with its histological mimics, and the characteristic findings of BCS were examined. METHODS: Three cases of BCS were studied, and a cytological comparison was performed with 8 cases of Ewing sarcoma (ES) and 10 cases of synovial sarcoma (SS; monophasic type: 7 cases, biphasic type: 2 cases, poorly differentiated: 1 case). RESULTS: In all BCS cases, small clusters with thin and delicate vascular cores and tiny vascular fragments were conspicuous. In ES and SS cases, although small clusters with vascular cores were observed, the vascular cores were thicker than in BCS, and no tiny vascular fragments appeared in most cases. Cytomorphological differences of tumour cells were also observed among BCS, ES, and SS. Predominantly rounded nuclei with fine chromatin and inconspicuous nucleoli can be cytological clues for BCS. CONCLUSIONS: BCS shows characteristic cytological findings that make the diagnosis of BCS more likely than that of ES and SS. Cytological evaluation is a useful tool for appropriate differential diagnosis that leads to a more accurate final diagnosis and rapid treatment.

Surgical Release of Gluteal Fibrosis in Children Results in Sustained Benefit at 5-Year Follow-up.

BACKGROUND: Gluteal fibrosis (GF) is a fibrotic infiltration of the gluteal muscles resulting in functionally limiting contracture of the hips and is associated with injections of medications into the gluteal muscles. It has been reported in numerous countries throughout the world. This study assesses the 5-year postoperative range of motion (ROM) and functional outcomes for Ugandan children who underwent surgical release of GF. METHODS: A retrospective cohort study of children who underwent release of GF in 2013 at Kumi Hospital in Eastern Uganda. Functional outcomes, hip ROM, and scar satisfaction data were collected for all patients residing within 40 km of the hospital. RESULTS: One hundred eighteen children ages 4 to 16 at the time of surgery were treated with surgical release of GF in 2013 at Kumi Hospital. Of those 118, 89 were included in this study (79.5%). The remaining 29 were lost to follow-up or lived outside the study's radius. Detailed preoperative ROM and functional data were available for 53 of the 89 patients. In comparison with preoperative assessment, all patients postoperatively reported ability to run normally (P<0.001), sit upright in a chair (P<0.001), sit while eating (P<0.001), and attend the entire day of school (P<0.001). Passive hip flexion (P<0.001) improved when compared with preoperative measurements. In all, 85.2% (n=75) of patients reported satisfaction with scar appearance as "ok," "good," or "excellent" 29.2% (n=26) of patients reported back or hip complaints. CONCLUSIONS: Overall, the 5-year postoperative outcomes suggest that surgical release of GF improves ROM and functional quality of life with sustained effect. LEVEL OF EVIDENCE: Level IV-case series.

Diagnostic challenge of soft tissue extranodal Hodgkin lymphoma in core-needle biopsy: case report.

Hodgkin lymphoma (HL) is an uncommon malignancy usually limited to the lymph nodes and lymphatic system while extranodal involvement is much less common than in non-Hodgkin lymphoma. The current report presents an unusual case of primary classical HL (cHL), nodular sclerosis type with mixed cellularity in buttock soft tissue of 78-year old man. Primary lymphoma of the gluteal muscle is a rare disease and primary cHL is even rarer. In addition, to this unusual extranodal presentation, the present case highlight a diagnostic challenge in fine-needle biopsy masquerading a low grade sarcoma, primarily myxoinflammatory fibrosarcoma or an inflammatory lesion. However, surgical biopsy and immunohistochemistry guided correct diagnosis that was of major interest for further successful treatment.

Vulvar Silicone Granuloma.

We report a case of vulvar silicone granulomas following injection of liquid silicone into the labia. The patient is a 51-yr-old female who presented with vulvar pain and enlarged, indurated labia majora. In the past, she had undergone bilateral labial cosmetic augmentation with a silicone-based filler injected directly into the labia and into the gluteal regions. This had been performed in a nonmedical setting. At surgery, oblong firm soft tissue masses were removed from both labia. Microscopically, the lesions demonstrated replacement of the subcutaneous adipose tissue by fibrous tissue containing innumerable round empty spaces of different sizes, either within or surrounded by macrophages and occasional foreign-body giant histiocytes. The clear vacuoles corresponded to silicone fluid which had been dissolved during tissue processing. There are only rare case reports of vulvar silicone granuloma in the literature, and these were due to migration of silicone to the vulva from distant sites. Our report details a case of vulvar silicone granuloma secondary to direct injection of liquid silicone material into the labia.

Arthrokatadysis from post-injection gluteal muscular fibrosis case report.

BACKGROUND: Gluteal muscle contracture (GMC) is a clinical syndrome characterized by the contracture of gluteal muscles, iliotibial band (ITB), and related fascia. GMC is much more prevalent in China, which has been proven to be associated with repeated intramuscular injections into the buttocks and the subsequent fibrosis and contracture.Generally, GMC is manifested mild. Here, we reported a severe case with arthrokatadysis. CASE PRESENTATIONS: A 25-year old man received multiple intramuscular injections of penicillin in the buttock when he was diagnosed with acute tonsillitis at 6 years old. Since then, he was injected penicillin regularly in local hospital because of the repeated acute tonsillitis until he was in high school. When the patient was found by the physical education teacher to be running in a state of external rotation of both feet, he was suggested to go to the hospital for treatment and was initially diagnosed to have GMC. He complained of occasional pain and limited range of motion in the hip joints. X-ray showed a typical arthrokatadysis. After arthroscopic release of GMC, the patient recovered well. CONCLUSIONS: This is possibly the first reported case of arthrokatadysis that was caused by GMC after repeated intramuscular injections into the buttocks. Although the patient recovered well by arthroscopic surgical release of bilateral gluteus maximus contractures, GMC should be paid more attention and treated as early as possible.

Concomitant bilateral elastofibroma in the infrascapular and gluteal regions: a report of a rare case.

BACKGROUND: Elastofibroma is a benign soft tissue tumor characterized by the presence of elastic fibers in a stroma of collagen and mature adipose tissue. It is reported to have a prevalence of 2.73%, as shown by a study through computed tomography (CT) images. However, multiple elastofibromas are uncommon. CASE PRESENTATION: We report a case of concomitant bilateral elastofibroma in the infrascapular and gluteal regions. A 63-year-old male patient presented with a 6-month history of gradually increasing painless swellings in the upper back. On physical examination, firm, painless bilateral infrascapular masses were identified; these masses were more noticeable on forward arm flexion. Contrast-enhanced computed tomography showed well-defined bilateral infrascapular masses deep to the serratus anterior muscles as well as poorly defined bilateral gluteal masses with attenuation similar to that of the adjacent skeletal muscle. Magnetic resonance imaging revealed heterogenous masses with internal fatty streaks, consistent with elastofibroma. The histopathological diagnosis of elastofibroma was established based on the results of image-guided core-needle biopsy. The patient underwent surgical excision of both infrascapular elastofibromas with no post-operative complications. As the gluteal masses were incidental, surgical management was not warranted. CONCLUSION: The presence of multiple elastofibromas is unusual. This report describes a rare case of multiple elastofibromas and its typical imaging features, and alerts us that elastofibromas are not exclusive to the periscapular region.

Hip abductor tears in ischiofemoral impingement.

PURPOSE: Ischiofemoral impingement (IFI) is associated with abnormalities of the quadratus femoris muscle and narrowing of the ischiofemoral (IF) and quadratus femoris (QF) spaces. The hip abductors play an important role in pelvic stability and abductor tears might play a role in the pathophysiology of IFI. The purpose of our study was to assess the association between hip abductor tears and IFI on MRI. MATERIALS AND METHODS: The study was IRB approved and HIPAA compliant. Inclusion criteria were MRI findings of IFI (narrowing of the IF space ≤ 15 mm or QF space ≤ 10 mm with associated ipsilateral quadratus femoris edema or fatty infiltration/atrophy). Two MSK radiologists assessed hip/pelvic MRIs and integrity of the tensor fascia lata, gluteus medius, and minimus tendons. IFI and control groups were compared with a two-tailed Student t test or chi-squared test. RESULTS: We identified 140 patients with MRI findings of IFI (mean age 56 ± 13 years, 130 f, 10 m) and 140 controls of similar age and sex. Patients with IFI had a higher prevalence of gluteus medius/minimus partial tears (37 vs 21, p = 0.02) and full-thickness tears (24 vs 21, p = 0.03). Patients with IFI had a higher prevalence and higher grade of gluteal muscle atrophy compared with controls (p < 0.03). There were no tears of the tensor fascia lata in either group. CONCLUSION: Patients with IFI had a higher prevalence of abductor tears and abductor muscle atrophy compared with matched controls. This suggests that abductor tears might play a role in the pathophysiology of IFI.

A Giant Squamous Cell Carcinoma Arising in a Patient with Hidradenitis Suppurativa.

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease of follicular pilosebaceous units. Chronic, active, and poorly controlled disease may lead to squamous cell carcinoma (SCC). The diagnosis and treatment of SCC in HS is particularly challenging because SCC lesions may be easily mistaken for HS lesions. Current medical literature recommends aggressive surgical excision with at least 2-cm margins. In this article, the authors describe a giant perianal SCC arising in a patient with HS who was treated with surgical resection and radiotherapy.

PD1 inhibitor induced inverse lichenoid eruption: a case series.

The increased use of monoclonal antibodies that target the immune checkpoint T cell receptor programmed death-1 (PD1) to treat numerous solid tumors has led to several reports describing associated cutaneous adverse events. Although lichenoid reactions have been well described, we propose that PD1 inhibitor-induced inverse lichenoid eruption (PILE) is a distinct variant. We describe two patients who presented with nearly identical deeply erythematous, malodorous, eroded anogenital plaques with focal crusting. Diagnosis of PILE was established given the biopsy findings and temporal association with PD1 inhibitor therapy. Treatment with clobetasol ointment was successful without necessitating discontinuation of immunotherapy. The findings were consistent with the only other previously published case of inverse lichenoid eruption in the groin secondary to PD1 inhibitors.

Hidradenitis Suppurativa.

CASE SUMMARY: A 66-year-old obese (BMI 34) diabetic man, a former smoker who had quit 4 months ago, had a 20-year history of perianal, inguinal, and gluteal hidradenitis suppurativa. He presented to the office with persistent perianal and gluteal inflammation and drainage. He had had various surgical excisions of the affected area over the preceding 10 years. The patient was also following up with dermatology and was previously on doxycycline and infliximab with little improvement in his symptoms. On physical examination of his gluteal and perianal region, he had multiple areas of scarring and draining sinus tracts with significant induration ( and ). The patient underwent extensive unroofing of the sinus tracts and excision of active disease ().(Figure is included in full-text article.)(Figure is included in full-text article.)(Figure is included in full-text article.).

Squamous Cell Carcinoma in Perineal, Perianal, and Gluteal Hidradenitis Suppurativa: Experience in 12 Patients.

BACKGROUND: Few reports describe squamous cell carcinoma (SCC) arising in hidradenitis suppurativa (HS). OBJECTIVE: The 2 objectives were (1) to describe the clinical characteristics, pathologic findings, and postoperative outcomes of SCC in HS and (2) to assess whether human papillomavirus (HPV) is involved in the pathogenesis. MATERIALS AND METHODS: Cases of SCC in HS were identified through institutional medical records (1976-2013) and the Rochester Epidemiology Project. Tumor specimens were assessed for HPV DNA/RNA with in situ hybridization. RESULTS: Twelve patients were identified (11 Caucasians and 9 men). All SCCs involved gluteal, perianal, or perineal skin; 1 patient had, in addition, involvement of the vagina. Surgical excision was performed on all 12 patients, 4 of whom had a colostomy. Mean duration of HS before SCC development was 28.5 years (range, 15-53 years). Mean follow-up was 4.3 years after surgical excision. Seven of 12 patients followed had postoperative SCC recurrence. Squamous cell carcinoma caused death despite wide surgical excision in these 7 patients. Of the remaining 5 patients, 4 are unknown and 1 who did not recur had an in situ SCC (Bowen disease carcinoma). Squamous cell carcinoma was not associated with high-risk or low-risk HPV. CONCLUSION: Invasive SCC arising in HS carries a high risk of death.