Skeletal muscle metastases on magnetic resonance imaging: analysis of 31 cases. Contemp Oncol (Pozn). 2016;20:242-250. [PMID: 27647989 PMCID: PMC5013688 DOI: 10.5114/wo.2016.61568]

Lessons in clinical reasoning - pitfalls, myths, and pearls: shoulder pain as the first and only manifestation of lung cancer

OBJECTIVES

Lung cancer is the leading cause of cancer-related death and poses significant challenges in diagnosis and management. Although muscle metastases are exceedingly rare and typically not the initial clinical manifestation of neoplastic processes, their recognition is crucial for optimal patient care.

CASE PRESENTATION

We present a case report in which we identify the unique scenario of a 60-year-old man with shoulder pain and a deltoid muscle mass, initially suggestive of an undifferentiated pleomorphic sarcoma. However, further investigations, including radiological findings and muscle biopsy, revealed an unexpected primary lung adenocarcinoma. We performed a systematic literature search to identify the incidence of SMM and reflect on how to improve and build on better diagnosis for entities as atypical as this. This atypical presentation highlights the importance of recognizing and addressing cognitive biases in clinical decision-making, as acknowledging the possibility of uncommon presentations is vital. By embracing a comprehensive approach that combines imaging studies with histopathological confirmation, healthcare providers can ensure accurate prognoses and appropriate management strategies, ultimately improving patient outcomes.

CONCLUSIONS

This case serves as a reminder of the need to remain vigilant, open-minded, and aware of cognitive biases when confronted with uncommon clinical presentations, emphasizing the significance of early recognition and prompt evaluation in achieving optimal patient care.

An Unusual Case of Lung Adenocarcinoma Metastasis to the Tricep Muscle: Four Years Disease-Free After Surgical Resection and Radiotherapy

Lung cancer is one of the leading causes of cancer-related death worldwide. Lung cancer commonly metastasizes to the liver, bone, and brain, but metastasis to skeletal muscles is rare. The development of metastasis in skeletal muscles indicates stage IV disease with a poor prognosis. The most effective treatment strategy is unclear. Palliative radiotherapy is often used to treat skeletal muscle metastases, and patient survival is poor, with an average survival of one year. Here we discuss the case of a 76-year-old female diagnosed with lung adenocarcinoma with metastasis to the trapezius muscle. Initially, she was treated with stereotactic body radiotherapy for stage T1 lung adenocarcinoma. Her follow-up surveillance positron emission tomography (PET) scan in 11 months showed an abnormal focal area of increased activity localizing to the long head of the right triceps muscle. The diagnosis was confirmed with an ultrasound-guided biopsy of the trapezius muscle. Following that, the patient underwent wedge resection of the right middle and upper lobe of the lung and partial right trapezius resection. Afterward, she was given radiation therapy at the tricep resection site. She remained disease-free for four years after excision and radiation therapy.

Skeletal muscle metastases of hepatocellular carcinoma: A case report and literature review

BACKGROUND

The metastasis of liver cancer to skeletal muscle is extremely rare compared to other sites. We herein report a case of rapidly developing skeletal metastases following liver transplantation due to primary liver cancer.

CASE SUMMARY

A 70-year-old male with underlying chronic hepatitis B virus infection was diagnosed with hepatocellular carcinoma (HCC), for which he underwent liver transplantation in 2014. Six years after receiving the transplant, pathological examination confirmed the presence of HCC without vascular invasion. He was admitted to the hospital with a rapidly growing mass on his right thigh. Ultrasound examination revealed a mixed echo mass in the lateral soft tissue of the middle part of the right femur. Magnetic resonance imaging showed heterogeneous iso-signal intensity on T1-weighted images and heterogeneous hyper-intensity on T2-weighted images compared to the surrounding muscles. Pathological examination of the ultrasound-guided needle biopsy specimen revealed that it was similar to the previously detected liver cancer; the diagnosis was metastasis of HCC. Surgical excision was performed. There were no other sites of metastasis, and the patient recovered well after surgery.

CONCLUSION

This report presents a rare case of skeletal metastasis following liver transplantation for HCC. The study suggests a possible role for skeletal muscle metastasis mechanisms, which should be the focus of future research.

EML4-ALK positive lung adenocarcinoma with skeletal muscle metastasis in the right calf which was treatable with lorlatinib after resistance to treatment with alectinib

This report concerns a patient with skeletal muscle metastases due to lung adenocarcinoma harbouring an echinoderm microtubule-associated protein-like-4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement, who was successfully treated with lorlatinib after resistance to alectinib. A right lower lobectomy based on a diagnosis of lung adenocarcinoma was performed on a 77-year-old Japanese woman. After 7 months of surgical resection, a mass in the right calf was observed. A fine-needle aspiration biopsy from the mass was performed and the mass was diagnosed as metastatic adenocarcinoma harbouring EML4-ALK rearrangement. Alectinib was administered for 10 months. Then, administration of lorlatinib, an ALK tyrosine kinase inhibitor classified as third generation, was initiated after resistance to treatment with alectinib. After starting treatment with lorlatinib, the gastrocnemius tumour diminished and has maintained a stable condition. Our case suggests that EML4-ALK positive lung adenocarcinoma is treatable with lorlatinib after resistance to treatment with alectinib.

Skeletal Muscle Metastasis to Vastus Lateralis from a Urothelial Carcinoma: A Case Report and Review of Its Diagnosis and Management

Bladder cancer is a common genitourinary tract malignancy. Urothelial carcinoma is the most frequent type of bladder cancer and it commonly metastasises to lymph nodes, bone, lung and liver by a haematogenous route. Skeletal metastases are very rare and are usually present in patients with advanced metastatic disease. We present an unusual case of a 71-year-old male with a urothelial carcinoma metastasis to the vastus lateralis muscle 3 months following a cystoprostatectomy for muscle invasive bladder cancer.

The role of radiological and hybrid imaging for muscle metastases: a systematic review

AIM OF THE STUDY

Skeletal muscle metastases (SMM) are a rare entity, mainly detected at autopsy. Nevertheless, radiological and nuclear medicine imaging can contribute to the diagnosis with a significant impact on the treatment and prognosis of neoplastic patients. This study aimed to systematically review the features of SMM at imaging considering the primary tumors and the sites of occurrence.

MATERIALS AND METHODS

We conducted a systematic search of three electronic database (i.e., PubMed, Science Direct, and Web of Science) up to May 2019, without any language or time interval restriction. Two reviewers performed the search and selection process, data extraction, and synthesis. We resolved disagreements by consensus and/or involving a third reviewer. The included studies have been classified according to the Oxford Centre for Evidence Based Medicine (CEBM) grading system.

RESULTS

Out of 8598 and 1077 articles respectively for radiological and hybrid imaging, 29 papers were included. According to CEBM, twelve were level 4. Computed tomography (CT) is mainly applied and, despite the existence of CT and magnetic resonance-based classifications, these are rarely used. Positron emission tomography/CT allowed the detection of small and subtle lesion also in the extremities. Muscles of the trunk were mostly affected and mainly respiratory tumors are associated with this type of metastatic spread.

CONCLUSION

Radiological and hybrid imaging allow a precise characterization of SMM. However, a more systematic approach, including also the application of available classification systems, may increase the diagnostic accuracy for this rare type of metastases.

KEY POINTS

• Skeletal muscle metastases have heterogeneous characteristics at imaging but mostly abscess-like features and high metabolic activity are described. • Skeletal muscle metastases mainly affect the muscles of the trunk. • Pulmonary, urological, and gastrointestinal cancers are the most frequent cause of skeletal muscle metastases.