PET Detection of Solitary Distant Skeletal Muscle Metastasis of Esophageal Adenocarcinoma

Subcutaneous and Muscle Metastases From Rectal Adenocarcinoma on 18 F-FDG PET/CT Imaging

ABSTRACT

A 50-year-old man with T4 N2 M1 poorly differentiated adenocarcinoma of the rectum underwent neoadjuvant chemotherapy, surgical resection, and subsequent chemotherapy. Six months after surgery, routine follow-up CT revealed the presence of abdominal wall subcutaneous nodules associated with bilateral pulmonary and renal nodules, indicating metastases. Further 18 F-FDG PET/CT scan revealed a high number of subcutaneous and muscle metastases. Metastasis of rectal adenocarcinoma to subcutaneous tissue or skeletal muscle is considered rare.

Skeletal muscle metastases of the trunk and pelvis: focus on ultrasound, CT findings, and clinical manifestations

Objective:

To describe the ultrasound, CT findings, and clinical manifestations of pathologically confirmed skeletal muscle metastases involving trunk and pelvis.

Methods:

71 patients with 71 skeletal muscle metastases of the trunk and pelvis, pathologically proven by ultrasound-guided biopsy, were included in the study, and ultrasound findings were reviewed. CT findings were reviewed for 60 patients who underwent post-contrast CT obtained prior to biopsy, which included skeletal muscle metastases. Medical records, including the type of primary malignancy, presence of coexisting distant metastasis, and method of detection that led to referral for biopsy, were reviewed.

Results:

Most skeletal muscle metastases were hypoechoic (98.6%) with well-defined margins (85.9%), round-to-oval (47.9%), or lobulated (42.2%) with intralesional vascularity (64.8%). Typical CT findings included abscess-like lesions with rim enhancement (53.3%) or round-to-oval lesions with homogeneous enhancement (40.0%). The most common primary malignancy was lung cancer (49.3%), followed by gastrointestinal cancer (7.0%). Distant metastases other than muscle metastases were found in 84.5% of patients, and coexisting skeletal muscle metastases were found in 47.9%. CT was the most common detection method for metastases (57.8%), being more common than positron emission tomography-CT (22.5%).

Conclusion:

The current study describes the typical imaging findings of skeletal muscle metastases of the trunk and pelvis in patients with advanced cancer. CT may play an important role in the early detection of skeletal muscle metastases, and our results may aid radiologists in their diagnosis.

Advances in knowledge:

1. Skeletal muscle metastases of the trunk and pelvis demonstrate typical imaging findings on ultrasound and CT. 2. CT may aid in the early detection of skeletal muscle metastases, which are among the rarest, and our results may aid radiologists in their diagnosis.

Soft-Tissue Metastases From Esophageal Cancer

BACKGROUND

Metastatic carcinoma to skeletal muscle and/or subcutaneous fat is a rare event. Only 27 cases of esophageal cancer to soft tissue have been described in the English-language literature.

PURPOSE

Our goal was to describe the prevalence and clinical characteristics of soft-tissue metastasis among patients with primary esophageal cancer at a single institution.

METHODS

We performed a retrospective review of all patients with primary esophageal cancer. Data points analyzed included histologic subtype, anatomic location, metastasis pattern, treatment, and survival. Kaplan-Meier curves were used to estimate survival time, and log-rank tests were used for comparisons. For all analyses, P < 0.05 was considered significant.

RESULTS

Of 1341 patients with primary esophageal cancer, 25 (1.9%) had metastases to soft tissue. Soft-tissue metastases were diagnosed at a median age of 64 years, a median 9.6 months after esophageal cancer diagnosis. Adenocarcinoma was the predominant histopathological type, and soft-tissue metastasis was most common in the lower extremity. Local intervention was used for 10 symptomatic patients with favorable prognoses. Chemotherapy was the only treatment modality in 18 patients. Median survival time after diagnosis of soft-tissue metastasis was 8.9 months and was longer in patients with metastasis in soft tissue only (24.6 months, P = 0.007) and in those who received local intervention (11.1 months vs those who did not, P = 0.020).

CONCLUSION

We estimate the prevalence of soft-tissue metastasis to be 1.9% among patients with esophageal cancer. Local intervention may be beneficial for patients in otherwise good health with symptomatic soft-tissue lesions.

A long-term survival case after surgical resection of skeletal muscle metastasis following esophagectomy for squamous cell carcinoma of the esophagus

Cases of skeletal muscle metastasis of esophageal carcinoma are very rare, with few reports of long-term survival. We report a case of long-term survival after surgical resection of skeletal muscle metastasis. A 56-year-old man with advanced esophageal cancer and early gastric cancer underwent thoracoscopic esophagectomy, 2-field lymph node dissection, partial gastrectomy and gastric tube reconstruction. Six months later, cervical lymph node metastasis and mediastinal lymph node recurrence were found. Therefore, the patient underwent cervical lymph node dissection and adjuvant chemoradiotherapy. Two years and 3 months after the esophagectomy, a muscle metastasis was found in the left shoulder, and he underwent tumor dissection, followed by adjuvant chemotherapy for a year. There has been no sign of recurrence since, even 13 years after the esophagectomy. We believe our aggressive surgical treatment might have led to long-term survival.

Esophageal Cancer Metastases to Unexpected Sites: A Systematic Review. Gastroenterol Res Pract. 2017;2017:1657310. [PMID: 28659974 PMCID: PMC5474273 DOI: 10.1155/2017/1657310]

The most common pattern of esophageal cancer metastases (ECM) is to the lymph nodes, lung, liver, bones, adrenal glands, and brain. On the other hand, unexpected metastasis (UM) spread to uncommon sites has increasingly reported and consequently affected the pathway of diagnosis, staging, and management. Using the PubMed database, a systematic search of the following headings “Esophageal” and “Metastasis” or “Metastases” was performed, 10049 articles were identified, and the articles were included if they demonstrated unexpected ECM. 84% of cases were men with an average age of 60.7 years. EC was located in the lower third in 65%. Two-thirds of the UM originated from the lower esophagus, and the two major histological types were adenocarcinoma 40% and squamous cell carcinoma 60%. Metastases were disseminated toward five main anatomical sites: the head and neck (42%), thoracic (17%), abdomen and pelvis (25%), extremities (9%), and multiple skin and muscle metastases (7%). The EC metastases were found to be synchronous 42% and metachronous 58%, isolated in 53.5% and multiple in 46.5%. The overall survival rate was 10.2 months. Since distant metastases are responsible for most EC-related deaths, understanding of ECM dissemination patterns needs more extensive studies. These critical data are the cornerstone of optimal cancer approach and treatment.

Skeletal muscle metastasis from signet ring cell esophageal adenocarcinoma

Symptomatic skeletal muscle metastasis from esophageal adenocarcinoma is rare. Here we report the case of a 49-year-old man who presented with right thigh pain, and was found to have symptomatic psoas muscle metastasis as the presentation of esophageal adenocarcinoma. The primary tumor was notable for signet ring cells (SRC), a poor prognostic indicator as well as a predictor of biologic aggressiveness. The patient passed away within 1 month of diagnosis due to disease progression, supporting the aggressiveness of such SRC esophageal lesions. Lastly, a literature review reveals a differential pattern of metastatic spread between esophageal adenocarcinomas and squamous cell carcinomas as regards muscle metastases. Skeletal muscle metastases are more likely to be due to esophageal adenocarcinoma, whereas myocardial metastases are almost exclusively due to esophageal squamous cell carcinoma (ESCC). These differences may represent an example of the 'seed and soil' hypothesis of metastasis.

Infiltrative pattern of carcinomatosis in extremity muscles on MRI

Carcinomas can cause an unusual, infiltrative pattern of metastatic carcinoma in extremity muscles on MRI. To assess this pattern, reports of MRI exams of 907 consecutive patients with a diagnosis of carcinoma were reviewed retrospectively to identify those that mentioned muscle metastasis or myositis in an extremity. Thirty-six (4%) of those reports described muscle metastasis (n=18) or myositis (n=18); based on medical record review and imaging follow-up, 17 cases represented metastases. Metastases manifested as an infiltrative carcinomatosis pattern in five patients, resulted from primary esophageal or gastric adenocarcinomas, and often were misdiagnosed as myositis.

Primary esophageal adenocarcinoma with distant metastasis to the skeletal muscle

Hematogenous metastasis of esophageal adenocarcinoma to the skeletal muscle is uncommon. We report a rare case of esophageal adenocarcinoma with metastasis to the skeletal muscle. During pretherapeutic examination, a painful mass was detected in the left thigh of a 49-year-old man. Endoscopic biopsy identified poorly differentiated, advanced esophageal adenocarcinoma. Computed tomography (CT) revealed wall thickening in the distal esophagus. Two enlarged lymph nodes were detected--the middle thoracic paraesophageal lymph node in the mediastinum and the right cardiac lymph node. (18)F-fluorodeoxyglucose (FDG) positron emission tomography demonstrated left thigh metastasis, which had not been detected by CT 3 weeks previously, with increased accumulation of FDG. Therefore, ultrasound-guided core-needle biopsy was performed. Histologic and immunohistochemical findings supported a diagnosis of poorly differentiated adenocarcinoma. The final diagnosis was primary esophageal adenocarcinoma with distant metastasis to the skeletal (left thigh) muscle. The rate of disease progression in this case emphasizes the malignant potential of esophageal adenocarcinoma. A few cases of skeletal metastasis from advanced esophageal adenocarcinoma have been previously reported. However, rapid metastasis to a distant skeletal muscle with no other hematogenous metastasis is quite rare. Early detection and rapid treatment are especially important in cases of esophageal adenocarcinoma.

PET/CT imaging of skeletal muscle metastases

BACKGROUND

Skeletal muscle metastases (SMM) are very rare because of complex resistance of the musculature to metastatic invasion. Previously, positron emission tomography (PET) imaging of SMM has been reported only in few reports. A systematic analysis of SMM features in PET/CT has not been performed before.

PURPOSE

To study PET/CT findings of SMM in a larger group of patients with known malignancies and to determine PET/CT patterns of SMM in different primary tumors.

MATERIAL AND METHODS

Between January 2009 and December 2011 581 patients with lung cancer were investigated by PET with 18 F-fluordeoxyglucose (FDG PET) and computed tomography (CT) at the Center of Fusion Imaging, Halle. In five patients SMM were identified. Furthermore, PubMed database was screened for muscle metastases. Only articles containing SUV of SMM were considered in the study. Twenty-one articles with 33 patients could be included in this meta-analysis from the literature.

RESULTS

At our center the prevalence of SMM was 0.9%. Our analysis comprised 38 patients with 67 muscle metastases. All identified SMM presented as intramuscular focal abnormal activity with SUV ranging from 2.4 to 25.9, median SUV 7.8. The median size of the muscle metastases was 2.5 cm (range, 0.6-6.5 cm). There were no significant differences between SUV and size of SMM arising from lung cancer, renal cell carcinoma, and esophageal cancer. Also, there was no correlation between SUV and size of SMM (r = 0.101, P = 0.558) and between SUV of SMM and primary tumors (r = 0.138, P = 0.686). In nine (23.7%) of the 38 patients, the identified SMM were isolated distant metastases or isolated tumor recurrence.

CONCLUSION

SMM manifested on PET/CT as focal hypermetabolic intramuscular areas with different SUV. There were no significant differences between SUV or size of the identified SMM in esophageal cancer, renal cell carcinoma, and lung cancer.

Metastases of esophageal carcinoma to skeletal muscle: Single center experience

Metastases of esophageal carcinoma to the skeletal muscle are rare, but the incidence may be increasing because of better diagnosis resulting from widespread use of positron emission tomography/computed tomography (PET/CT). A cohort of 205 patients with esophageal carcinoma treated at our center who had PET/CT between 2006 and 2010 was retrospectively evaluated for the presence of skeletal muscle metastases. Four patients had skeletal muscle metastases of esophageal carcinoma, including two patients with squamous cell carcinoma. In another patient with squamous cell carcinoma of the esophagus and synchronous skeletal muscle metastases, muscle metastases were subsequently shown to be related to second primary pancreatic adenocarcinoma. In all cases, skeletal muscle metastases were the first manifestation of systemic disease. In three patients palliation was obtained with the combination of external beam radiation therapy, systemic chemotherapy or surgical resection. Skeletal muscle metastases are a rare complication of esophageal carcinoma.

Skeletal muscle metastases: a three-part study of a not-so-rare entity

OBJECTIVE

Our purposes were to explore the epidemiology of metastases to skeletal muscle and their detection on fused positron emission tomography and computed tomography.

MATERIALS AND METHODS

We evaluated the epidemiology of skeletal muscle metastases in the literature and among cases from our hospital and studied the prevalence and appearance of skeletal muscle metastases among 433 patients undergoing fused positron emission tomography and computed tomography for non-small-cell lung cancer.

RESULTS

We found 264 cases of skeletal muscle metastases in 151 articles. Mean age was 57.8 years with 67% men. At our hospital we studied 70 cases. Mean patient age was 55.7 years with 63% men. The most common source was lung cancer, and the most common site of involvement was the muscles of the trunk. Among our lung cancer patients undergoing fused positron emission tomography and computed tomography, we found 7 (1.6%) with skeletal muscle metastases. In only one of these seven patients was the metastasis first discovered by another imaging modality. In one patient discovery of the metastasis at fused positron emission tomography and computed tomography changed management.

CONCLUSION

Skeletal muscle metastases are not rare. They may be more apparent at fused positron emission tomography and computed tomography than at other staging examinations, particularly contrast-enhanced CT scanning. Radiologists need to be alert to their presence when interpreting staging examinations in cancer patients.

Intramuscular metastases on FDG PET-CT: a review of the literature

OBJECTIVE

Intramuscular metastases (IM) are both rare and difficult to detect using routine anatomical computed tomography (CT) imaging. However, since the introduction of 18F-fluoro-deoxy-glucose (FDG) PET-CT, the number of detected IM has increased. We review the available literature to illustrate the relevance of these findings for staging and patient management.

METHODS

In a review of the literature, we found one series and 33 case reports of IM shown on FDG PET-CT. No cases were reported before 2005. Furthermore, we present a patient with nonsmall cell lung cancer and a solitary distant metastasis in the left musculus infraspinatus that was not detected on diagnostic CT, but was found on FDG PET-CT.

RESULTS

For a total of 39 recorded cases of IM, we found that FDG PET-CT had a significant impact on patient management in at least 51% of cases. Where reported, lesions were either isodense or hypodense on CT compared with the surrounding muscle tissue. The lesions that were also analyzed with MRI showed heterogeneous intensity. Five out of 39 patients had metastases in the extraocular muscles of one or both orbits.

CONCLUSION

FDG PET-CT appears to be a sensitive tool for detecting IM, with important impact on management in many cases.

Giant temporalis muscle metastasis of esophageal carcinoma

Temporalis muscle metastasis of a tumor is a rare condition. Basaloid squamous cell carcinoma is an uncommon variant of squamous cell carcinoma, which often occurs in the aerodigestive tract. To the best of our knowledge, there have been no previous reports dealing with temporalis muscle metastasis from esophageal carcinoma in the literature.

Histopathological outcome of 597 isolated soft tissue tumors suspected of soft tissue sarcoma: A single-center 12-year experience

BACKGROUND

The aim of this present report was to analyze the patients referred to us with the presumptive diagnosis of soft tissue sarcoma (STS).

METHODS

We reviewed all patients referred to us with suspected soft tissue sarcoma (STS) of the extremities or trunk over a 12-year period.

RESULTS

We treated 597 patients with soft tissue tumors. Open biopsy revealed soft tissue sarcoma in 318 cases, benign mesenchymal tumor in 124 cases and isolated metastases (ISTM) from carcinomas in 98 patients; other pathologies were found in 57 patients. The primary carcinomas were lung cancer in 26 patients, breast cancer in 19 patients, renal carcinoma in 16 patients, carcinoma of the esophagus in 12 patients, colonic carcinoma in 5 patients, thyroid gland cancer in 6 patients, and in 14 patients carcinoma of unknown primary was diagnosed.

CONCLUSIONS

In our collective with soft tissue tumor, 50% of the patients had the diagnosis of soft tissue sarcoma, 20% presented with a metastasis of carcinoma and 20% had a benign tumor. Referring to our results, in patients with the presumptive diagnosis of soft tissue sarcomas, soft tissue metastasis of a primary carcinoma was unexpectedly common, indicating that greater consideration should be given to this differential diagnosis.

Integrated CT-PET imaging of esophageal cancer: unexpected and unusual distribution of distant organ metastases

CT-PET imaging is being increasingly used for the initial staging, assessment of treatment response, and follow-up of patients with esophageal carcinoma, primarily because of its superior detection of distant metastases compared to conventional methods. Our recent experience has shown that metastases from esophageal cancer can occur in unusual locations and have an unexpected presentation. Recognition of the distribution and appearance of esophageal metastases is important for optimal image interpretation in order to avoid confusion with more benign disease. This article reviews the location and appearance of metastases detected by CT-PET imaging in patients with esophageal cancer either at presentation or after preoperative or definitive chemoradiation therapy.

Multiple metastases to skeletal muscle from carcinoma of the esophagus detected by FDG PET-CT imaging

A 67-year-old woman was treated with neoadjuvant chemotherapy, esophagectomy, and subsequent radiotherapy for T3N1 poorly differentiated adenocarcinoma of the esophagus. Five months after surgery, a routine follow-up CT demonstrated a 1.2-cm soft tissue mass in the posterior mediastinum suspicious for local recurrence. An FDG-PET/CT study confirmed tumor in the posterior mediastinum and also showed focal areas of increased tracer uptake within several muscles. Skeletal muscle is one of the most unusual sites of metastatic disease, although it is probable that the more frequent use of FDG-PET imaging will lead to an increase in the detection of such lesions.