A large thigh mass: a blood clot or a rare skeletal muscle metastasis from renal cell carcinoma

Skeletal Muscle Metastasis From Renal Cell Carcinoma: A Case Series and Literature Review

Objectives

Skeletal muscle metastasis (SMM) from renal cell carcinoma (RCC) has been rarely reported. This case series was performed to increase the clinicians' understanding of its clinical features and treatments.

Methods

We evaluated the clinical presentations, diagnoses, and treatments of 2 patients with SMM from RCC in our hospital and 39 cases reported in the literature.

Results

Among the 41 patients, 4 (9.76%) were women and 37 (90.24%) were all men. The average age was 60.5 ± 12.6 years old (range from 7 to 81). The size of tumors varied from 1 to 28 cm, and the metastatic sites of 6 (14.63%) cases were in the heads, 20 (48.78%) in the limbs, 9 (21.95%) in the trunks, 3 (7.32%) in the buttock, and the other 3 (7.32%) were multiple sites. The mean of intervals between the RCC and the discovery of the first SMM was 73.61 months. More than half of the patients (25, 60.98%) were diagnosed by MRI and 25 (60.98%) patients performed a biopsy of the mass to establish the diagnosis. Finally, 30 (73.17%) cases performed mass excision. Then the adjuvant therapy was performed in 18 patients including immunotherapy, radiotherapy, chemotherapy, and targeted therapy. The median follow-up after SMM was 9 months (P25, P75: 5, 23), in which the longest survival time of patients with SMM of RCC was 8 years while the shortest was only 3 months.

Conclusion

The characteristic clinical feature of SMM from RCC is asymptomatic masses or swelling with a long history which can be preoperative suspiciously diagnosed by MRI. The rapid biopsy of suspected lesions, determination of other metastasis sites, resection of metastasis, and systematic treatment are the recommended treatments of it.

Delayed Presentation of Metastatic Renal Cell Carcinoma as an Arteriovenous Malformation Mimicking Vascular Tumour of the Forearm

INTRODUCTION

The development of metastatic renal cell carcinoma (RCC) many years after a nephrectomy is not common but has been reported. A metastasis appearing as a hypervascular tumour, mimicking an arteriovenous malformation (AVM), is a highly unusual phenomenon, with a biopsy required for diagnostic confirmation. Surgery is an option for a solitary metastatic lesion amenable to complete excision, with proven survival benefits. However, widespread metastatic disease carries a very poor prognosis, and is best treated with systemic agents such as anti-angiogenic drugs or tyrosine kinase inhibitors.

REPORT

A 58 year old man developed an AVM mimicking a vascular tumour within his left brachioradialis muscle 10 years after a nephrectomy for RCC. Ultrasound and magnetic resonance imaging did not reveal any suspicious features of the vascular lesion.The lesion was successfully removed surgically, and was later proven histopathologically to be metastatic RCC. Further imaging showed widespread metastatic disease, and the patient survived only 15 months after receiving tyrosine kinase inhibitor therapy.

DISCUSSION

This case report aims to highlight a few important points: RCC metastases may be hypervascular, mimicking an AVM. A long disease free interval does not necessarily exclude recurrence or metastasis, as in this case, therefore long term surveillance is recommended. A high index of suspicion must be maintained to avoid delay in treatment, and biopsy of any suspicious lesion for histological examination is mandatory, albeit after many years of cancer remission. Whole body imaging with computed tomography or positron emission tomography computed tomography may detect clinically occult recurrence or metastases, and is important to guide further treatment.

Rectal adenocarcinoma presenting with thigh muscle metastasis as the only metastatic site

Rectal carcinoma with metastasis to skeletal muscle is a rare finding. According to literature review, 17 cases of skeletal muscle metastasis from colorectal carcinoma have been documented where only six cases were rectal carcinomas.We discuss a case of a middle-aged man with a known history of high-grade mucinous adenocarcinoma of the rectum, status post abdominoperineal resection followed by adjuvant radiotherapy and chemotherapy. During the planned chemotherapy course, a right proximal thigh subcutaneous mass was incidentally found which on subsequent biopsy proved to be metastatic from rectal primary site. On subsequent 18F-FDG (Fluorodeoxyglucose) positron emission tomography (PET)/CT scan after completion of chemotherapy for the purpose of treatment response evaluation, only FDG-avid lesion was residual right proximal thigh metastatic mass without involvement of other common sites, such as liver and lung. In this case, the 18F-FDG-PET/CT scan was able to exclude additional metastatic sites and also evaluate the patient's treatment response.

Metastatic renal clear cell carcinoma to the rectum, lungs, ilium, and lymph nodes: A case report

BACKGROUND

Renal cell carcinoma metastasizing to rectum is very rare, and the unusual metastatic sites should be paid attention to during the follow-up of renal cell carcinoma.

CASE SUMMARY

We describe a case of a 65-year-old male who was diagnosed with metastatic renal cell carcinoma to rectum 10 years after the right radical nephrectomy. Histopathology and immunohistochemical examinations contribute to making differential diagnosis between rectal metastasis of renal cell carcinoma and primary rectal clear cell carcinoma. Positron emission tomography-computed tomography with fluorodeoxyglucose shows hypermetabolic activity in upper rectum and other sites of metastasis at the same time.

CONCLUSION

Possibility of unusual metastatic sites of renal cell carcinoma such as rectum indeed exists, which should not be ignored in the surveillance after resection of the primary tumor.

Skeletal Muscle Metastases and Inferior Vena Cava Involvement in a Patient with Clear Cell Renal Cell Carcinoma and Sarcomatoid Differentiation

Introduction: Renal cell carcinoma has a propensity to propagate into the renal vein and inferior vena cava. A small percentage has distant metastasis at presentation. Pulmonary, hepatic, cerebral and bone metastases are common, but skeletal muscle involvement is rare.

Case presentation: We present the case of a 51-year-old patient complaining of right flank pain, gross hematuria and a painful left laterothoracic mass. Preoperative examination revealed a tumor in the inferior pole of the right kidney, thrombosis of the right renal vein that extended into the inferior vena cava and a left laterothoracic tumor. We decided on a preoperative digital subtraction angiography and selected embolization of the laterothoracic mass. We performed right radical nephrectomy with vena cava thrombus excision and excision of the left laterothoracic tumor. The pathological examination revealed a clear cell renal carcinoma with sarcomatoid differentiation of the right kidney. Metastases with the above features were noticed in the right adrenal gland and in the skeletal muscle of the chest wall.

Conclusions: The surgical resection of large renal tumors with associated thrombus within the inferior vena cava is challenging to any surgeon. The preoperative embolization of the metastatic tumor is helpful in the reduction of pain and intraoperative blood loss.

Tumors Involving Skin, Soft Tissue and Skeletal Muscle: Benign, Primary Malignant or Metastatic?

BACKGROUND

Metastatic cancer with invasion of skin, soft tissue and skeletal muscle is not common. Examples presenting as soft tissue masses could sometimes lead to misdiagnosis with delayed or inappropriate management. The purpose of current study was to investigate clinical characteristics in the involvement of metastatic cancer.

MATERIALS AND METHODS

A total of 1,097 patients complaining of skin or soft tissue masses and/or lesions were retrospectively reviewed from January 2012 to June 2013. Tumors involving skin, soft tissue and skeletal muscle of head and neck, chest wall, abdominal wall, pelvic region, back, upper and lower extremities were included in the study.

RESULTS

Fifty-seven (5.2%) patients were recognized as having malignancies on histopathological examination. The most common involvement of malignancy was basal cell carcinoma, followed by cutaneous squamous cell carcinoma, sarcoma and melanoma. The most common anatomical location in skin and soft tissue malignancies was head and neck (52.6% of the malignancies). Four (0.36%) of the malignant group were identified as metastatic cancer with the primary cancer source from lung, liver and tonsil and the most common site was upper extremities. One of them unexpectedly expired during the operation of metastatic tumor excision at the scalp.

CONCLUSIONS

Discrimination between benign and malignant soft tissue tumors is crucial. Performance of imaging study could assist in the differential diagnosis and the pre-operative risk evaluation of metastatic tumors involving skin, soft tissue and skeletal muscle.