This report presents the cases of two patients affected by NSCLC, metastatic to the right thigh muscle and left mandible. Both patients were treated with RT to the involved area, in addition to systemic chemotherapy. Few data are reported about metastases to muscle from primary lung cancer. Moreover, metastases to soft tissue can be misdiagnosed histologically as primary soft tissue sarcomas. The treatment and prognosis for a metastatic neoplasm of the soft tissue and a primary soft tissue sarcoma are different
. Various mechanical factors, such as tissue blood flow, arterial pressure, muscle contraction and trauma, have been described as possible causes for rare metastases to muscle
. Often these metastases are diagnosed at different time intervals from the discovery of the primary tumor, being discovered in some cases more than five years later. The most commonly involved sites are the muscles of the trunk, particularly the paraspinal and psoas muscles
. In our first patient’s case, however, the region of interest was the lower extremity. Many cases of skeletal muscle metastases described in the literature showed clinical symptoms and signs, such as in our patient with edema and phlebitis. Although several reports underline that these events are not common, a recent study by Haygood et al. explores the epidemiology of metastases to skeletal muscle and their detection by PET/CT, concluding that skeletal muscle metastases are not unusual and the most common source is lung cancer
. The increasing use of PET/CT has recently led to diagnosis of unsuspected distant/solitary metastases at rare locations, including the colon and extra-ocular muscles
. There is no agreement on the optimal therapeutic strategy for muscle metastases from NSCLC, although several therapeutic options can be offered to patients such as radiation therapy, chemotherapy or surgical excision. Unfortunately, the outcome remains poor and the prognosis of these patients with muscle metastasis from NSCLC remains doubtful
. In this report, with regard to our first patient, the use of radiation therapy on muscle metastasis can be considered as a potentially successful treatment option, giving patients the possibility to avoid an aggressive treatment such as surgery and reducing the possible side effects.
Likewise, the clinical presentation of mandibular metastases are similar to common conditions such as toothache or, less frequently, temporo-mandibular joint pain, osteomyelitis, or trigeminal neuralgia
. Consequently the diagnostic and therapeutic investigation of these patients may be difficult. Metastases to the jaw involve the mandible in 80 percent of cases, and the most common locations for oral metastasis are the molar and pre-molar regions of the mandibular bone. Most studies of oral metastatic disease indicate its predilection for the posterior mandible
[12, 13] because of its rich blood supply in active areas of hematopoiesis; conversely, in our study, the anterior of the mandible was involved. Metastatic bone lesions are generally determined after the detection of the primary tumor; they may be the first symptom of metastatic disease in approximately 30 percent of cases. Data from the literature reveal that autopsies detected muscle metastases in about 17 percent of patients
. In the second case report, we described the clinical history of a patient affected by metastasis to the mandible that disclosed the presence of a silent primary lung cancer. Pruckmayer et al. evaluated 763 patients retrospectively who suffered from jaw pain. They concluded that a selected subgroup of individuals, specifically patients with a history of cancer or those not responding to conventional management, should undergo specific investigations such as bone scans to rule out a neoplastic cause
Although radical surgery treatment of the solitary metastatic bone lesion or of muscle metastasis in patients who are oligometastatic and plurimetastatic could be considered as therapeutic options, palliative radiation therapy was offered to our patients obtaining good control of tumor size and pain. Both patients are alive, with follow-up of five and 18 months. Palliative radiation therapy is one of the major contributors to the care of patients with oncological issues, and also, in selected cases, a second radiation therapy treatment is feasible, well tolerated and offers the possibility of symptomatic relief. Our treatments were carefully chosen to maintain the quality of life of our patients in both cases, and we obtained good results without serious side effects although it should be noted the prognosis in metastatic NSCLC remains poor.