Malignant Peripheral Nerve Sheath Tumor post Wide Excision with Multiple Lung Metastases: the Role and Treatment Consideration of RT

Transcription

1 Malignant Peripheral Nerve Sheath Tumor post Wide Excision with Multiple Lung Metastases: the Role and Treatment Consideration of RT Case Number: RT (M) Potential Audiences: Intent Doctor, Oncology Special Nurse, Resident Doctor Purpose: to present a case of malignant peripheral nerve sheath tumor post wide excision with multiple lung metastases; to discuss the role and treatment consideration of radiotherapy Scenario: You are radiotherapy (RT) Intent Doctor/Special Nurse/Resident Doctor, and you are assigned to evaluate the following patient before visiting of your RT attending physician. Please review the following description carefully; your RT attending physician will visit this patient later and discuss with you after your review. Case Presentation: This patient, 林 OO, was consulted under the diagnosis of malignant peripheral never sheath tumor of the right pelvis and the right thigh post wide excision, with multiple lung mets, post incomplete RT, for further RT assessment on 2007/09/17. S: 1. The patient suffered from right lower limb numbness for more than 1 year. 2. In 2007/08, he came to other hospital for further assessment. A mass lesion over the right posterior thigh was noted. Biopsy was performed and pathology reported sarcoma, type unknown. 3. On 2007/08/17, limb-sparing piece-by-piece (non-en-bloc), wide excision for the mass over the right sciatic nerve was performed. Pathology reported malignant peripheral nerve sheath tumor. Multiple lung mets over bilateral lungs were noted. 4. In 2007/09, five fractions of incomplete RT to the tumor bed were done in other hospital. 5. On 2007/09/17, you visited this patient and his family in the ward. Hx: NKA, no major medical history, BPH Review of systems: hoarseness with sometime easy choaking was noted for 1-2 day, no cough, no noted dyspnea. O: 1. ECOG: 1-2, 69 y/o male, sitting on a wheerchair, muscle power of the right lower limb decrease post wide excision 2. PE: a large surgical scar over the right posterior thigh and right pelvis with good healing; numbness over the right lower limb; decrease of muscle power of 4 over the right lower limb 3. ***Pathology in 2007/08, right thigh mass, needle biopsy at other hospital: sarcoma, type unknown. 4. ***Pathology in 2007/08, wide excision, at other hospital: malignant peripheral nerve sheath tumor, grading not mentioned, tumor size more than 5 cm. 5. MRI or CT for the right pelvis and right thigh tumor assessment: not seen at visiting. 6. Images for M disease survey: CXR in 2007/09: multiple lung mets over bilateral lungs with the largest one of 5.5 cm in size; Chest CT in 2007/08 other hospital: multiple lung mets over the bilateral lungs (+), multiple mediastinum LNs with the largest one with size about cm.

2 Key Image(s): Fig. 1. CXR, 2007/09 Fig. 2. CT, 2007/08 Fig. 3. CT, 2007/08

3 Questions & Discussions: (with potential answers) (Please answer the following questions commented from your RT attending physician.) Q1: What are your findings/interpretations for the above key image(s)? Q2: What is your clinical cancer stage, according to the AJCC 2006, for this case? Q3: What is your pathologic cancer stage, according to the AJCC 2006, for this case? Q4: What are your Oncology Diagnosis / Assessments for this case? Q5: What is your Oncology Plan for this case? Q6: What is your Radiotherapy Plan for this case? (Please reply with the following form: Indication/Contraindication, Goal, Target & Volume, Technique, and Dose & Fractionation.)

4 Questions & Discussions: (with potential answers) (Please answer the following questions commented from your RT attending physician.) Q1: What are your findings/interpretations for the above key image(s)? A1: As described in the last attached page. Q2: What is your clinical cancer stage, according to the AJCC 2006, for this case? A2: initial clinical stage unknown Q3: What is your pathologic cancer stage, according to the AJCC 2006, for this case? A3: ptx pnx cm1 Gx, stage IV (2007/09, AJCC 2006) Q4: What are your Oncology Diagnosis / Assessments for this case? A4: 1. Malignant peripheral nerve sheath tumor, Gx, of the right pelvis and the right thigh (right sciatic nerve), initial clinical stage unknown, post non-en-bloc limb-sparing wide excision with partial resection of the right sciatic nerve (2007/08/17, other hospital), post incomplete RT (2007/09, 5 fractions, other hospital), with multiple lung mets and multiple mediastinum LNs, ptx pnx cm1 Gx, stage IV (2007/09, AJCC 2006) 2. The principle of RT to the M1 patients may be tumor-direct limited-field RT. For this patient, however, I will suggest resume RT to the right pelvis and the right thigh tumor bed. The reasons for resume RT are as following ones: first, this patient had factors of high-risk local recurrence, mainly owing to deep-located bulky tumor (more than 5 cm) and non-en-bloc resection in surgical type. Second, if the pelvis local recurrence occurs, the salvage therapies, including surgery or RT, will be very difficult to achieve disease control and QoL maintaning; third, post-op RT has been given incompletely in other clinic for 5 fractions in 2007/09. Q5: What is your Oncology Plan for this case? A5: 1. Suggest current Oncology Plan: (1). salvage chemotherapy and symptoms management. (2). Resume RT to the tumor bed. 2. Anti-neuropathic pain medications, such as Neurontin in conjunction with your current pain control medications (morphine, ultracet, steroid, and others) may be helpful. Q6: What is your Radiotherapy Plan for this case? (Please reply with the following form: Indication/Contraindication, Goal, Target & Volume, Technique, and Dose & Fractionation.) A6: RT Plan may be designed as the following one: (1). Indication: high risk for primary tumor bed recurrence (2). Goal: palliative; prevent major co-morbidities (3). Target & Volume: pelvic and right thigh surgical bed (4). Technique: CT-based 3DCRT or IMRT (5). Dose & Fractionation: cgy in fractions Further Readings & References: NCCN 2009 & Perez 2008 & AJCC 2006 Radiation Oncologist Hon-Yi Lin 2009/03/19

5 Key Image(s): (with marked) Fig. 1. Fig. 1. Multiple lung metastases with different size over the bilateral lungs (as the white arrows). Fig. 2. Fig. 2. Two lung metastases over the bilateral lungs (as the white arrows). Fig. 3. Fig. 3. Two lung mets nodules over the bilateral lungs (as the short white arrows); a small mediastinum LN was also noted (as the long white arrow).