Biochemotherapy for metastatic melanoma with limited central nervous system involvement

Thymoquinone Enhances the Effect of Gamma Knife in B16-F10 Melanoma Through Inhibition of Phosphorylated STAT3

BACKGROUND

Patients with brain metastasis from melanoma have a dismal prognosis with poor survival time. Gamma Knife (GK) is an effective treatment to control brain metastasis from melanoma. Thymoquinone (TQ) has emerged as a potential therapeutic option due to its antiproliferative effects on various cancers. The purpose of the study was to assess the effect of GK on B16-F10 melanoma cells in vitro and intracerebral melanoma in vivo, and its synergistic effect in combination with TQ.

METHODS

The effects of GK and combination treatment of GK and TQ were studied on B16-F10 melanoma cells by evaluating cytotoxicity with an adenosine triphosphate assay, apoptosis by acridine orange staining, and genotoxicity by comet assay. Western blot analysis was performed to investigate the expression of STAT3, p-STAT3 (Tyr705), JAK2, p-JAK2, caspase-3, Bax, Bcl-2, survivin, and β-actin. Expression of inflammatory cytokines was assessed by enzyme-linked immunosorbent assay. GK alone and in combination with TQ was assessed in an established intracerebral melanoma tumor in mice.

RESULTS

The effects of GK on cytotoxicity, genotoxicity, and apoptosis were enhanced by TQ in B16-F10 melanoma cells. GK induced apoptosis through inhibition of p-STAT3 expression, which in turn regulated pro- and antiapoptotic proteins such as caspase-3, Bax, Bcl-2, and survivin. Adding TQ to GK irradiation further enhanced this apoptotic effect of GK irradiation. GK was shown to reduce the levels of tumor-related inflammatory cytokines in B16-F10 melanoma cells. This effect was more pronounced when TQ was added to GK irradiation. GK with 15 Gy increased the survival of mice with intracerebral melanoma compared with untreated mice. However, despite the additive effect of TQ in addition to GK irradiation on B16-F10 melanoma cells in vitro, TQ did not add any significant survival benefit to GK treatment in mice with intracerebral melanoma.

CONCLUSIONS

Our findings suggest that TQ would be a potential therapeutic agent in addition to GK to enhance the antitumor effect of irradiation. Further studies are required to support our findings.

Cerebral melanoma metastases: a critical review on diagnostic methods and therapeutic options

Malignant melanoma represents the third most common cause for cerebral metastases after breast and lung cancer. Central nervous system (CNS) metastases occur in 10 to 40% of patients with melanoma. Most of the symptoms of CNS melanoma metastases are unspecific and depend on localization of the lesion. All patients with new neurological signs and a previous primary melanoma lesion must be investigated. Although primary diagnosis may rely on computed tomography scan, magnetic resonance images are usually used in order to study more precisely the characteristics of the lesions in and to embase the surgical plan. Other possible complementary exams are: positron emission tomography, iofetamine cintilography, immunohistochemistry of liquor, monoclonal antibody immunocytology, optical coherence tomography, and transcriptase-polymerase chain reaction. Treatment procedures are indicated based on patient clinical status, presence of unique or multiple lesions, and family agreement. Often surgery, radiosurgery, whole brain radiotherapy, and chemotherapy are combined in order to obtain longer remissions and optimal symptom relieve. Corticoids may be also useful in those cases that present with remarkable peritumoral edema and important mass effect. Despite of the advance in therapeutic options, prognosis for patients with melanoma brain metastases remains poor with a median survival time of six months after diagnosis.

Clinical variables and primary tumor characteristics predictive of the development of melanoma brain metastases and post-brain metastases survival

BACKGROUND

Melanoma patients who develop brain metastases (B-Met) have limited survival and are excluded from most clinical trials. In the current study, the authors attempted to identify primary tumor characteristics and clinical features predictive of B-Met development and post-B-Met survival.

METHODS

A prospectively accrued cohort of 900 melanoma patients was studied to identify clinicopathologic features of primary melanoma (eg, thickness, ulceration, mitotic index, and lymphovascular invasion) that are predictive of B-Met development and survival after a diagnosis of B-Met. Associations between clinical variables present at the time of B-Met diagnosis (eg, extracranial metastases, B-Met location, and the presence of neurological symptoms) and post-B-Met survival were also assessed. Univariate associations were analyzed using Kaplan-Meier survival analysis, and the effect of independent predictors was assessed using multivariate Cox proportional hazards regression analysis.

RESULTS

Of the 900 melanoma patients studied, 89 (10%) developed B-Met. Ulceration and site of the primary tumor on the head and neck were found to be independent predictors of B-Met development on multivariate analysis (P = .001 and P = .003, respectively). Clinical variables found to be predictive of post-B-Met survival on multivariate analysis included the presence of neurological symptoms (P = .008) and extracranial metastases (P = .04). Ulceration was the only primary tumor characteristic that remained a significant predictor of post-B-Met survival on multivariate analysis (P = .04).

CONCLUSIONS

Primary tumor ulceration was found to be the strongest predictor of B-Met development and remained an independent predictor of decreased post-B-Met survival in a multivariate analysis inclusive of primary tumor characteristics and clinical variables. The results of the current study suggest that patients with ulcerated primary tumors should be prospectively studied to determine whether heightened surveillance for B-Met can improve clinical outcome.

Treatment options for brain metastases from melanoma

Brain metastases are a common complication of metastatic malignant melanoma, conferring an exceedingly poor prognosis. Diagnosis of brain metastasis often has significant implications for duration and quality of life, and management can be difficult due to rapid progression of disease and resistance to conventional therapies. This review focuses primarily on the published evidence for treatment modalities for brain metastases from melanoma, emerging technologies and outlines future directions for research. In summary, external-beam radiation alone appears effective in palliating symptoms. Surgical management of solitary or acutely symptomatic lesions appears to alleviate symptoms and provide the possibility of local control of disease. Stereotactic radiosurgery is an increasingly utilized technique for patients with a limited number of metastases and presents a less-invasive alternative to craniotomy. Chemotherapy alone is relatively ineffective, although combined chemotherapy with external-beam radiation is being investigated. Future directions include combined modality therapy, the incorporation of novel agents and careful consideration of the structure of clinical trials for this disease.

Metastatic melanoma: is biochemotherapy the future?

Current treatment options in metastatic melanoma are of limited efficacy. Achievement of durable responses with biological agents, and the possibility to complement the higher response rate of chemotherapy and combined chemotherapy by prolonged duration of responses, led to development of biochemotherapy. Although a clear improvement in response rate (40-60% OR) resulted in some studies of the combined modality, several phase III studies had mixed results on the duration of survival. Various timeframes between the administration of chemotherapy and biologics have been tested, ranging between concurrent biochemotherapy, 1 d (immediately sequential), and up to 3 wk (long sequence or alternating). An analysis of the trend of responses and survival versus the duration of the chemobiotherapy sequence showed that, as the timeframe between chemo and bio components increases, the overall survival, survival of complete responders, and survival of partial responders appear to increase, but the effect is only present for the chemo-bio, and not for the bio-chemo sequence. Because there is no current explanation for this observation, it appears possible that the interaction between components of biochemotherapy results in a double effect: an increase in the immediate response reflected in the OR, CR, PR on one side, and an increase in survival on the other side. An analysis of mechanisms involved in the response leads us hypothesize that macrophage activation, as measured by the neopterin levels, may correlate with the survival of patients undergoing biochemotherapy, while the generation of nitric oxide, acting synergistically with chemotherapy in producing tumor cell killing, may be reflected in the overall response rate seen with the biochemotherapy combinations.

A phase II study of biochemotherapy for advanced melanoma incorporating temozolomide, decrescendo interleukin-2 and GM-CSF

Metastatic malignant melanoma remains a very difficult disease to treat. Previous phase II studies using biochemotherapy (combination of platinum-containing chemotherapy with IL-2 and IFNalpha) have shown response rates of about 50%. However, a site of frequent relapse is in the central nervous system (CNS). Temozolomide is an oral alkylating agent that has equivalent activity to dacarbazine, but it has the advantage of CNS penetration. We report the results of a phase II study using a novel biochemotherapy regimen containing temozolomide, cisplatin, decrescendo IL-2, IFNalpha, and GM-CSF in the treatment of stage IV melanoma. Seventy-one patients with histologically confirmed metastatic melanoma were enrolled between June 1998 and October 1999. Prior chemotherapy or IL-2 was not permitted. The median age was 54 years (range 22-72). Twenty-one patients (30%) had a history of treated brain metastases. Patients received temozolomide 150 mg/m2 orally days 1-5, cisplatin 30 mg/m2 IV days 1-3, IFNalpha 5 MU/m2 SQ on days 1-5, and IL-2 was administered in a decrescendo fashion according to the following schedule: day 1: 18 MU/m2 continuous IV infusion over 6 hours; day 2: 18 MU/m2 continuous IV infusion over 12 hours; day 3: 9 MU/m2 subcutaneously q12 hours; day 4: 4.5 MU/m2 subcutaneously x 1. Patients were also given GM-CSF 250 microg subcutaneously days 6-25. The cycles were repeated every 4 weeks. Partial responses were seen in 10 of the 71 patients (14%) with a median duration of response of 9.4 months. There were no complete responses. The median survival for all patients was 8.6 months. Further studies of this novel biochemotherapy regimen are not indicated. Other schedules that incorporate temozolomide and/or GM-CSF and further studies to define the optimal method of delivering IL-2 should be pursued.

Overview of anal cancer for the surgeon

Cancers of the anal canal represent a diverse group of pathology and require a multidisciplinary approach for treatment. For the most common anal canal cancer, anal SCC, the primary therapy is CMT with systemic chemotherapy and radiation. The surgeon plays a key role in the diagnosis and follow-up after treatment, with surgical intervention reserved for residual or recurrent disease. The overall prognosis for this disease is favorable. For anal adenocarcinoma, aggressive surgical resection remains the mainstay of therapy, with radiation therapy and chemotherapy used to aid in local disease control and for treatment of metastatic disease. A high rate of distant failure in this disease is responsible for the poor long-term prognosis. Anorectal melanoma has a high rate of distant failure and a poor overall survival rate. Surgical intervention is focused on local disease control with preservation of sphincter function. The biggest improvements in survival for this disease will come with more effective systemic therapy.

Management of brain metastases in patients with melanoma

PURPOSE OF REVIEW

Melanoma is the third most common metastatic brain tumor in the United States and is a major cause of morbidity and mortality. The development of more effective therapies for melanoma brain metastases is a major unmet clinical need and is summarized in this review.

RECENT FINDINGS

Management strategies include symptomatic treatment with corticosteroids and anticonvulsants, and definitive therapy in the form of whole-brain radiation therapy, surgical resection, stereotactic radiosurgery, and systemic therapy. The data on whole-brain radiation therapy show little impact on survival, but there is evidence that it may improve neurologic deficits. Surgery may provide a survival advantage in combination with whole-brain radiation therapy in the management of a single brain melanoma metastasis, compared with whole-brain radiation therapy alone. Stereotactic radiosurgery may offer a survival advantage (in a select group of patients with limited disease) when used alone or in combination with whole-brain radiation therapy, compared with whole-brain radiation therapy alone. Fotemustine, temozolomide, and thalidomide are three agents with high central nervous system penetration that are being actively investigated as part of systemic therapy.

SUMMARY

The currently available therapeutic options offer palliative relief of symptoms in most patients and a survival advantage in selected patients with melanoma and brain metastases. An urgent need exists to further define these treatments in the context of randomized trials, several of which are under way in the United States and abroad.