Adenocarcinoma of the appendix occurring in a patient treated with paclitaxel for locally advanced esophageal cancer

Paclitaxel has been linked with a number of immunosuppressive effects such as decreased numbers and activity of dendritic cells, NK-cells and monocytes, which may in turn lead to defective T-cell activation. In addition, this agent was shown to cause mitotic arrest resembling high-grade dysplasia throughout the gastrointestinal tract, including the appendix. We have previously documented a series of lung cancer patients who developed pre-malignant colonic polyps and/or colon cancer either during or weeks following chemotherapy with paclitaxel, suggesting a potential role of this agent in their pathogenesis. We describe herein a patient who developed adenocarcinoma of the appendix five months after paclitaxel therapy for a locally advanced lower esophageal cancer. Although the cancer of the appendix was in early stage, it was poorly differentiated and showed lymphovascular invasion. The context, timeline and existing experience suggest that this second cancer was triggered by a pre-existing insult, conceivably delivered by paclitaxel.

Accelerated Premalignant Polyposis and Second Colon Cancers: Incriminating Immunosuppression, Radiotherapy, and Systemic Chemotherapy Agents

BACKGROUND

Cancer survivors are known to be at increased risk for second primary cancers. In addition, immunosuppression and previous cancer treatments such as radiotherapy and systemic chemotherapy are linked with increased risk of both colonic adenomas and adenocarcinomas.

AIM

We performed a systematic review searching for manuscripts discussing second colon cancers, accelerated polyposis, immunosuppression, radiation, and chemotherapy. We sought to identify a link between immunosuppression and increased risks specific to premalignant polyposis and second colon cancers.

FINDINGS

We identified multiple studies demonstrating associations between radiotherapy, systemic chemotherapy, and immunosuppression with a higher propensity for second colon adenomas and adenocarcinomas. When compared to the general population, these risks were more profound and the rate at which these second malignancies developed was significantly increased.

CONCLUSIONS

We believe that timing for colonoscopic surveillance in these patients should be different from the general population in order to identify promptly these rapidly progressive neoplasms. Screening for second malignancies should be considered early after remission of the primary cancer is documented, especially when a prolonged survival or a cure is anticipated. We also recommend consideration be given to increasing the frequency of colonoscopy in these cohorts. Future studies are required in order to establish the optimal time interval for surveillance colonoscopy in these high-risk individuals.

Paclitaxel enhances antibody-dependent cell-mediated cytotoxicity of trastuzumab by rapid recruitment of natural killer cells in HER2-positive breast cancer

INTRODUCTION

An important mechanism by which trastuzumab inhibits the growth of human epidermal growth factor receptor 2 (HER2)-positive breast cancer cells is the activation of a host tumor response via antibody-dependent cell-mediated cytotoxicity (ADCC). Although paclitaxel has a synergistic effect in combination with trastuzumab, whether ADCC is enhanced by paclitaxel is not known. In the present study we examined whether adding paclitaxel to trastuzumab enhances ADCC and also investigated the kinetics of effector cells in ADCC.

MATERIALS AND METHODS

The subjects were 20 patients with HER2-positive breast cancer: 9 received the combination of trastuzumab (4 mg/kg as a loading dose and 2 mg/kg weekly) and paclitaxel (80 mg/m(2) weekly) and 19 received monotherapy with trastuzumab. In blood samples (mononuclear cells) obtained before and 10 minutes after administration of chemotherapy, ADCC and the number of effector cells, including natural killer (NK) cells, monocytes, and CD64+ cells, were compared in each case. The ADCC was analyzed with a (51)Cr releasing assay using the SK-BR-3 cell line, and the fractions of NK cells (both CD16+ [FcγRIII] and CD56+) and CD64+ (FcγRI) cells were analyzed with flow cytometry.

RESULTS

The mean ADCC level increased 20% after trastuzumab monotherapy and 126% (p<0.05) after combination therapy with trastuzumab and paclitaxel. All 9 patients receiving combination therapy had increased ADCC levels. The number of NK cells increased 51% after trastuzumab monotherapy and 112% (p<0.05) after combination therapy. No significant changes were found in monocytes (39% increase) or CD64+ cells (53% increase) after trastuzumab monotherapy, but monocytes decreased 40% (p<0.05) and CD64+ cells decreased 24% after combination therapy.

CONCLUSIONS

Adding paclitaxel to trastuzumab significantly enhances ADCC, with levels twice as great as with trastuzumab monotherapy, through a rapid recruitment of NK cells. This finding suggests that the combination of trastuzumab and paclitaxel has a stronger-than-expected synergistic effect in HER2-positive breast cancer.

Immune alterations and immunotherapy prospects in head and neck cancer

INTRODUCTION

Several literature sources have suggested that subjects with head and neck squamous cell carcinoma (HNSCC) display significant abnormalities of immunocompetent cells and cytokine secretion. Serious side effects and only a limited success with traditional therapies in HNSCC dictate the need for newer therapies.

AREAS COVERED

This article comprehensively reviews the immune system alterations in HNSCC and the rationale behind various experimental immunotherapies, aiming at keeping this disease under control. Relevant publications were identified through the PubMed database search. The ongoing clinical trials regarding experimental immunotherapy agents in HNSCC were accessed at www.clinicaltrials.gov . The obtained information was thoroughly analyzed and systematized.

EXPERT OPINION

Important and severe immune defects including T-cell dysfunction, cytokine alterations and antigen presentation defects are present in patients with HNSCC. In addition, tumor microenvironment was shown to play a critical role in the HNSCC progression. These discoveries have triggered a growing interest in immunotherapy as a potential treatment strategy for HNSCC. Effective immunotherapy could avoid the toxic side effects plaguing the current management of HNSCC. It is also hoped that immunotherapy will have long-lasting effects due to induction of immunologic memory. Promising directions include nonspecific immune stimulation, targeting specific HNSCC tumor antigens and therapeutic vaccines among others. These new agents may expand the existing therapy options for HNSCC in future.