Chest tumor response during lung cancer chemotherapy. Computed tomography vs fiberoptic bronchoscopy

Comparison of Symptom Score and Bronchoscopy-Based Assessment With Conventional Computed Tomography-Based Assessment of Response to Chemotherapy in Lung Cancer

Purpose

There is a paucity of literature on symptom score (SS) plus fiberoptic bronchoscopy (FOB) –based response evaluation (RE) to chemotherapy for lung cancer. This study aimed to compare the reliability of RE by SS, chest radiograph (CXR), and FOB with computed tomography (CT) –based assessment (Response Evaluation Criteria in Solid Tumors (RECIST) and WHO criteria) for lung cancer chemotherapy.

Methods

This was a prospective observational study involving treatment-naïve patients with lung cancer planned for chemotherapy, with one or more lesions on FOB and CT. Patients underwent assessment twice by SS, CXR, FOB, and CT (at baseline and after chemotherapy). Six symptoms (dyspnea, cough, chest pain, hemoptysis, anorexia, and weight loss) were noted on visual analog scale. Respiratory symptom burden (RSB) and total symptom burden (TSB) were calculated from the first four and all six symptoms, respectively, as the mean of individual SS. Bronchoscopic findings were recorded as per European Respiratory Society classification for tracheobronchial stenosis. Responses were classified as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD) by each method. For FOB and SS, improvement or worsening by ≥ 20% was taken as PR or PD, respectively, whereas < 20% change was considered SD. Agreements were tested using Cohen’s κ statistic.

Results

All individual SS, RSB, and TSB scores, and the number and distribution of FOB lesions improved significantly after chemotherapy. Individually, CXR and SS had no or minimal agreement with FOB-based and CT-based responses. RECIST and WHO criteria had strong agreement overall (Cohen’s κ = 0.872) and perfect agreement for PD (Cohen’s κ = 1.000). Cohen’s κvalues for FOB-based assessment with RECIST and WHO were 0.324 and 0.349, respectively for overall RE, and 0.462 and 0.501 for differentiating responders (CR and PR) from nonresponders (SD and PD), respectively. Cohen’s κvalues for PD were 0.629 (FOB alone), 0.672 (FOB and RSB), 0.739 (FOB and TSB), and 0.764 (FOB and CXR).

Conclusion

CT-based assessment should remain the reference for objective RE of chemotherapy in lung cancer. A combination of FOB and CXR may be used as a surrogate to diagnose PD if CT is not feasible.

Effect of mitomycin C and vinblastine on FDG uptake of human nonsmall-cell lung cancer xenografts in nude mice

This study was designed to preliminarily evaluate the use of positron emission tomography (PET) with [18F]-2-fluoro-2-deoxy-D-glucose (FDG) for monitoring chemotherapy effects, using a nude-mouse model of human nonsmall-cell lung cancer (NSCLC), the Lu-99 cell line. Tumor-FDG uptakes and volumes were measured after administrating a single dose of mitomycin (MMC) and vinblastine (VLB) and then compared these for a nontherapy group. A significant reduction in tumor volume after either chemotherapy occurred and associated with significantly lower FDG uptake values than the control group (p < 0.001), as early as day 1. These observations suggest that FDG-PET may be useful for noninvasively monitoring the effects of cancer chemotherapy.

Dose-response relationship between probability of pathologic tumor control and glucose metabolic rate measured with FDG PET after preoperative chemoradiotherapy in locally advanced non-small-cell lung cancer

PURPOSE

To determine the dose-response relationship between the probability of tumor control on the basis of pathologic tumor response (pTCP) and the residual metabolic rate of glucose (MRglc) in response to preoperative chemoradiotherapy in locally advanced non-small-cell lung cancer and to define the level of residual MRglc that corresponds to pTCP 50% and pTCP > or = 95%.

METHODS AND MATERIALS

Quantitative dynamic 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography was performed to measure regional MRglc at the primary lesion before and 2 weeks after preoperative chemoradiotherapy in an initial group of 13 patients with locally advanced NSCLC. A simplified kinetic method was developed subsequently from the initial dynamic study and used in the subsequent 16 patients. The preoperative radiotherapy programs consisted of (1) a split course of 42 Gy in 28 fractions within a period of 28 days using a twice-daily treatment schedule for Stage IIIA(N2) NSCLC (n = 18) and (2) standard once-daily radiation schedule of 45-63 Gy in 25-35 fractions during a 5-7-week period (n = 11). The preoperative chemotherapy regimens included two cycles of cisplatin, vinblastine, and 5-fluorouracil (n = 24), cisplatin and etoposide (n = 2), and cisplatin, Taxol, and 5-fluorouracil (n = 3). Patients free of tumor progression after preoperative chemoradiotherapy underwent surgery. The degree of residual MRglc measured 2 weeks after preoperative chemoradiotherapy and 2 weeks before surgery was correlated with the pathologic tumor response. The relationship between MRglc and pTCP was modeled using logistic regression.

RESULTS

Of 32 patients entered into the study, 29 (16 men and 13 women; 30 lesions) were evaluated for the correlation between residual MRglc and pathologic tumor response. Three patients did not participate in the second study because of a steady decline in general condition. The median age was 60 years (range 42-78). One of the 29 patients had two separate lesions, and MRglc was measured in each separately. The tumor histologic types included squamous cell carcinoma (n = 9), adenocarcinoma (n = 13), large cell carcinoma (n = 6), and poorly differentiated carcinoma (n = 2). The extent of the primary and nodal disease was as follows: Stage IIB (T3N0M0), Pancoast tumor (n = 2); Stage IIIA, T2-T3N2M0 (n = 18); Stage IIIB: T1-T3N3M0 (n = 5) and T4N0M0 (n = 2); a second lesion, T1 (n = 1); and localized stump recurrence (n = 2). A pathologically complete response was obtained in 14 (47%) of the 30 lesions. The remaining 16 lesions had residual cancer. The mean baseline value of the maximal MRglc was 0.333 +/- 0.087 micromol/min/g (n = 16), and it was reduced to 0.0957 +/- 0.059 micromol/min/g 2 weeks after chemoradiotherapy (p = 0.011). The correlation between residual MRglc and pTCP was made using an increment value of 0.02 micromol/min/g between the maximal and minimal values of MRglc. A pathologically complete response was obtained in 6 of 6 patients with residual MRglc of < or = 0.050 micromol/min/g, 3 of 4 with < or = 0.070, 4 of 7 with < or = 0.090, 0 of 4 with < or = 0.110, 1 of 3 with < or = 0.130, and 0 of 6 with > or = 0.130 micromol/min/g. The fitted logistic model showed that residual MRglc corresponding to pTCP 50% and pTCP > or = 95% was 0.076 and < or = 0.040 micromol/min/g, respectively.

CONCLUSION

The correlation between the gradient of residual MRglc after chemoradiotherapy and pTCP is an inverse dose-response relationship. Residual MRglc of 0.076 and < or = 0.040 micromol/min/g, representing pTCP 50% and pTCP > or = 95%, respectively, may be useful surrogate markers for the tumor response to radiotherapy or chemoradiotherapy in lung cancer.

[Evaluation of tumor response during chemotherapy of bronchial cancer]

Chemotherapy of lung cancer is still an experimental approach requiring careful evaluation. Tumour response (marker of anticancer activity) is not perfectly correlated to survival (marker of chemotherapy efficacy), but its evaluation remains a milestone inasmuch as reporting a wrong tumour response rate might lead to the rejection of active new treatments. This review deals with the method of tumour response measurements and its use during a chemotherapy protocol. Recommendations drawn from the analysis of the literature are: 1) to assess and classify all lesions which can be identified at the beginning of the treatment; 2) to define the target lesions, mainly the ones which can be bidimensionally measured; 3) to use the World Health Organization recommendations for reporting the overall response; 4) to confirm complete response by negative rebiopsies; 5) to avoid second fiberoptic bronchoscopy to patients with stable or progressive disease on CT-scan, and finally; 6) to assess response quality by evaluating response duration and improvement of quality of life.