Effectiveness and risk of second primary malignancies after radiotherapy in major salivary gland carcinomas: A retrospective study using SEER database

OBJECTIVE

To investigate the effectiveness of radiotherapy and its association with second primary malignancies (SPMs) risk in major salivary gland carcinomas (MSGCs) patients.

METHODS

Cohort 1 included 7274 surgically treated MSGC patients from the Surveillance, Epidemiology, and End Results database, assessing the effectiveness of radiotherapy. Cohort 2 (n = 4213) comprised patients with ≥5-year survival in Cohort 1 to study SPMs.

RESULTS

Radiotherapy decreased overall survival in MSGCs patients, but improved it in high-grade MSGCs. Cumulative SPMs incidences at 25 years were 16.5% in the radiotherapy (RT) group compared to 14.5% in the non-radiotherapy (NRT) group. For second head and neck carcinomas (SHNCs), incidences were 3.4% in RT versus 1.6% in NRT. Radiotherapy increased the relative risks of tumors, particularly SHNCs (RR = 1.78). The 10-year OS rates of SHNCs after radiotherapy were significantly lower.

CONCLUSION

Radiotherapy improves survival in advanced-stage MSGCs but increases the risk of developing SPMs, particularly SHNCs.

Prognostic Assessment and Risk Stratification in Patients With Postoperative Major Salivary Acinar Cell Carcinoma

OBJECTIVE

To investigate the clinicopathological features and prognosis of postoperative major salivary acinar cell carcinoma (MSACC) and develop a prognostic model.

STUDY DESIGN

Retrospective cohort analysis of a public database.

SETTING

Patients with MSACC were identified from the Surveillance, Epidemiology, and End Results database (1975-2019).

METHODS

Overall survival (OS) was evaluated using Kaplan-Meier curves and a log-rank test. Univariate and multivariate Cox analyses were performed to explore independent prognostic factors. The prognostic model was constructed using screened variables and further visualized with a nomogram and web calculator, and assessed by concordance index, the area under the curve, calibration curve, and decision-making curve analysis.

RESULTS

An upward trend in the incidence of MSACC was observed throughout the study period. A total of 1398 patients were enrolled (training cohort: 978; validation cohort: 420), and the 5- and 10-year OS rates were 97.7% and 81.6%, respectively. Age, marital status, sex, histological grade, T stage, and lymph node status were identified as prognostic factors for OS. A novel nomogram was developed and showed excellent discrimination and clinical applicability. Additionally, a web calculator was designed to dynamically predict patient survival. Based on the nomogram-based score, a risk stratification system was constructed to distinguish patients with different risks. The OS of high-risk patients was significantly lower than that of the low-risk subgroup.

CONCLUSION

Long-term survival in postoperative MSACC was influenced by 6 prognostic factors. The proposed model enables individualized survival prediction and risk stratification, prompting us to be vigilant in high-risk subgroups and consider timely adjustment of subsequent treatment.

Second primary cancer after major salivary gland carcinoma

BACKGROUND

We investigated the risk of second primary cancers after major salivary gland carcinoma in Finland, with a population of 5.5 million.

METHODS

Nationwide cancer registry data were used to identify patients with major salivary gland carcinoma diagnosed between 1953 and 2014. Standardized incidence ratios (SIRs) were estimated to compare their second primary cancer risk with the respective site-specific cancer risk in the general population.

RESULTS

There were 1727 patients with major salivary gland carcinomas and 222 second primary cancers had been diagnosed in these patients (SIR 1.43). The risk was increased for cancers of the thyroid (SIR 5.12), breast (SIR 1.63), respiratory organs (SIR 1.63), male genital organs (SIR 1.48), melanoma of the skin (SIR 3.35), and nonmelanoma skin cancer (SIR 2.50). The risk was high during the first 5 years and after 20 years of diagnosis.

CONCLUSION

Second primary cancers can occur among patients with major salivary gland carcinoma even after a long time period. This needs to be recognized in the follow-up of these patients.

Complementary role of the Memorial Sloan Kettering Cancer Center nomogram to the American Joint Committee on Cancer system for the prediction of relapse of major salivary gland carcinoma after surgery

BACKGROUND

The purpose of this study was to test the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram in predicting recurrence risk of major salivary gland carcinoma in an Asian cohort.

METHODS

We retrospectively enrolled 149 patients who had undergone intended curative resections for major salivary gland carcinoma between 2007 and 2012. The performance of the MSKCC nomogram and the American Joint Committee on Cancer (AJCC) seventh staging system in predicting recurrence risk was compared.

RESULTS

The MSKCC nomogram and the AJCC staging system both accurately predicted the 5-year recurrence probabilities, with the concordance index (c-index = 0.82; 95% confidence interval [CI], 0.75-0.89 vs c-index, 0.77; 95% CI, 0.68-0.87; p = .45) in patients with major salivary gland carcinomas after curative surgeries. Comparing to the actual observed events, the calibration plot indicated that the MSKCC nomogram accurately estimated the recurrence in low-risk groups but tended to overestimate in high-risk groups. When using the MSKCC nomogram to predict the 5-year recurrence-free probability in each AJCC stage, the prediction was very good for patients with AJCC stages I and II disease (c-index = 0.92 and 0.90, respectively) and modest for those of AJCC stages III and IVa (c-index = 0.51 and 0.62, respectively).

CONCLUSION

The MSKCC nomogram and the AJCC staging system each had its value in predicting recurrence of major salivary gland cancers. When using the MSKCC nomogram to predict the 5-year recurrence-free probability in each AJCC stage, the MSKCC nomogram was more accurate in predicting recurrence risks in those patients with AJCC stage I and II diseases than those with late-stage diseases. © 2017 Wiley Periodicals, Inc. Head Neck 39: 860-867, 2017.

Lymph node density is a prognostic factor in patients with major salivary gland carcinoma

Lymph node density (LND) has been reported to be a significant predictor of survival in patients with oral and other carcinomas exhibiting positive lymph nodes. The present study investigated whether the LND is associated with overall survival in subjects with major salivary gland carcinoma. A total of 78 patients newly diagnosed with major salivary gland carcinoma underwent primary tumor resection and neck dissection without preoperative treatment. Of these 78 patients, 32 with pathologically positive lymph nodes were enrolled in the present study. The LND was calculated as the ratio of the number of positive lymph nodes to the number of total lymph nodes. The survival rate was analyzed according to the Kaplan-Meier method. A univariate survival analysis was performed using the log-rank test, and a multivariate survival analysis was performed using the Cox proportional hazards model. An LND of ≥0.38 was found to significantly correlate with a shorter overall survival time in univariate analysis (P=0.017). In multivariate survival analysis, after adjusting for anatomical location (parotid gland/others), an LND of ≥0.38 was identified to be associated with a significantly shorter overall survival time. These results suggest that the LND functions as a prognostic factor in cases of major salivary gland carcinoma.

Prognostic relevance of cell proliferation in major salivary gland carcinomas

Several proliferation markers, such as DNA ploidy, Ki67, MiB1 and proliferating cell nuclear antigen have been shown to correlate with clinical course and prognosis in several epithelial tumours and lymphomas. In the present study, the prognostic relevance of these markers was evaluated in major salivary gland carcinomas. A sample of 36 cases out of 85 patients submitted to surgery for major salivary gland carcinomas at our institution between 1987 and 1997 were studied. The sample comprised 8 adenoid-cystic carcinomas, 6 ductal carcinomas, 11 mucoepidermoid carcinomas and 11 acinic cell carcinomas. Follow-up ranged from 1 to 12 years (mean 6.2). In some patients, DNA ploidy (euploid or aneuploid) was studied by flow cytometry. In others, proliferation activity was studied by means of monoclonal antibody MiB1, identifying cells in the proliferative cycle. In some patients, both techniques were used. Follow-up was related to these indices, TNM and stage. Even if ploidy suggested a favourable outcome in diploid cancer (13 favourable vs. 2 unfavourable) and poor outcome in aneuploid cancer (4 favourable vs. 5 unfavourable), the difference was not statistically significant with p = 0.06 in Fisher's exact test. Instead, the proliferative tumour cell fraction, evaluated by MiB1, was statistically correlated with prognosis. Comparing survival curves by Log rank Test it yielded p = 0.007 using an MiB1 cut-off of 5. Applying a cut-off of 20 yielded p = 0.001. Of particular interest were MiB1 values in acinic cell carcinomas for which grading is challenging and lacks consensus. In our group of acinic cell carcinomas, survival correlated with values of MiB1 > or < 15 with p = 0.009 in Log rank test. In conclusion, despite a trend towards correlation between ploidy and prognosis, the present study yielded p = 0.06, whereas the proliferative fraction assessed by MiB1 was significantly correlated with outcomes. Indeed, "growth fraction" in acinic cell carcinomas may stratify different classes of risk.