Lymph node involvement in macroscopic medullary thyroid carcinoma

Omission of lateral lymph node dissection in medullary thyroid cancer without a desmoplastic stromal reaction

BACKGROUND

Medullary thyroid cancer can be subdivided during surgery into tumours with or without a desmoplastic stromal reaction (DSR). DSR positivity is regarded as a sign of disposition to metastasize. The aim of this study was to analyse whether lateral lymph node dissection can be omitted in patients with DSR-negative tumours.

METHODS

This was a retrospective cohort study of a prospectively maintained database of patients with medullary thyroid cancer treated using a standardized protocol, and subdivided into DSR-negative and -positive groups based on the results of intraoperative frozen-section analysis. Patients in the DSR-negative group did not undergo lateral lymph node dissection. Long-term clinical and biochemical follow-up data were collected, and baseline parameters and histopathological characteristics were compared between groups.

RESULTS

The study included 360 patients. In the DSR-negative group (17.8 per cent of all tumours) no patient had lateral lymph node or distant metastases at diagnosis or during follow-up, and all patients were biochemically cured. In the DSR-positive group (82.2 per cent of all tumours), lymph node and distant metastases were present in 31.4 and 6.4 per cent of patients respectively. DSR-negative tumours were more often stage pT1a and were significantly smaller. The median levels of basal calcitonin and carcinoembryonic antigen were significantly lower in the DSR-negative group, although when adjusted for T category both showed widely overlapping ranges.

CONCLUSION

Lymph node surgery may be individualized in medullary thyroid cancer based on intraoperative analysis of the DSR. Patients with DSR-negative tumours do not require lateral lymph node dissection.

Medullary thyroid cancer outcomes in patients with undetectable versus normalized postoperative calcitonin levels

BACKGROUND

Calcitonin (Ct) is a sensitive diagnostic biomarker and one of the most important prognostic factors in medullary thyroid cancer (MTC). This study aimed to evaluate progression-free survival and recurrence rates of MTC associated with undetectable compared with normalized serum Ct levels after surgery.

METHODS

This retrospective observational study included patients operated for MTC at the Digestive and Endocrine Surgery Department of Lyon Sud Hospital Centre between 2000 and 2019. Clinical and pathological factors were correlated with postoperative Ct concentrations. Undetectable and normalized Ct concentrations were defined as below 2 pg/ml and 2-10 pg/ml respectively.

RESULTS

Overall, 176 patients were treated for MTC, and 127 were considered biochemically cured after surgery. Of these, 24 and 103 had normalized and undetectable Ct concentrations respectively. Patients with Ct level normalization had a 25 per cent risk of disease recurrence, compared with 3 per cent in patients with undetectable Ct levels after surgery. The presence of metastasis in two or more compartments was predictive of failure to achieve undetectable Ct concentrations after surgery and an increased risk of recurrence.

CONCLUSION

Among patients with biochemically cured MTC, those with undetectable or normalized Ct concentrations after surgery had different risks of recurrence. Simply assessing postoperative Ct normalization can be falsely reassuring, and long-term follow-up is needed.

Large sporadic thyroid medullary carcinomas: predictive factors for lymph node involvement

Lymph node involvement (LNI) is one of the most important prognostic factors for poor survival in medullary thyroid carcinoma (MTC). At diagnosis, LNI is found in over 50% of sporadic MTCs, and especially in large tumours. Cervical lymph node dissection is therefore mandatory during MTC surgery. However, some large tumours (responsible for high preoperative basal calcitonin levels) are found to lack LNI, and can be cured definitely. Preoperative detection of these particular tumours might spare patients from undergoing extensive cervical dissection. The objective of the present retrospective study of a series of large sporadic MTCs was to identify clinical, biological and pathological factors that were predictive of LNI. Consecutive cases of large, sporadic MTCs (measuring at least 1 cm in diameter) were retrieved and reviewed. The levels of several mature microRNAs (miRs) in paraffin-embedded samples were assessed using qPCR. Of the 54 MTCs, 26 had LNI and 28 were pN0. Relative to pN0 patients, patients with LNI had a significant higher preoperative basal calcitonin level (p = 0.0074) and a greater prevalence of infiltrative margins (p < 0.0001), lymphovascular invasion (p = 0.0004), extrathyroidal extension (p < 0.0001), a higher pT stage (p = 0.0003) and more abundant desmoplastic stroma (p = 0.0006). Tumour expression levels of miR-21 (p = 0.0008) and miR-183 (p = 0.0096) were higher in the LNI group. The abundance of desmoplastic stroma (p = 0.007) and the miR-21 expression level (p = 0.0026) were independent prognostic factors for LNI. The abundance of desmoplastic stroma and high levels of miR-21 expression were strong indicators of LNI, and may thus help the surgeon to choose the extent of cervical lymph node dissection for large, sporadic MTCs with no preoperatively obvious LNI.

Intraoperative high-dose calcium stimulation test in patients with sporadic medullary thyroid carcinoma is highly accurate in predicting lateral neck metastases

BACKGROUND

Intraoperative measurement of calcitonin is not highly accurate in predicting the completeness of the operative resection after total thyroidectomy combined with central neck dissection (TT-CND) in patients with medullary thyroid carcinoma (MTC). We evaluated whether an intraoperative, high-dose calcium stimulation test (IO-CST) after TT-CND can predict lateral neck involvement.

METHODS

Eleven patients who underwent primary operation for sporadic MTC were included. High-dose (25 mg/kg) calcium gluconate was administered after TT-CND with calcitonin measured at 2, 5, and 10 minutes after the calcium gluconate infusion.

RESULTS

There were 2 males and 9 females (mean age, 51 years; range, 18-88). Three patients showed lateral neck metastases. At a mean follow-up of 7.0 months (range, 2-10), 1 patient showed distant metastases and 1 a slightly increased calcitonin level. After IO-CST, serum calcitonin increased in all the 3 patients with lateral neck metastases, and it remained unchanged or decreased in the other patients without lateral neck metastases. Percent variation of serum calcitonin after IO-CST was 92% in patients with lateral neck metastases and -3.1 ± 4.9% in patients without lateral neck metastases.

CONCLUSION

Calcitonin measurement after IO-CST in patients with sporadic MTC can be highly accurate in predicting lateral neck nodes involvement. These results could represent a stimulus toward the development of a quick calcitonin assay.

Tumor protein p53-induced nuclear protein (TP53INP1) expression in medullary thyroid carcinoma: a molecular guide to the optimal extent of surgery?

BACKGROUND

Medullary thyroid cancer (MTC) is characterized by early regional lymph node metastasis, the presence of which represents a critical obstacle to cure. At present no molecular markers have been successfully integrated into the clinical care of sporadic MTC. The present study was designed to evaluate TP53INP1 expression in MTC and to assess its ability to guide the surgeon to the optimal extent of surgery performed with curative intent.

METHODS

Thirty-eight patients with sporadic MTC were evaluated. TP53INP1 immunoexpression was studied on embedded paraffin material and on cytological smears.

RESULTS

TP53INP1 was expressed in normal C cells, in C-cell hyperplasia, and in 57.9% of MTC. It was possible to identify two groups of MTC according to the proportion of TP53INP1 expressing tumor cells: group 1 from 0% to <50% and group 2 from 50% to 100% of positive cells. Patients with a decreased expression of TP53INP1 (group 1) had a lower rate of nodal metastasis (18.8% versus 63.4% in group 2; P = 0.009), with only minimal lymph node involvement per N1 patient (2.7% of positive lymph nodes versus 22.9%; P < 0.001) and better outcomes (100% of biochemical cure versus 55.5%; P < 0.001). Patients with distant metastases were only observed in group 2. Cytological samples exhibit similar results to their embedded counterparts.

CONCLUSIONS

TP53INP1 immunoexpression appears to be a clinical predictor of lymph node metastasis in MTC. The evaluation of TP53INP1 expression may guide the extent of lymph node dissection in the clinically node-negative neck. These findings require prospective validation.

Detection of medullary thyroid cancer: a focus on serum calcitonin levels

Medullary thyroid cancer (MTC) is a neuroendocrine tumor derived from the C cells of the thyroid. C cells are responsible for the production of calcitonin, a sensitive and specific marker for MTC. Early detection of MTC is essential; overall survival from MTC is related to patient age, stage of disease and extent of surgical resection. Elevated preoperative serum calcitonin levels have been shown to predict the likelihood of biochemical remission postoperatively. The use of routine serum calcitonin measurements as a screening measure for MTC in patients with thyroid nodules has been advocated in Europe. To date, routine calcitonin measurement has not been widely practiced in the USA; a recent cost-effectiveness analysis suggests routine serum calcitonin measurements in patients with thyroid nodules may be comparable to other widely accepted screening programs.

Desmoplasia in medullary thyroid carcinoma: a reliable indicator of metastatic potential

AIMS

To evaluate the reliability of desmoplasia as a reproducible morphological parameter indicating the metastatic potential of medullary thyroid carcinoma (MTC).

METHODS AND RESULTS

One hundred and twenty cases of MTC of the Medical University of Vienna, Austria and 76 cases from the School of Medicine of Marseille, France were analysed for the presence of desmoplastic stroma reaction by four endocrine pathologists. Intra- and interobserver concordance was assessed. The Austrian cases were also analysed for various morphological parameters. Intra- and interobserver concordance were highly significant with a kappa value of 0.883 for intra-observer reliability and 0.837, 0.79 and 0.758, respectively, when pathologists N.N., C.D.M. and K.W.S. reviewed the Austrian cases. The cases from France were reviewed by C.D.M. and K.K. with a kappa value of 0.759. None of the cases that were categorized as desmoplasia negative by any of the investigators showed lymph node metastasis. No other distinct morphological characteristics could be assigned to the MTCs without desmoplasia.

CONCLUSIONS

Our data indicate desmoplasia to be a reliable and highly reproducible parameter with regard to lymph node metastatic potential.

Increased risk of lymph node metastasis in multifocal hereditary and sporadic medullary thyroid cancer

BACKGROUND

In sporadic and hereditary medullary thyroid cancer, tumor multifocality may constitute an independent risk factor of lymph node metastasis on top of primary tumor size when the diameter of the largest primary tumor is the same.

METHODS

Included in this institutional cohort study were 232 consecutive patients operated on at our institution for hitherto untreated medullary thyroid cancer. Associations of clinicopathologic variables with lymph node metastasis were investigated simultaneously using multivariate Cox regression analysis.

RESULTS

On univariate analysis, multifocal cancers developed lymph node metastases significantly more often (p < or = 0.005) than unifocal cancers, in both the sporadic (90% vs. 41%) and the hereditary setting (48% vs. 14%). On multivariate Cox regression analysis on lymph node metastasis as a function of primary tumor diameter, only multifocal (vs. unifocal) tumor growth was significantly associated with lymph node metastasis (odds ratio [OR] = 2.5; p = 0.01). When multifocal growth was removed as an independent variable from the Cox model, heredity became the only significant predictor (OR = 3.1; p < 0.0001).

CONCLUSION

The excess risk of lymph node metastasis of 34%-49% in multifocal medullary thyroid cancer seems to be caused by concurrent smaller thyroid cancers. A diagnosis of more than one medullary thyroid cancer signifies a higher risk of lymph node metastasis, warranting systematic lymph node dissection.

Hypereosinophilia as the presentation of metastatic medullary thyroid carcinoma: a remarkable event

Hypereosinophilic syndrome is a rare disorder characterized by persistent eosinophilia combined with organ system dysfunction. This report is of a 37-year-old man who had eosinophilia, periodic fever, weight loss, and generalized bone pain. A small nodule in left lobe of thyroid was detected in his physical examination. The patient underwent surgery and histopathological study, which confirmed that the patient had medullary carcinoma of thyroid. The patient died 6 months after the surgery. Eosinophilia is more commonly seen with benign conditions. However, less frequent but malignant etiologies always should be contemplated.

Cancer médullaire de la thyroïde

Medullary thyroid carcinoma (MTC) is developed from thyroid C cells that secrete calcitonin (CT). MTC represents 5-10% of thyroid cancers with a 1-2% incidence in nodular thyroid diseases. Diagnosis is usually made by a solitary nodule often associated to nodal metastasis and confirmed by a high basal CT level which represents its biological marker. MTC may present as a sporadic form and in about 30% of case as a familial form as a part of multiple endocrine neoplasia syndrome, an hereditary dominant inherited disease related to germline mutation of the proto-oncogene RET. Both biological (CT) and genetic (RET) markers allows the optimal diagnosis and treatment of MTC; the former allows screening and early diagnosis of MTC by routinely CT measurements in nodular thyroid diseases that make the adequate and complete surgery required to be performed. The former leads to diagnose familial MTC and to identify at risk subjects in whom early or prophylactic surgery may be performed. Treatment of MTC is based on the complete surgical resection: total thyroidectomy associated to central and laterocervical nodal dissection. For locally advanced or metastatic MTC, complete cervical surgery is required and needs to be associated to other systemic treatments: as chemotherapy is not very efficient, radioimmunotherapy and RET target gene therapy (mainly tyrosine kinase inhibitors) appears as possible valuable therapeutic options for the future. Prognosis of MTC is mainly related to both the stage of the disease and the extend of the initial surgery. Ten-year survival is about 80% when the patients are not surgically cured and reaches 95% when the biological marker CT is normalized after surgery.

Evidence-based approach to the management of sporadic medullary thyroid carcinoma

Medullary thyroid carcinoma (MTC) is a rare malignancy of the thyroid C cells. It occurs in hereditary (25% of cases) and sporadic (75%) forms. Sporadic MTCs frequently metastasize to cervical lymph nodes. Thorough surgical extirpation of the primary tumor and nodal metastases by compartment-oriented resection has been the mainstay of treatment (level IV evidence). Surgical resection of residual and recurrent disease is effective in reducing calcitonin levels and controlling complications of central neck disease (level IV evidence). Radioactive iodine, external beam radiation therapy, and conventional chemotherapy have not been effective. Newer systemic treatments, with agents that target abnormal RET proteins hold promise and are being tested in clinical trials for patients with metastatic disease.

Lymphadenektomie beim Schilddrüsen- und Nebenschilddrüsenkarzinom

In general, primary surgery of thyroid carcinoma should consist of total thyroidectomy and lymph node dissection of the cervicocentral compartment. Exceptions are cases of papillary microcarcinoma and prophylactic surgery due to multiple type 2A endocrine neoplasia. Lymph node dissection beyond the cervicocentral compartment also should be compartment-oriented. It is generally indicated if lymph node metastases have been proven. Concerning clinically proven medullary thyroid carcinoma, bilateral cervicolateral lymph node dissection is generally indicated, since lymph node metastases may be missed preoperatively but are often found histologically. In patients with parathyroid carcinoma, en bloc ipsilateral cervicocentral lymph node dissection should be performed in addition to parathyroidectomy and hemithyroidectomy. Lymph node dissection should always be performed systematically, since lymph node metastases may be missed both clinically and by imaging techniques.

Prognosis of medullary thyroid carcinoma: demographic, clinical, and pathologic predictors of survival in 1252 cases

BACKGROUND

Medullary thyroid cancer (MTC) is a rare cancer. There is a relative paucity of data over the last decade with regard to the prognosis of these patients. Therefore, the authors used the population-based Surveillance, Epidemiology, and End Results (SEER) registry to update what to their knowledge is one of the largest series of patients with MTC reported to date.

METHODS

All patients with a diagnosis of MTC with active follow-up in the SEER database from 1973 to 2002 were included. Univariate and multivariate regression analyses were used to assess the associations between demographic, clinical, and pathologic characteristics of patients and survival.

RESULTS

A total of 1252 patients with MTC were identified over 29 years of follow-up. In all, 87% of patients were white and 60% were female, with a mean age of 50 years. Although many variables were significant on univariate analysis, SEER stage and age at diagnosis were found to be the strongest predictors of survival in the multivariate analysis. Prognosis was poor in patients with advanced disease (hazards ratio [HR], 4.47), or those age >65 years (HR, 6.55). Patients who underwent surgery fared better than those who did not. Overall, 51% of patients had less than the currently recommended treatment guidelines for MTC. Adjuvant radiation therapy was found to be independently associated with a decreased survival (HR, 1.65).

CONCLUSIONS

Stage of disease and age at diagnosis were found to be the strongest predictors of survival for patients with MTC. To the authors' knowledge there has been no change in stage at diagnosis or a significant improvement in survival noted over the last 30 years. Many patients underwent surgery that was deemed less than optimal for stage of disease.

NEW ERA: PROPHYLACTIC SURGERY FOR PATIENTS WITH MULTIPLE ENDOCRINE NEOPLASIA-2A

BACKGROUND

The surgical management of patients with multiple endocrine neoplasia-2A (MEN-2A) continues to evolve with specific genotype-phenotype correlations allowing for a more tailored approach. In this study, we report the surgical management of one of the largest MEN-2A families with a rearranged during transfection (RET) codon 804 mutation.

METHOD

This is a cohort study comprising all at-risk kindred within a single known MEN-2A family. Prophylactic total thyroidectomy with lymph node dissection was recommended to all mutation carriers aged 5 years and older.

RESULTS

There were a total of 48 at-risk individuals in the MEN-2A kindred, with 22 patients undergoing thyroidectomy after appropriate preoperative evaluation. A total of 9 patients had medullary thyroid cancer including 5 with a normal preoperative calcitonin level. A total of 11 patients had C-cell hyperplasia and 7 showed histological evidence of parathyroid disease. Only the index case had a phaeochromocytoma.

CONCLUSIONS

Genetic testing for germline mutations in the RET proto-oncogene has allowed precise identification of affected RET carriers and provided the opportunity for prophylactic or 'preclinical' surgery to treat and in fact to prevent medullary thyroid cancer. This concept of prophylactic surgery based on a genetic test is likely to be applied more widely as the tools of molecular biology advance.

Desmoplastic Stromal Reaction in Medullary Thyroid Cancer—An Intraoperative “Marker” for Lymph Node Metastases

BACKGROUND

Medullary thyroid cancer (MTC) disseminates early to lymph nodes (LN). There is no pre- or intraoperative marker to exclude LN involvement and thereby avoid lateral neck dissection in LN-negative patients.

MATERIALS AND METHODS

This study was intended to verify the observation that patients with MTC lacking desmoplastic stromal reaction (DSR) never have LN metastases. In 120 patients undergoing primary operation for sporadic MTC the prognostic value of DSR with respect to LN involvement was evaluated.

RESULTS

Thirty-two (27%) of 120 tumors were DSR negative, and 88 (73%) were DSR positive. All 32 (100%) DSR-negative tumors were LN negative (N0), and all patients were biochemically cured. Of 88 DSR-positive tumors, 57 (65%) were staged N0, and 31 (36%) were staged N1(LN positive; Fisher's exact test: P = 0.0001). In a comparison of the LN involvement to the DSR characteristics, 32 (36%) of the 89 N0 patients and none of the 31 N1 patients were DSR negative. The sensitivity of DSR in predicting N0 is 38% (95% confidence interval: CI 95% = 27 %-55%), the specificity is 100% (CI 95% = 88%-100%). The sensitivity and specificity for the parameter DSR to differentiate between N0 or N1 were 100% and 36%, respectively.

CONCLUSIONS

The desmoplastic stromal reaction appears to be an excellent intraoperative marker to predict LN involvement with a high specificity but low sensitivity. We therefore propose to avoid initial lateral neck dissection in MTC patients without DSR.