rationale for near total thyroidectomy in patients with multinodular ...

OriginalArticleRATIONALE FOR NEAR TOTAL THYROIDECTOMY INPATIENTS WITH MULTINODULAR GOITREM. NASEEM BALOCH, TABINDA ASLAM, MUMTAZ MAHERDepartment of General Surgery, Ward-2, Jinnah Postgraduate Medical Centre, KarachiABSTRACTObjective: To prove that Near total Thyroidectomy (NTT) with minimal residual tissue is the procedure of choice inpatients with Multi-Nodular Goitre (MNG).Design & Duration: Retrospective study from February 2002 to December 2006.Setting: Surgical Ward-II, Jinnah Postgraduate Medical Centre (JPMC), Karachi.Patients: A total of 521 consecutive patients, operated for simple or toxic MNG were included in this study.Methodology: Apart from detailed clinical work-up, investigations including thyroid function tests and thyroid scanswere carried out in all cases. All patients underwent near total thyroidectomy with preservation of recurrent laryngealnerves and parathyroid glands.Results: Out of 521 cases, 73(14%) had carcinoma on histopathological examination of the removed glands; 47(64%)underwent completion thyroidectomy which was uneventful, while 22 had radioiodine ablation with decreased dosagefor provision of minimal residual tissue and four declined further treatment.Conclusion: Near total thyroidectomy is a versatile surgical procedure for patients with MNG, keeping in view therisk of associated occult malignancy. Furthermore, the risk of damage to recurrent laryngeal nerve (RLN) andparathyroids is low in patients undergoing completion thyroidectomy. Hence, a more radical procedure should beadopted for surgical treatment in MNG.KEY WORDS: Near Total Thyroidectomy, Multinodular Goitre, Thyroid CarcinomaINTRODUCTIONThyroid Carcinoma (TC) is a relatively rare tumor, butit represents the most frequent form of cancer of endocrineglands. It represents 1% of human neoplasia andits annual incidence ranges from 0.5% to 10% in theworld population 1 , the figures increasing if cases ofoccult carcinoma are taken into consideration. Thisoccult carcinoma is a non-evident neoplasm, occuringwith cervical node disease or accidentally detected ina thyroid that has been removed for another pathologyor during an autopsy 2 . Epidemiologically ascertainedrisk factors are ionizing radiations, the presence of thy-Correspondence:Dr. Naseem Baloch, Senior Registrar Surgery,Dept. of Surgery, Ward-2, Jinnah PostgraduateMedical Centre, Karachi.Phones: 0333-2132461.roid adenoma and MNG of a long duration 1 . In literaturethe incidence of carcinoma in MNG varies from 7% to17% 3-8 . Further more, it seems that there is no statisticallysignificant difference between the incidence of TCin patients with a solitary nodule and those with MNG 6,9 .Thus multinodularity does not seem to be a certain indicativefactor of benign disease.Near total thyroidectomy involves total lobectomy onone side and sub-total lobectomy on the other side. Theresidual thyroid tissue is minimal and considering therisk of malignancy, future completion thyroidectomyis easier with risk of damage to RLN and parathyroidson one side only. Other treatment options like radioiodineablation would also be more effective in such patientsdue to less bulk of tumor, decreased amount ofdose required and less toxicity.PATIENTS & METHODSFrom Feb. 2002 to Dec. 2006, 521 consecutive patientswith a diagnosis of MNG were admitted in Ward-2,177Volume 23, Issue 3, 2007

Rationale for Near Total ThyroidectomyJPMC. Clinical workup and investigations includingthyroid function tests and thyroid scans were carriedout in all these cases; 502 patients were euthyroid whilethe remaining 19 had mildly increased T 4levels, andwere stabilized. Of the presenting symptoms, swellingin front of the neck was the chief complaint in all thecases followed by symptoms of hyperthyroidism, painand difficulty in swallowing.All the patients underwent near total thyroidectomy,with preservation of the recurrent laryngeal nerves andparathyroid glands. The maximum post-operative hospitalstay was 48 hours and no post-operative complicationwas recorded. Histopathology of the excised specimenwas received in 20 days, and further management inthe form of either completion thyroidectomy or radioiodineablation was carried out within a month, after aninformed and written consent from patient.RESULTSOf the 521 patients who underwent Near total Thyroidectomy,73 (14%) were found to have a carcinoma on histopathologicalexamination of the removed glands. Itwas papillary carcinoma in 60 cases, follicular in eightand undifferentiated carcinoma in five cases.Out of the 73 patients, 47 (64%) underwent completionthyroidectomy. In these patients, dissection was carriedout on one side only and there was no single case ofdamage to RLN or parathyroid glands. Vocal cords mobilitywas checked during extubation. Post-operativehospital stay was 48 hours on an average in these cases,three days being the maximum. These patients werefollowed in the Outpatient Dept. and their serum calciumlevels post-operatively were in the range of 8-10 mg/dl.Twenty two patients, out of the 73, went for radioiodineablation, which was given in a low dose due to the smallbulk of the residual thyroid tissue; consequently littletoxicity, if any, occurred. The remaining four patientsrefused any further treatment.DISCUSSIONTraditionally patients with MNG have been consideredless at risk of malignancy than those with single nodule.However, published reports show that the incidence ofmalignant tumors in patients with single nodule doesnot differ much from those with MNG 6,9 . MNG is arisk factor for epidemiologically ascertained TC 1 . Infact,the induction of TC following a diet lacking in Iodinewas demonstrated in mice and a confirmation is givenby the reduction of the mortality rate for TC registeredin Switzerland following the supplement of iodine inM. N. Baloch, T. Aslam, M. Maherthe table salt 10 . Epidemiological studies have demonstratedthat the incidence of carcinoma in patients withMNG is higher than that of the incidence in the generalpopulation 11,12 .In our retrospective analysis of 521 patients operatedfor MNG, 14% were found to have a carcinoma on definitivehistopathological examination. This incidence isnot significantly different from the risk of malignancyin solitary nodules 6,9 . Adoption of a more radical procedurein solitary nodule is justified by the risk of malignancyin it. Our study showed no significant differencein this risk in MNG. Hence a more radical procedure isjustified in MNG as well.Damage to the RLN is the most feared complicationwhile operating on the thyroid gland. Its complicationmay vary from simple neuropraxia to death. Conservinga nerve is more likely when operating on a gland thathas not been previously explored.Adoption of a radical procedure in the first instance letsthe surgeon identify and preserve the nerve on bothsides so that when a completion thyroidectomy is to betaken, only one side will need to be explored. Even ifan inadvertent damage occurs to the nerve, that will beunilateral only. Same is the case with parathyroids andtheir preservation can prevent the need of life long calciumreplacement in patients.CONCLUSIONThe risk of malignancy in MNG should not be underestimated, and the dominant nodule in MNG should beregarded as a solitary nodule in an otherwise normalgland so that a more radical procedure could be adopted.Our results suggest that near total thyroidectomy withminimal residual tissue is a versatile surgical procedurefor patients with multinodular goitre with low risk ofcomplications.REFERENCES1. Franceschi S. Epidemiologia del Carcinoma dellaTiroide. In: Miani P, ed. Carcinoma della Tiroide.Pisa: Pacini Editore; 1992. p.13-29.2. Miani P, Piemonte M, Bacchi G, Miani C. Fattoriprognostici e risultati terapeutici nel Carcinomadella Tiroide. In: Miani P, ed. Carcinoma della Tiroide.Pisa: Pacini Editore; 1992. p.167-97.3. Cole WH. Incidence of Carcinoma of the Thyroidgland in nodular goiter. Semin Surg Oncol 1991;7(2): 61-3.178Volume 23, Issue 3, 2007

Rationale for Near Total Thyroidectomy4. Koh KB, Chang KW. Carcinoma in MultinodularGoitre. Br J Surg 1992; 79(3): 266-7.5. Mathai V, Idikula J, Fenn S, Nair A. Do long-standingNodular Goitres result in malignancies? AustNZ J Surg 1994; 64: 180-2.6. McCall A, Jarosz H, Lawrence AM, Paloyan E.The incidence of Thyroid Carcinoma in solitarycold nodules and in Multinodular Goiters. Surgery1986; 100(6): 1128-32.7. Pelizzo MR, Toniato A, Piotto A, Bernante P. Cancerin Multinodular Goiter. Ann Ital Chir 1996; 67 (3):351-6.8. Sachmechi I, Miller E, Varatharajah R, et al. ThyroidM. N. Baloch, T. Aslam, M. MaherCarcinoma in single cold nodules and in cold nodulesof Multinodular Goiters. Endocr Pract 2000; 6 (1):110-2.9. Hossein G. Changing concepts in the diagnosis andmanagement of the thyroid nodules. EndocrinolMetabolism Clin N Am 1997; 26(4): 777-800.10. Franceschi S, Talamini R, Frassina A, Bidoli E.Diet and epithelial cancer of the Thyroid gland.Tumori 1990; 76: 331-8.11. Francis SG. The problem of nodular Goitre. MedClin N Am 1991; 75: 195-209.12. Clark OH, Quan-Yang D. Thyroid Cancer. MedClin N Am 1991; 75: 211-34.179Volume 23, Issue 3, 2007